(/
SLASH PINE
A
AT A
UBURN
CASE HISTORY
FORESTRY
DEPARTMENTAL SERIES NO.
JUNE 1964
AGRICULTURAL EXPERIMENT STATION
AUBURN
E. V. SMITH, Director
UNIVERSITY
AUBURN, ALABAMA

SLASH PINE AT AUBURN
A CASE HISTORY
FORESTRY
DEPARTMENTAL SERIES NO. i
JUNE 19614
FOR HE GRIULTRALEXPERIMENT 
STATION
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ADARS 
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A U 
B U 
R N 
U N 
I V 
E R 
S I T 
Y
CONTENTS
Page
O B JE C T IV E S -- - - - - - - - - - - - - - - -- - - - - - - - -
- - - - - - - - - - - - - -
DESCRIPTION OF PLANTING SITE AND
ITS RELATION TO NATURAL RANGE--4
CULTURAL OPERATIONS--- ----------- ------- ---- - 6
STAND DEVELOPMENT AND GROWTH OF PLANTATIONS ----------------- 8
YIELDS OF SLASH PINE SPACING PLANTATIONS ------------------------17
OTHER PLANTINGS -__________19
SUMMARY AND GENERAL OBSERVATIONS -----------------------------24
LITERATU RE C ITED ---------------------------------------------- 25
A P P E N D IX A -- - - - - - - - - - - - - - - - - - - - - - - - - - - - -- - - - - - - - - - - - - - - - - - - -2 6
A P P E N D IX B - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -4 1
FIRST PRINTING 2M
SLASH PINE AT AUBURN
A CASE HISTORY
KNOX W. LIVINGSTON
Assistant Professor
AT PRESENT and when plantations here described
were established, slash pine was one of four southern pines
of most commercial importance. Since the beginning of
the pine timber industry in the South, the importance of
slash pine relative to other species has gradually increased,
both as the supply of slash pine increased and as stands
of virgin longleaf pine were depleted.
Lumber from slash pine, in common with the other
three species, is marketed as southern yellow pine. 
If it
meets certain requirements for number of rings per inch
and per cent summerwood it may be classed as longleaf
yellow pine, a designation allowed only slash and long-
leaf pines by the lumber industry. It is used in all 
types
of construction, and the dense lumber is especially 
valu-
able in heavy construction where strength is an important
factor. Southern yellow pine is used extensively 
for pack-
aging, railway ties, poles, piling, and mine timbers. 
A
major use of continually increasing importance is for pulp
and paper products. The gum naval stores industry 
in
North America is dependent entirely on slash and longleaf
pines. Of all North American pines, slash pine 
has wood
of the highest average density and the highest average 
val-
ues of practically all strength characteristics (14).
Slash pine (Pinus elliottii Engelm. var. elliottii) is 
de-
scribed (6), as a large tree, about 50-100 ft. tall and 
24-40
inches in diameter, with erect straight axis and 
narrow
pointed crown. In the original forests it grew mainly in
depressions and on low sites with an abundance of 
mois-
ture in the surface layers, while longleaf pine occupied
higher ground in the same general area (5).
The natural geographic range of slash pine 
extends
north and east to the Santee River in coastal 
South Caro-
lina, south to Lake Okeechobee in Florida, 
and west to
the Mississippi River in coastal Louisiana (6). The 
natural
altitudinal range is mostly from sea level to less 
than 800
feet (5). Like loblolly pine, slash pine is an 
aggressive
species that quickly takes over abandoned fields 
(5). With
the exclusion of fire, slash pine often invades longleaf 
pine
land on ridges and slopes (2).
OBJECTIVES
Slash pine was first planted at Auburn, outside its nat-
ural range, as a means of testing the adaptability of a
species of recognized economic importance and with de-
sirable characteristics. Because of the early apparent suc-
cess of the first planting, more extensive plantings were
made to test the effects on growth and yield of different
original planting spacings and different thinning practices
and to compare slash pine with the native pines. Other,
more limited plantings of the several species were made
to test effects of burning (3), topographic situation, hard-
wood competition (11), competition between different
species of planted pines, and cultivation with fertilization
(4).
There were no specific forest management objectives in
terms of products or markets. The idea was to grow wood
and to seek favorable markets at the appropriate time.
Dates of Planting and Persons Responsible
The first field plantings were made in early 1927 under
the direction of L. M. Ware and the late Otto Brown.
1
Locally grown, 1-year old seedlings were used. The bulk
of the planting at Auburn was done from 1982 to 1984,
under Ware's direction. It was not until 1985 that a pro-
fessional forester was hired by the Agricultural Experi-
1 Professor Ware was then and is now Head of the Depart-
ment of Horticulture, Auburn University, then the Alabama
Polytechnic Institute. His department became the Depart-
ment of Horticulture and Forestry in 1928, retaining that title
until a separate Department of Forestry was established in
1947. It is largely the result of efforts by Mr. Ware that a De-
partment of Forestry exists at Auburn. Mr. Brown was forester
for the Cooperative Extension Service of the Alabama Poly-
technic Institute. Later he worked for several years with the
USDA Soil Conservation Service, returned to Alabama to join
the Agricultural Experiment Station, and recently, 1959, re-
tired as Superintendent of the Gulf Coast Substation. That
neither Mr. Ware nor Mr. Brown was a professionally trained
forester makes especially remarkable and commendable their
foresight and their contribution in initiating forestry research
in Alabama.
ment Station. He was the late D. J. Weddell,
2 
who super-
vised the plantations until he resigned in 1939. Other for-
esterers who have planned and supervised work in the
plantations include R. Stahelin, J. E. Bryan, Jr., W. R.
Bogess, G. I. Garin, and the writer.
Design
The design of the experiment was not as extensive as
might be used today. When the Auburn Plantations were
established, statistical methods and design were not used
as extensively as presently in agriculture and forestry.
3
Furthermore, plots had to be fitted into limited space.
Establishment was accomplished with extremely limited
funds. The allotment to initiate forestry research at Au-
burn was $80. Finally, in relation to the limited knowl-
edge of pine silviculture of the time, meeting the original
objectives did not require an elaborate design.
Because the original design of the Auburn plantations
did not, and could not conform with modern, accepted ex-
perimental design, this publication should be accepted
more as a historical account than as a research report. De-
tailed data are presented in order that the reader who
wishes can make his own comparisons. Readers are cau-
tioned against assuming that results will be duplicated
under different conditions.
DESCRIPTION OF PLANTING SITE AND
ITS RELATION TO NATURAL RANGE
The locality of the Auburn Plantations is about 75 or
100 miles north of the natural range of slash pine in the
Gulf Coastal Plain.
4 
It is a little more than 100 miles west
of the farthest inland range of the species, in the Atlantic
Coastal Plain of Georgia, and about 40 or 50 miles south
of the latitude of the northernmost extent, in coastal
South Carolina.
The climate at Auburn (13) is not much different
from that at most of the weather stations within the
natural range of slash pine. Averages and extremes of
temperature are within the range of those recorded at the
other stations. The average growing season of 237 days
at Auburn, however, is shorter than at most stations. Av-
erage annual precipitation at Auburn, 52.7 inches, is
higher than that in much of the natural slash pine belt.
Average warm season
5 
precipitation, however, is only 23.5
inches, which is 21/2 or more inches less than that at sta-
tions in the slash pine area.
The Auburn plantation area is one of transition from
Piedmont to Upper Coastal Plain. Topography is gently
rolling. Elevation is about 700 feet above sea level, more
than double the highest elevation of reported natural oc-
2 Mr. Weddell became State Forester of Georgia, then Dean
of the School of Forestry, University of Georgia. He remained
8 The first edition of R. A. Fisher's classic text, Statistical
Methods for Research Workers, had not been published until
1925; and it was not until 1935 that his other well known text,.
The Design of Experiments, appeared in its first edition. Sta-
tistical Methods, by G. W. Snedecor, was first published in
1987.
This excepts the major river valleys. Along the Alabama
the latitude of Auburn. This point is a little more than 100
miles from Auburn in a west-southwesterly direction.
6 April through September.
currence of slash pine. Soils are sandy loams and loamy
sands of the Chesterfield and Norfolk series, Coastal 
Plain
in origin. They are underlain at depths of 11 to 6 or more
feet by residual clays or sandy clays of Piedmont origin.
Pines native to the area are loblolly, longleaf, and short-
leaf. Naturally occurring forest types are loblolly pine-
shortleaf pine, loblolly pine, and loblolly pine-hardwoods
(10).
All of the plantations were established on abandoned
fields that had been in field crops, probably cotton and
corn exclusively, until 1926. Between 1926 and 1982, ex-
perimental horticulture plots occupied the area not already
planted in trees. Under cultivation, the area had suffered
moderate to severe soil erosion. Severity of erosion was
highly variable from place to place. A complex pattern 
of
difficult to evaluate site differences over the area resulted
from varying original soil conditions and varying severity
of erosion.
Plot Layout
Original Design. The first pure slash pine planting was
made in 1927 on a single, 1-acre plot (see Block No. 4 on
map). It adjoins similar plantings of loblolly pine (Block
3) and shortleaf pine (Block 5). Also established in 1927
was a single-row mixture of slash, loblolly, shortleaf, and
longleaf pines on a long, narrow plot of about 1 acre
(Block 2). Most of the subsequent plantings were made on
1/4-acre plots. There are 80 of these in the main body of
slash pine plantings (Blocks 31, 32, and 35). To each plot
was assigned an original planting spacing, a spacing after
first thinning (if made) and a final spacing.
Modification of Design. Through the years from the
time the plantations were established, original plans were
modified from time to time. The 1-acre slash and loblolly
pine plots established in 1927 were divided into quarters
at the time of first thinning (see map). Two subplots of
each species were thinned more heavily than the other
two.
The thinning pattern envisioned for the 1/4-acre spac-
ing plots was not followed after the time of first thinning.
Not only were the somewhat arbitrarily planned thinning
spacings abandoned, but some plots originally designated
for no thinning at any time were thinned, and plots orig-
inally assigned only one thinning were thinned again.
Final Plot Arrangement. When the acre planted to slash
pine in 1927 was later subdivided to provide four thin-
ning plots (see map), the area of record was cut to ap-
proximately 0.8 acre in order to provide a buffer strip
around the outside boundary. Thereby, approximately
0.2 acre was provided for each thinning plot. The entire
area of record is an irregular quadilateral. Three of the
thinning plots are trapezoidal, the other triangular.
The planting of slash, loblolly, shortleaf, and longleaf
pines in single row mixture is on an approximately rec-
tangular plot 72 feet wide and about 620 feet long (see
map). No further subdivision was made except by topo-
graphic position.
Each of the 30 plots that make up the main body of
slash pine plantings
6 
has an area of -acre (see map). All
6 Usually described to visitors as the spacing plantations or
spacing plots.
[4]
This is a map of the experimental area.
are rectangular, with dimensions slightly varied to allow
best use of available land. Most plots are about 96 by 114
feet.
To the 30 slash pine spacing plots were assigned 8 dif-
ferent planting spacings, ranging from 4 x 4 feet to 19
x 19 feet. Different thinning practices later applied
brought the number of different spacing-thinning combi-
nations to 15. All possible combinations are not repre-
sented, and the number of plots assigned to each combi-
nation that is represented ranged from 1 to 4, Table 1.
Fourteen of the plots are in a group arranged in two
rows of seven plots each, all planted to slash pine (Block
31). Thirteen plots are in a single row, which is part of
a group of plots in three rows, one slash pine, one long-
leaf pine, and the other loblolly pine (Block 32). Adjacent
plots of different species were planted at the same spacing.
The remaining three slash pine plots are scattered within
a group planted mostly to longleaf pine (Block 35).
There are no isolation strips between adjoining plots.
where plots adjoin roads or fire lanes there are buffer
strips of trees, usually a single row, planted at appropri-
ate spacings.
Relation of Plot Layout to Soils and Topography. Orig-
inally, sites were classed roughly into two groups, 
good
and poor. It was stated by Ware et al (15) that different
spacings were fairly evenly divided between good 
and
poor sites, except for the 8' X 8' plots, of which 
three
fell on poor sites and only one on a good site. 
This state-
ment is in most part upheld by site index estimates 
made
from height measurements when the plantations 
had
reached the age of 31 years. The only serious 
exceptions
are that both of the two 6' X 8' plots are 
on poor sites
and all 12' X 12' and wider spaced plots are on 
better
than average sites. Estimates of site index (index 
age 50)
range from 77 to 102 and average 87.6.
The plot with site index 102, a 6' X 6' plot 
that has
never been thinned, is exceptional in its situation. 
It is in
a low-lying area with excellent soil moisture 
conditions.
Trees planted on this plot were subjected to severe 
com-
petition from vines, briars, and brush. Because 
it is ex-
ceptional, this plot has been given the special designation,
6' X 6' E, and will be considered apart from other plots
of the same spacing.
TABLE 1. NUMBER OF SLASH PINE PLOTS REPRESENTING EACH SPACING-THINNING COMBINATION
Spacings
Thinnings (in feet)
4X4 6X6 6X8 8X8 91/
2
X91/
2 
12X12 16X16 19X19 All
No. No. No. No. No. No. No. No. No.
None
One commercial
One pre-commercial and 1 commercial
Two commercial, first light
Two commercial, first heavy
All
3 2 2 2
1 4
12
- 4 1 1 .. .- - 6
3 1 . . ---.. -- 4
6 11 2 4 2 2 2 1 80
[5]
I II
31-A-7 31A-6 
31-A-5 31-A-4 
31-A-3 31-A-2 
31 -- IAl
19xl9 16xl6 6x16 8x8 4x4 12xl2 6x6E"
r I
II
II II 
II
I
32C13 32-C12 32C- I32C10 32C-9 32C8 32-C-7 32-C6
1 
32-C5 32C4 32-C3 32-C2 32C-1
6x6 16x16 12x12 9v2x912 8x8 8x8 6x6 4x4 4x4 4x4 
6x6 6x6 6x6
1 111
700 900o 100 300 500
Sco in Feet
Establishment
Seed Source. With one exception, geographic source of
seed for the Auburn plantations is not definitely known.
Slash pine seed sown at Auburn in 1926 for the 1927
plantings were procured from a dealer in Pennsylvania.?
They may have come from anywhere in the slash pine
belt. Shortleaf pine seed for the same plantings were do-
nated by Page S. Bunker, then Alabama State Forester;
and loblolly pine seed were collected locally by Extension
Forester Brown. The longleaf pine seedlings planted in
1927 were donated by the Great Southern Lumber Com-
pany, Bogalusa, Louisiana.
The spacing plantations were established with seedlings
furnished by the Louisiana Department of Conservation.
It is likely that the seed were collected near the western
limit of slash pine's natural range.
Nursery Practice. Seedlings for the 1927 plantings (ex-
cept longleaf pine) were grown at the Agricultural Ex-
periment Station in nursery beds prepared in an area with
a heavy grass sod. After the sod was broken, most of
the roots were raked out. The 4-foot wide beds were
bordered with planks, then about 4 inches of leaf mold
and topsoil were placed in the beds and leveled. The
beds were treated with 0.6 per cent formaldehyde solu-
tion at a rate of 22 ounces per square foot, then watered
to carry the solution down through the leaf mold and top-
soil.
8 
The treatment was apparently ineffective, as there
was no odor of formaldehyde the next day and active
grubs were present.
In March 1926 seed were sown by hand in 1-inch deep
furrows and covered with sand, which had been heated to
a temperature thought sufficient to kill harmful fungi.
There was practically no damping-off when seed germi-
nated, but investigators carrying out the work did 
not at-
tribute this to soil treatment. Seedbeds were kept cov-
ered with lath frames during germination period and grow-
ing season. The beds were watered from a nearby hydrant
during dry seasons.
Seedlings for all later plantings presumably were grown
under standard conditions in state nurseries.
Planting Practices. All field planting was done by hand.
One-year-old
9 
nursery grown seedlings were slit planted
by two-man crews using mattocks or planting bars. Spac-
ing within rows and between rows was carefully con-
trolled.
Initial Survival. Records of survival at the end of the
second growing season were kept for some plots in the
spacing plantations. There are no records of first year
survival that the writer considers reliable. Second year
survival on six slash pine plots planted at 4' x 4' aver-
aged 76 per cent, with a range from 57 to 98 per cent.
Second year survival on the only 6' x 6' plot for which it
was recorded was 96 per cent. On the two 6' X 8' plots,
second year survival was 91 and 94 per cent.
Conyers B. Fleu, Germantown.
8 Purpose of the treatment is not recorded. Fumigation with
formaldehyde was a common practice in horticultural seedbeds
for the control of injurious insects and other organisms.
' One probable exception. Longleaf pine seedlings received
from Bogalusa and planted in 1927 appeared to be two years
old.
The weighted average of second year survival on the
nine slash pine plots for which there is a record is 78 per
cent. This compares with 79 per cent for loblolly pine
and 51 per cent for longleaf pine plots with comparable
records.
Replanting. All plots were replanted at least once to
bring number of living trees and spacing back to the orig-
inal. By replanting is meant going to every individual
tree planting spot and planting new seedlings wherever
the originals were dead or missing. Most plots, including
all the slash pine spacing plots, were replanted one time,
after the second growing season.
It is now recognized (1) that seedlings planted even 1
year after a plantation is established are usually quickly
overtopped by their older neighbors. They may remain
alive for a number of years; but except where large open-
ings occur, they seldom contribute significantly to stand
development except in terms of number of trees.
CULTURAL OPERATIONS
Thinning
Time of Thinning. All thinning operations were con-
ducted between growing seasons. On the basis of planta-
tion age (and, hence, size of trees) thinnings in the spac-
ing plantings may be categorized as follows: 1. pre-com-
merial, made only in 4' X 4' plantings; 2. early com-
mercial, made in 6' X 6', 6' X 8', and 8' X 8' plantings;
and 3. later commercial, made in all of the plots that had
pre-commercial or early commercial thinnings, in repre-
sentative 4' X 4' and 6' X 6' plantings that had not been
thinned before, and in all plantings between and includ-
ing 6' X 8' and 16' x 16' spacings.
Age of the 4' X 4' plantings when they were thinned
pre-commercially was 8 years. Early commercial thin-
nings of the spacing plantations were made at age 12 in
the 6' X 6' plantings, age 14 in the 6' X 8' plantings, and
age 15 in the 8' X 8' planting. Only slash pine and lob-
lolly pine received pre-commercial or early commercial
thinnings. Later commercial thinnings of all spacing plan-
tations except the two 6' X 8' plots and one of the 6' X
6' plots (all slash pine) were made at age 19. None of the
three plots excepted had received an earlier thinning, and
their age at time of thinning was 18 
years.l
?
Commercial thinnings in the slash and loblolly pine
plantings established in 1927 were made at ages 17 and
25 years. The single row mixture of four pine species,
also established in 1927, was thinned when the planting
had reached the age of 18 and again at age 25. The short-
leaf pine planting established in 1927 had not been thinned
before the final measurement.
Methods and Degree of Thinning. All thinnings were
primarily low thinnings, with certain modifications. De-
fective trees, regardless of crown class, were removed if
they seriously competed with trees to be left. Some trees
of lower crown classes and a few recognized defective
trees were left, if they did not seriously compete with
other remaining trees and appeared vigorous enough to
maintain satisfactory growth. An attempt was made to
1o Because it was thinned at an age different from the others,
the 6' X 6' plot thinned at age 18 has been given the special
designation 6' X 6' 
D.
[6]
Sp 
r
5 r'
4,.
This Slosh pine, plantee at 4
pre-commercial thinning at age 8
33 ii A.t ? :
p~~~~ 't's . " Y ~
4 spacing, is pictured after
thinning' at age 1 9.
,. .,pacing, is shown after first
provxide1 pr iltit i . tt is rentsitlitt wxith somne diegie t f
toft th' tcrowt, org Frech e tii ng mett hd ('t itit isei vx
tht th hi n ift s it t catrrti e ou~. t er modtiil ogy or iit
ilGcru t hi nn 1ing tts u Fromall tet tiretly dxif nt approachi tt li
towardet tno'mseclaturei, thuu couldimI4 be te 'e iprovemxnt
n bo() the pit el x' xxci a ndt t ter comeria xl hp thin-t
eint , e gxxi t ree x ii tititl i w ts d e xt i i'lls ofi lnel li
oftre esi lfi tt afr tt iti or avetxg tpainlgo en~
LUg tes etntIc-ir ej cal titijiex iii's itt e dx't ige di ito
widex thx'eiutxaigt atomth rit'ix xlt6' X< 6' ~ito 6' aver'
atg , f 'X 8'tt 8 t rititetg liet aret)i (Ac1)tuaiy anx aerate
thi at w lx tthiille prc-comm1 e i alli .i t dted8 lxl t 11h'
pe titxcs lia t iltl ree t sm l to hiu-t vrt for loca i ui' se
product (fe wodad ecpss . vigs ihsml
tre si iewt iion oflo ti i ILL
grees eityn, pligtand t 6 I 6 cig i shond afte sec'
pltngs comrialt thinnings at ageu 190 Producs fro 
1
4acre
ara ha shwn s luefto and smal trees pcut intofiree
woodi~ (left foregroun ) istr ' includ hl lsed as mecanal yed
tlig tin ing Thi'ifii iitit ini't if tti'e tin h lesfti ationais
xII t i a e iIS (tilli'e sl tpea ailet tilte it iti dxt ittfl its
px ilritentatti itt bslarga emoivtIiid ill tiningwr in iine
with' ih ther itit tinings pltxx xFutiit r 22ti 4wer etct.
Ast~i t trci l stt , tix'la' wiertttgx caged befor ltr'
cI mm' citl thtii ttrn 51tit Ier 17de xThl e toex t of te tint
ryastoi choreth iheit remiitt itreex xxiii iii 11 iit
I idii iitg ttti t i tt r ill fpeai l txit ut an t he desiti x xitilit' iti
fvidtig cr Ieatil'i tt of larg opening t i t he I stand~ti's.
fxet'x'd raiex Iro 51t to I' I T' sluax hut tptitatei lox
Salvage Cuts
Timing and Degree. Trees badly diseased with south-
ern fusiform rust
12 
were cut in most of the spacing planta-
tions when they were 11 years old. Plot 6' X 6' D, the
one that was 18 years old at the time of later commercial
thinning, was 10 years old when the salvage cut was made.
The two 6' X 8' plots received no salvage cut, nor did
the four 4' x 4' plots that had been thinned pre-com-
mercially.
Number of cankered trees per acre removed in the sal-
vage cut ranged from 4 to 120 per acre. Trees cut repre-
sented from 3 to 18 per cent of the basal area on indi-
vidual slash pine plots.
Reasons. Salvage cuts were made merely as a feature
of plantation management. They had no experimental
purpose. The reason that salvage cuts were made on many
plots only a year before they were thinned commercially
in accord with the original plans is obscure. The pre-
commercially thinned 4' X 4' plots received no salvage
cut because most diseased trees already had been removed.
There is no recorded reason why the 6' X 8' plots re-
ceived no salvage cut.
STAND DEVELOPMENT AND GROWTH
OF PLANTATIONS
Number of Trees per Acre
Original Spacing and Survival before any Cultural
Treatment. From the limited records available
13 
there
appears to be no relationship between planting spacing
and survival of seedlings during the first 2 years after
planting. Because even at the closest spacing little if any
competition between seedlings could occur, any relation-
ship during this period would be unexpected. Survival
trends after the second year are clouded by the replanting.
It is evident (Figure 1) that mortality on most plots was
relatively heavy (average of 26 plots, 6 per cent) during
the third year. Undoubtedly, this resulted largely from
the death of a high proportion of the replanted seedlings
in their first year. The magnitude of this effect and its du-
ration cannot be determined from the available data.
During the 8-year period between the third year and
time of salvage cutting, survival on 6' x 6' and wider
plantings appears not to be associated with planting spac-
ing. However, it appears that spacing as close as 4' x 4'
did result in sufficient competition between planted trees
to reduce survival during this period. Mortality on 4' X 4'
plots was 16 per cent from age 3 to age 11, compared
with an average of 6 per cent on the 6' X 6' and wider
spaced plots.
The exceptional plot, 6' X 6' E, showed mortality of
12 per cent during the 3 to 11-year age period, Figure 1,
Curve 5E. As was stated in the section on design, this
plot occupies a low area, with excellent soil moisture con-
ditions and exceptionally high site index. From the be-
ginning it has supported a dense growth of vines, briars,
and brush. Mortality of planted trees during the third
year (first year after replanting) was 32 per cent, much
higher than on any other plot. Undoubtedly, the low rate
of survival on the exceptional plot was related to site con-
12 Caused by Cronartium fusiforme (Ph.) Hedge and Hunt.
'8 Initial Survival, p. 6.
FIGURE 1. This is the number of trees per acre before any
cultural treatment. Curves on the chart present the following:
curve 3, 4' X 4' 1 pre-commercial and 1 commercial thinning
(4 plots); 4, 4' X 4', average, more than one group; 5E,
6' X 6' E no thinning (1 plot); 9, 6' X 6', average, more than
one group; 12, 6' X 8', average; 15, 8' X 8', average; 16,
9V2' X 9V2', 1 commercial thinning (2 plots); 17, 12' X 12',
1 commercial thinning (2 plots); 18, 16' X 16', 1 commercial
thinning (2 plots); and 19, 19' X 19', no thinning (1 plot),
ditions rather than to original spacing or cultural treat-
ments.
Original Spacing and Survival Following Salvage Cut,
Early Thinning, or Both. There is little doubt that com-
petition between trees planted at 4' X 4' and not thinned
early was a factor affecting survival between age 11 and
19 years. In fact, survival during this period may be re-
lated to spacing across the entire spacing range from 4'
X 4' to 16' X 16'. There is a steady decline in age 11
to 19 mortality rate with increasing spacing:
4' X 4', 39 per cent, (2 plots, 37 and 41 per cent);
6' X 6', 17 per cent (2 plots, 14 and 21 per cent);
8' X 8', 9 per cent (3 plots, range 7 to 13 per cent);
91/2' X 91/', 5 per cent (2 plots, 2 and 8 per cent);
12' X 12', 3 per cent (2 plots, 0 and 8 per cent); and
16' X 16', 1 per cent (2 plots, 0 and 3 per cent).
A 5 per cent mortality is indicated for the one 19' X 19'
plot (Figure 2); but, with only 19 trees on the 4-acre plot
at the beginning of the period, the only possible rate
lower than 5 per cent would be zero. Combining the 19'
x 19' plot with the two 16' X 16' plots gives a mortality
rate of 2 per cent, which is based on a more substantial
number of trees.
[81
10 II 12 13 14 15 16 17 18 19 20
Age (years)
FIGURE 2. This is the number of trees per acre between time
of first cultural treatment and later commercial thinning, plots
not thinned early. Curves on the chart show the following:
curve 4, 4' X 4', average, more than one group; 5E, 6' X 6'
E, no thinning (1 plot); 6D, 6' X 6' D, 1 commercial thinning
(1 plot); 9, 6' X 6', average, more than one group; 13,
8' X 8', 1 commercial thinning (3 plots); 16, 9
1
2' X 92',
1 commercial thinning (2 plots); 17, 12' X 12', 1 commercial
thinning (2 plots); 18, 16' X 16', 1 commercial thinning (2
plots); and 19, 19' X 19', no thinning (1 plot).
The slope of curve 6D on Figure 2, which represents
the 6' X 6' plot tallied at different ages (6' X 6' D), ap-
pears somewhat out of line with the general trend. It is
more nearly like the slope of curves for the wider spac-
ings. There is no ready explanation for this erratic be-
havior.
Mortality on plot 6' X 6' E was 46 per cent during
the 8-year period from age 11 to 19 years. Since basal
area stocking throughout the period was lower on plot
6' x 6' E than on a number of the plots with higher sur-
vival rates, the excessively high mortality apparently was
caused by factors other than competition between planted
trees.
For plots thinned early, there appears to be little con-
sistent difference in mortality rate among different origi-
nal spacings during the period between thinnings, Figure
3. The only spacings represented are 4' X 4', 6' X 6',
6' X 8', and 8' x 8'. Because each spacing was thinned
at a different age, comparisons are difficult. Mortality rate
appears to be mostly in the same range as the 8' X 
8'
and 91/2' X 91/2' plots not thinned early, Figure 2.
[9]
8 9 0 II 12 13 14 15 16 17 18 19
Age (years)
FIGURE 3. Given here is number of trees per acre between
time of first cultural treatment and later commercial thinning,
plots thinned early. Curves on chart show the following: curve
3, 4' X 4', 1 pre-commercial and 1 commercial thinning (4
plots); 7, 6' X 6', 2 commercial thinnings, first light (4 plots);
8, 6' X 6', 2 commercial thinnings, first heavy (3 plots); 10,
6' X 8', 2 commercial thinnings, first light (1 plot); 11,
6' X 8', 2 commercial thinnings, first heavy (1 plot); and 14,
8' X 8', 2 commercial thinnings, first light (1 plot).
F70
E
z
400
13
200 "
I1
18
I I I
8 19 20 21 22 23 24 25
Age (years)
26 27 28 29 30 31
FIGURE 4. This chart presents the number of trees per acre
after time of late thinning on plots not thinned early. Curves
on the chart give the following: curve 1, 4' X 4', no thinning
(1 plot); 2, 4' X 4', 1 commercial thinning (1 plot); 5,
6' X 6', no thinning (1 plot); 5E, 6' X 6' E, no thinning (1
plot); 6, 6' X 6', 1 commercial thinning (1 plot); 6D, 6' X 6'
D, 1 commercial thinning (1 plot); 13, 8' X 8', 1 commercial
thinning (3 plots); 16, 9V' X 9%', 1 commercial thinning
(2 plots); 17, 12' X 12', 1 commercial thinning (2 plots); 18,
16' X 16', 1 commercial thinning (2 plots); and 19, 19' X 19',
no thinning (1 plot).
_
U l 1 I I I1 I1 I I I .I I I L
v
I
TABLE 2. NUMBER OF TREES PER ACRE AT DIFFERENT PLANTATION AGES, SLASH
Age, years
2 3 6 7 8 8 9 10 10 11 11
Ft.
4X4
4X4
4X4
4X4
4X4
6X6
6X6
6X6
6X6
6X6
6X6
6 X 6D
6X8
6X8
6X8
8X8
8X8
8X8
91/
2 
X 91
2
12 X 12
16X16
19X19
Plot 
Plant
space
Cultural operation
Pre-comm. thinning
None None None None eorm t None
Before After
No. No. No. No. No. No. No.
Thin
No.
0
1
2
0
1
2
2
0'
1'
2
2
1
1
2
1
1
1
0
1:
o:
2,584'
2,5802
2,540
2,620
2,586
1,1261
1,1402
1,160
1,120
1,107
1,143
832'
1,124
8261
844
808
2,6881
2,6882
2,688
2,688
2,688
1,2161
1,2162
1,216
1,216
1,216
1,216
1,216'
1,216'
8961
896
896
6721
672
672
480
288
168
120
2,4051
2,4182
2,340
2,496
2,398
1,0771
1,0942
1,140
1,048
1,049
1,103
808'
2,398 730
None
No.
688
1,072
7981
820
776
Salvage cutting
Cut Before After
No. No. No.
52
No.
6
2
1
1
4
9
2
1
1
4
3
1
1
2
1
1
4
3
1
2
2
2
1
-- 4
2,158
-
2
2,220
2,096
1,062'1
1,0742
1,128
1,020
1,043
1,079
7283
2,046'
2,108
1,984
9841
9762
1,008
944
969
1,010
6803
5671 525'
568 521
564 536
412 378
262 232
148 142
80 76
Continued1 Average, all plots of specified spacing (with exceptions noted).
2 Average, plots of specified spacing not thinned early.
SNot included in 
averages.
SAverage no longer appropriate, following 
different thinning treatments.
Original Spacing and Survival Following the Time of
Later Thinning. It is evident from curves 1 and 2 on Fig-
ure 4 that mortality on the 4' X 4' plots not thinned
early continued at high rates following time of later com-
mercial thinning. Proportional mortality on 6' X 6' and
wider spacings not thinned early remained fairly well in
line with preceding period except for an increased rate
on the 6' X 6' plot thinned at age 19 (curve 6), especially
during the first 5 years, and a decreased rate on the ex-
ceptional 6' X 6' plot (curve 5E).
The later thinning left plantings thinned twice with only
a small range in number of trees, Figure 5. No particular
pattern of survival differences among the various spacings
is evident.
Thinning and Survival in the 4' X 4' Plantings. It is
quite obvious that pre-commercial thinning in the 4' X 4'
plantings reduced subsequent mortality. The highest av-
erage periodic annual rate of mortality in the plantings
thinned at age 8 occurred during the 2 years immediately
following thinning. This rate, 1.2 per cent, compares with
an average rate of 2.7 per cent per year in the unthinned
4' x 4' plantings during a 4-year period including the
same ages (8 to 10 yrs. for thinned plots, 7 to 11 years for
plots not thinned). During the year following salvage
cutting, mortality in the plantings not thinned pre-com-
mercially averaged 1.4 per cent, Figures 1 and 2. This
may be compared with 0.4 per cent per year in the pre-
commercially thinned plantings during the eleventh and
twelfth years.
14 
The big difference occurred during the 12
to 19 year period, when mortality on the unthinned 4' X
4' plots was 89 per cent. This is almost 8 times as high
as the mortality on the thinned plots (5 per cent) during
the same period. From age 19 to 81 years, 86 per cent of
the trees on the unthinned 4' X 4' plot were lost, 49 per
cent died on the plot thinned first at age 19, and only 10
per cent died on the 4 plots thinned twice.
While severe early thinning obviously reduced mortality
in the 4' X 4' plantings, it appears that thinning in the
previously unthinned 19-year-old plot may have had the
opposite effect. Although a comparison between two single
plots cannot be conclusive, the difference, especially dur-
ing the first 5 years after the time of thinning, is substan-
tial. There was 48 per cent periodic mortality as against
21 per cent during the same period on the plot not thinned.
In absolute figures, 64 of 809 trees (256 of 1,236 per
acre) died on the unthinned plot, and 77 of 180 trees (308
of 720 per acre) on the thinned plot. There was a differ-
ence of only 1 tree (4 per acre) between the two plots im-
mediately before thinning.
Thinning and Survival in the 6' X 6' Plantings. Early
commercial thinning, both light and heavy, in the 6' X 6'
1 These comparisons for short intervals are presented to show
that during no subsequent comparable period of observation
was average mortality as high on the plots thinned pre-com-
mercially as on the other 4' X 4' plots. Records for exactly
equivalent periods between age 8 and 12 years are not avail-
able.
[ 10]
609'
609
608
430
266
160
104
574'1
572
580
420
264
156
92
PINE SPACING PLANTINGS
TABLE 2. (Cont'd.) NUMBER OF TREES PER ACRE AT DIFFERENT PLANTATION 
AGES, SLASH PINE SPACING PLANTINGS
Age, years
12 12 12 14 14 
14 15 15
Comm. th.
None
Before After
None
Cultural operatic
Commercial thinning
Before After Before After B
18 18 19 19 
19 24 31 Total
trees cut.,
salv. and
SComm. thinning None or thinnings
efore After Before 
After Before
No. No. No. No. No. No. No. No. No. No. 
No.
4 4 
4
1,9762
.. 2,052
1,900
673
-- 
9382
992
884
955 604 599
1,006 427 417
520'
9883
7641
804 636
724 456
519'
515
532
876
230
140
72
952 488
4 4
616 364
444 296
1
1,236
1
864
364.
524 412
72
No. No. No.
4 4 4
,238
980
,240 720 412
647 328 805
4 4 4
806- 4 4
.- 788
748 400 316
549 302 286
389 246 220
--- 272
--- 488
4
336
244
4 4 4
473 264 249
396 286 236
360 284 226
224 158 154
No
792
368
294
668
288
274
213
208
456
328
286
244
232
216
128
. No.
S 4
-4 4
112
632
1 1,987
4 4
4 4
120
424
1 672
3 791
48
3 516
4 4
420
3 416
256
300
160
96
140 110 108 100 36
.. 68 68 4
1 Average, all plots of specified spacing (with exceptions 
noted).
2 Average, plots of specified 
spacing not thinned 
early.
' Not included in averages.
SAverage no longer appropriate, following different thinning 
treatments.
plantings appeared to reduce mortality rates, but the evi-
dence is not conclusive. There was no difference in 
mor-
tality rate between light and heavy thinnings. During 
the
7-year period following thinning at age 12, average mor-
I i0i
4  
, o
14
200
C)
0L
E 400
z2
200
18 19 20 21 22 23 24 25 26 27 28 29 30 31
Age (years)
FIGURE 5. This is the number of trees per acre after time of
later commercial thinning on plots thinned early. Curves
on the chart give the following: curve 3, 4' X 4', 1 pre-com-
mercial and 1 commercial thinning (4 plots); 7, 6' X 6', 2
commercial thinnings, first light (4 plots); 8, 6' X 6', 2 com-
mercial thinnings, first heavy (3 plots); 10, 6' X 8', 2 com-
mercial thinnings, first light (1 plot); 11, 6' X 8', 2 commercial
thinnings, first heavy (1 plot); and 14, 8' X 8', 2 commercial
thinnings, first light (1 plot).
[11]
tality rates were 9 per cent on the 7 thinned plots and 17
per cent on the 2 plots not thinned early (6' X 6' E
omitted). Though the difference between 9 and 17 per
cent appears substantial, the ranges for individual plots
in the two groups overlap. Furthermore, the curve for
the plot not thinned early and tallied at different ages
from the others (curve 6D on Figure 2) has a slope that
indicates an even lower proportional mortality than the
average of the thinned plots (curves 7 and 8 on Figure 3).
During the first 5 years following the time of later com-
mercial thinning, average mortality on 6' X 6' plots that
had light and heavy early commercial thinnings was, re-
spectively, 5 and 11 per cent. Ranges of the two groups
overlap widely, and the overall range on the 7 plots is
from 1 to 15 per cent. Averages for the next 7 years were
4 and 3 per cent, with overall range of 0 to 9 per cent.
The one 6' X 6' plot never thinned (6' X 6' E not con-
sidered) had a 9 per cent periodic mortality for the first
5 years, near the average of the plots thinned twice, but
jumped to 15 per cent for the next 7 years. The plot
thinned first at age 18 showed no mortality 
over the 5
years, 6 per cent over the next 7 years. Considerably dif-
ferent was the plot thinned first at age 19, with a 21 per
cent mortality rate for the first period and 9 per cent for
the next. As on the 4' X 4' plots, more trees out of a
smaller total died immediately following thinning on the
plot first thinned at age 19 than on the plot never thinned.
Together, evidence from the 4' X 4' and 6' X 6' spac-
ings might be taken as an indication that delayed, drastic
2,0182
2,100
1,936
682
9751
9662
1,004
928
628"
5241
520
536
378
232
140
76
I I I I I II
S I I I, I
? -- - I II , --
L--
14
3
HEIGHT DIAMETER AT DIFFERENT PLANTATION AGES, SLASH PINE SPACING PLANTINGS
Plots Plant Thin.
space
Age, years
6 7 8 8 9 10 10 11 11 12 12 12
Cultural operation
Pre-comm.
None None 
thinning
Before After
None None
Salvage cutting
Cut Before After
Comm. thinning
None
Before After
Ft.
4X4
4X4
4X4
4X4
4X4
6X6
6X6
6X6
6X6
6X6
6X6
6 X 6D
6X8
6X8
8X8
8X8
8X8
91
2 
X 91
2
12 X 12
16X16
6 8
6 8
8 8
8 8
8 8
9%X %
12X 2
No. In. In. In. In. In. In. In. In. In. In.
-1 2.414
2 - 2.32 -..... -. 
3.12 3.12 3.62
0 2.83... 3.2 3.1 3.7
1 2.4... .. 3.1 3.0 3.6
2 - 2.4 2.7 3.4 4.3 .. .. 4.9
0
1
2
2
03
12
21
2
2
1
2
1 19 X19 0
1.8
2.31
2.2
2.4
2.9'1
2.92
3.1
2.7
2.7
3.1
2.9'
3.0
3.71
3.7
3.7
. 4.21
4.22
4.4
4.1
4.0
4.2
4.83
4.0 ..
No.
6
2
1
1
4
9
2
1
1
4
3
1
1
2
1
1
4
83
1
2
2
2
4.11
4.12
4.3
4.0
4.0
4.2
4.73
4.31 4.2'
4.1 4.0
4.6 4.6
5.2 5.2
5.8 5.8
6.1 6.1
4.3 4.2
1 Average, all plots of specified spacing (with exceptions 
noted).
2 Average, all plots of specified spacing not thinned early.
' Not included in average.
4 Average no longer appropriate, following different thinning treatments.
thinning in these heavily stocked plantations may have
hastened the death of some of the released trees.
Thinning and Survival in the 6' X 8' and 8' X 8' Plant-
ings. Mortality for the 4-year period between thinnings
was 3.1 per cent on the 6' X 8' plot first thinned lightly,
2.6 per cent on the plot first thinned heavily. Mortality
was 8 and 13 per cent, respectively, on the two plots dur-
ing the first 6 years following the second thinning, 3.3 and
2.4 per cent during the next 7 years.
Among the four 8' X 8' plots, the one thinned twice
had 4 per cent mortality during the 4 years between thin-
nings. The remaining 3 plots, thinned once, averaged 8
per cent mortality during the 
5
-year period ending at the
same time. The plot that had been thinned twice had no
mortality during the first 5 years following second thin-
ning. The 3 plots thinned only once had an average of 6
per cent mortality during the period, but one of the 3
had no mortality. During the last 7 years the plots
thinned once had 2.0 per cent mortality, the plot thinned
twice, 1.7 per cent.
For spacings wider than 8' X 8', there are no com-
parisons between thinning treatments to be made.
Tree Diameters
5
Original Spacing and d.b.h. at Age 7 Years. On all but
8 plots the earliest record of tree diameters is for age 7
"Average diameter was determined by calculating the di-
ameter of the tree of average basal area.
years. Diameters were recorded for age 6 on plot 6' X 6'
D, which is the one thinned at a different age from most
others, and on the two 6' X 8' plots. The age 6 averages
are 1.8 inches for 6' X 6' D and 2.3 inches for the 6' X 8'
plots. Age 7 averages for different spacings are:
4' X 4' , 2.4 inches (6 plots, range 2.2 to 2.5 inches);
6' X 6' , 2.9 inches (9 plots, range 2.1 to 3.4 inches);
8' X 8' , 2.6 inches (4 plots, range 2.4 to 3.0 inches);
91/2
' 
X 91', 3.0 inches (2 plots, 2.6 and 3.3 inches);
12' x 12', 3.6 inches (2 plots, 3.2 and 3.8 inches);
16' x 16', 3.4 inches (2 plots, 3.1 and 3.8 inches); and
19' x 19', 2.4 inches (1 plot).
There is little evidence that average diameter had been
materially affected by spacing as early as age 7. The
range of the 6' X 6' plots (6' X 6' E omitted) overlaps
the range of every other spacing, and it includes all the
averages except the 12' X 12'. On the 26 individual plots,
the coefficient of correlation between average diameter
and average growing space per tree alive at age 7 is .256.
An equal or greater coefficient could occur about 21 times
per 100 samples of this size where no correlation exists.
Original Spacing and d.b.h. at Age 11 and 12 Years.
By age 11 there had begun to appear some relationship
[12]
2.61
2.5
3.0
3.0
3.6
3.4
2.4
In. In.
4.71 - 4
4.6 4.9
4.8 5.6
4.72
4.8
4.5
5.43
5.0
4.8
5.4
5.8
6.9
7.2
5.8
Continued
vrlv ---- u -
TABLE 3. AVERAGE BREAST
TABLE 3 (Cont'd.) AVERAGE BREAST HEIGHT DIAMETER AT DIFFERENT PLANTATION AGES, SLASH PINE SPACING PLANTINGS
Age, years
14 14 14 15 15 18 18 19 19 19 24 31
Cultural operation
None None None or
Before After Before After Before After Before After Before
In. In. In. In. In. In. In.
4 4 4 4 4
4.0' 5.32 4 4
4.0 5.4 6.2 7.0
3.9 - - 5.1 5.5 6.9 8.2
5.4 6.3 6.9 7.9 8.9
4 4 4 4 4 4
5.42 -- - 6.31
5.5 6.4 
7.1 7.7
5.3 ---- 6.3 6.9 7.8 8.7
5.7 -..- 6.7 7.3 8.4 9.4
6.4 .... 7.6 7.9 9.1 10.4
6.7- .. . . _ 8.3 .9.7 11.6
4.73 - ---- ---- 5.5 5.9 -6.9 8.2
5.61 4 
4 4 
4 4
5.5 5.4 -6.4 6.6 ....- 7.8 
8.9
-_ 5.6 5.8 -_6.9 7.0.... 8.2 
9.5
5.71 4 4 4 4
5.5 --....... 6.6 
7.1 8.0 8.9
6.1 - 6.4 6.4 - ... 7.2 
7.9 9.2 10.2
6.6 
8.0 8.2 9.2 10.3
7.7 - - - 9.1 
9.0 10.4 11.8
8.3 ...._10.1 10.0 11.5 12.8
6.9 -- 9.4.. 
11.1 12.8
1 Average, all plots of specified spacing (with exceptions 
noted).
2 Average, plots of specified spacing not thinned 
early.
SNot included in average.
SAverage no longer appropriate, following different thinning treatments.
between spacing and diameter, Table 3.16 At age 12, a
definite pattern of increasing average diameter with wider
spacing had developed:
4' X 4' , 3.6 inches (2 plots not pre-c. th., 3.6 and 3.7
inches);
6' X 6' , 4.7 inches (9 plots, range 4.3 to 5.0 inches);
8' X 8' , 5.0 inches (4 plots, range 4.6 to 5.4 inches);
91/2' X 91/2', 5.8 inches (2 plots, 5.4 and 6.2 inches);
12' X 12', 6.9 inches (2 plots, 6.6 and 7.1 inches);
16' X 16', 7.2 inches (2 plots, 6.8 and 7.6 inches); and
19' X 19', 5.8 inches (1 plot).
Based on the data from 2217 individual plots, there is a
highly significant correlation between age 12 average di-
ameter before thinning and average growing space per
tree at age 7 (observed r - .679; r.
01 
= .537).
Original Spacing and d.b.h. after Age 12 Years. Sub-
sequent to age 12, differences in diameter between differ-
16 In most cases, salvage cutting resulted 
in an immediate
slight reduction in average diameter. The reason for this is a
generally recognized tendency for rapidly growing slash pines
to be more susceptible to fusiform rust than slower growing
trees in the same stand. Because additional rust cankered trees
were found and removed in the commercial thinnings, the same
explanation applies where the thinnings resulted in slight re-
duction or no immediate change in diameter. Otherwise, the
essentially low thinnings would invariably have resulted in im-
mediate increase in average d.b.h.
1m Not included 
are 6' X 6' 
E, 4 plots 
thinned pre-com-
mercially, and 3 plots not tallied at age 12.
ent spacings with similar thinning histories increased, in
most cases fairly steadily. By age 31 the overall range in
plot averages was from 7.0 inches on the 4' X 4' plot
never thinned to 13.0 inches on one of the two 16' X 16'
plots. However, there was not much spread among plots
thinned twice, Table 3.
The exceptional plot (6' X 6' E) had trees of larger
diameter than others of the same spacing at all ages of 12
years and more. This is commensurate with the high qual-
ity of the site occupied by the plot and with the relatively
low stocking due to high mortality. Only the 3 widest
spacings had trees of larger average diameter than did
6' X 6' E.
Thinning and d.b.h., 4' x 4' Plantings. There is little
doubt that pre-commercial thinning in the 4' X 4' plant-
ings resulted in increased average diameter. In the first
place, the average diameter of trees left after the age 8
thinning was 3.4 inches, 21 per cent greater than the stand
average before thinning. Secondly, mean annual increase
on thinned plots during the 4 years from age 8 to 12 was
44 per cent greater than the annual increase on unthinned
plots during the 5-year period ending at the same time.
At the beginning of this 5-year period (age 7), there was
only 0.1 inch difference between the averages of thinned
and unthinned plots. Plots not thinned pre-commercially
were not measured at age 8, so a comparison between
identical periods cannot be made. At the end of the pe-
[13]
riods the difference was 1.3 inches. During the 2-year
period from age 12 to 14, the average diameter increase
was 25 per cent greater on the thinned plots than on the
unthinned plots.
During the next 5 years, from age 14 to 19, there was
a reversal. Diameter increase on thinned 4' X 4' plots
was 44 per cent less than increase in the unthinned plots.
Nevertheless, during the entire period from first measure-
ment or thinning to age 19 annual diameter increase on
thinned plots was 5 per cent greater than the increase on
unthinned plots. The reversal during the 14 to 19 year
age period resulted from high mortality among small 
trees
on the unthinned plots rather than from any faster diam-
eter growth of trees on the unthinned plots.
During the 19 to 31 year age period, diameter increases
on the unthinned, once-thinned, and twice-thinned 4' X 4'
plots averaged 1.6, 2.7, and 2.0 inches, respectively. Here,
as on the unthinned plots during an earlier period, the
relatively large increase on the plot thinned only at age
19 was related to high mortality among the smallest trees.
Thinning and d.b.h., 6' X 6' Plantings. In the 6' X 6'
plantings (6' X 6' E omitted) diameters were progressively
larger with increased intensity of thinning at every meas-
urement interval after thinnings were begun, Table 3.
Light early commercial thinning resulted in an immedi-
ate average diameter increase of 0.3 inch; heavy early
commercial thinning, an increase of 0.8 inch. Periodic
increases from age 12 to 19 years were:
no early thinning , 1.6 inches (2 plots, 1.6 and 
1.8
in.);
light early thinning , 1.8 inches (4 plots, range 1.6 to
1.9 inches);
heavy early thinning, 2.0 inches (3 plots, each 2.0
inches).
Age 19 thinning resulted in immediate average increases
of 0.6 inch both on the plot not thinned before and on
the plots thinned lightly before. The increase averaged
0.3 inch in the plots thinned heavily before. Periodic
increases from age 19 to 31 were:
no thinning , 1.3 inches (1 plot);
one thinning, age 19 , 1.8 inches (1 plot);
2 thinnings, first light, 2.1 inches (4 plots, range 1.8
to 2.3 inches);
2 thinnings, first heavy, 2.5 inches (3 plots, range 2.3
to 2.7 inches).
Thinning and d.b.h., 6' X 8' and Wider Spacings.
There appears to be no substantially different effect on
diameter of the two intensities of early thinning in the 6'
X 8' plantings. Diameter comparisons between early
thinning and no early thinning in the 8' x 8' plantings
are not valid because of the large difference in site quality.
No thinning comparisons are applicable in the spacings
wider than 8' X 8'.
Tree Heights
Height and Spacing. It is recognized that height of
trees at a given age is related more closely to site quality
than to stand density. In the slash pine spacing plots there
is little evidence that either original spacing or number of
trees surviving the first few years had any appreciable ef-
feet on height growth.
18 
There was essentially no corre-
lation between average growing space per tree alive at age
7 and average height at age 11 (r - -. 022 for 2219 plots.
An equal or greater r could occur more than 90 times per
100 samples of this size where no correlation exists.) Av-
erage height of all trees at age 31 was 65 feet. The range
for individual plots was 56 to 80 feet. Heights at differ-
ent ages are given in Table 4.
Height and Thinning. The slight apparenit increase in
height associated with thinning in the closer spacings is a
direct result of removal of the smaller trees. It probably
does not represent any stimulation of height growth.
Basal Area
Original Spacing and Basal Area. Basal area is a func-
tion of number of trees and diameter.
20 
It follows that
trends in basal area per acre fall between the trends in
number of trees per acre and average diameter. It may
be recalled from previous sections that proportional mor-
tality tended to decrease and diameter to increase with in-
creasingly wide spacings. These trends tend to equalize
basal area for different spacings. Nevertheless, there are
substantial differences, Figures 6-9. The greatest propor-
tional differences appeared at the young ages, before spac-
ing had greatly affected mortality and diameter. At age
7 years the plot averages ranged from 3 square feet (the
19' X 19' plot) to 80 square feet (a 4' X 4' plot), almost
a 27-fold difference. At age 31 the extremes were 61
square feet (the 19' X 19' plot) and 217 square feet (6' X
6' never thinned) a less than 4-fold difference.
Although all spacings do not appear exactly in the ex-
pected places at all ages, the graphs show an obvious
trend of substantially greater basal areas with closer spac-
ings.
Thinning and Basal Area. A direct and immediate re-
sult of any thinning is reduction in basal area. In fact,
basal area reduction is a commonly used measure of thin-
ning intensity. Following are the basal area percentages
removed by thinnings in the slash pine spacing plantations.
4' X 4', one thinning: age 19, 34 per cent.
4' X 4', two thinnings: age 8, 54 per cent; age 19,
6' X 6', one thinning:
6' X 6', two thinnings:
6' X 6', two thinnings:
6' x 8', two thinnings:
6' X 8', two thinnings:
8' X 8', one thinning:
8' X 8', two thinnings:
40 per cent.
age 19, 36 per cent (6' X 6'
D - age 18, 40 per cent).
age 12, 27 per cent; age 19,
36 per cent.
age 12, 44 per cent; age 19
31 per cent.
age 14, 22 per cent; age 18,
36 per cent.
age 14, 33 per cent; age 18,
30 per cent.
age 19, 36 per cent.
age 15, 23 per cent; age 19,
28 per cent.
18 Height records are not accurate enough for comparisons
of periodic increases. Some plot averages are based on samples
instead of all trees.
19 The 4 plots thinned pre-commercially 
and 4 others not
tallied at these ages are not included.20 Basal 
area of 
a tree = 
0.005454 
(d.b.h. )2, 
basal area 
ex-
pressed in square feet and diameter at breast height in inches.
[14]
TABLE 4. AVERAGE TOTAL HEIGHT OF ALL TREES AT DIFFERENT AGES, SLASH PINE SPACING PLANTATIONS
Age, years
3 9 10 11 12 12 14 14 18 19 19 24 31
Plots Plant Thin.
space
No.
6
2
1
1
4
9
2
1
1
4
3
1
1
2
1
1
4
3
1
2
2
2
1
Ft.
4X4
4X4
4X4
4X4
6X6
6X6
6X6
6X6
6X6
6X6
6 X 6E
6X6D
6X8
6X8
8X8
8X8
8X8
91 X91
2
12 X 12
16 X16
19 X19
No.
2
0
1
2
2
0
1
2
2
03
13
21
2
2
1
2
1
1
1
0
Salv.
None None None cut,
after
Ft. Ft. Ft. Ft.
31
32
3
3
2
31
32
3
2
3
3
33
30
21
231
23
23
21
2
2
2
252
25
25
281
292
30
27
28
29
31
251
24
28
29
32
80
23
Cultural operation
Comm. Comm.
None thin., None thin.,
after after
Ft. Ft. Ft. Ft.
3832
33
32
332
34
32
36
Comm.
thin.,
after
Ft.
Comm.
None thin.,
after
Ft. Ft.
4 4
49
383
34
86
41'
39
45
44
45
43
37
33
85
34
30
39
40
44
47
41
54
57
49
52
48
54
55
4
48
57
53
57
55
47
None
None or
before
Ft. Ft.
4 4
4 4
53 60
52 60
60 68
4 4
4 4
56 65
52 56
57 67
63 70
65 80
49 57
4 4
52 60
50 58
4 4
53 62
61 69
59 68
64
65
60
76
74
71
1 Average, all plots of specified spacing (with exceptions noted).
2 Average, all plots of specified spacing not thinned early.
2 Not included in 
average.
4 Average no longer appropriate, following different 
thinning treatments.
age 19, 30 per cent.
age 19, 31 per cent.
age 19, 23 per cent.
Actual basal areas before and after thinning appear in
Table 5.
Basal area increment following thinning was, in most
cases, less rapid than increment on plots of the same spac-
ing not thinned. In the 4' x 4' plantings thinned pre-
commercially at age 8, basal area per acre increased at
an average rate of 10.7 square feet per acre per year for
the next 6 years. On plots not thinned pre-commercially,
the average is 12.3 square feet for the same period.
21 
Sim-
ilar differences in favor of the unthinned plots hold for all
possible subdivisions of the 6-year period following pre-
commercial thininning.
After age 14, there was a reversal. Basal area incre-
ment during the 14- to 19-year period was 3.2 square
feet per acre per year in the unthinned 4' X 4' plantings,
6.6 square feet in thehe thinned plantations. By age 19
21 Based on the assumption that 
the two groups of plots in-
creased at the same rate from age 7, when both groups had the
same average basal area, until age 8. Actual increase from age
7 to 14 years on the plots not thinned pre-commercially aver-
ages 13.7 square feet per acre per year, not including the 11
square feet per acre removed in the salvage cut on the un-
thinned plots. Inclusion of the salvaged basal area would
further increase the apparent difference between thinning treat-
ments.
there was a net balance in basal area growth of only 4
square feet per acre in favor of the plots not previously
thinned.
During the 5-year period immediately following com-
merical thinning at age 19, basal area on the plots thinned
pre-commercially increased at an average rate of 3.4
square feet per acre per year to a total of 102 square feet
per acre. On the plot never thinned basal area increased
from 197 to 208 square feet per acre, an annual rate of
2.2 square feet. The plot thinned for the first time at age
19, its basal area reduced from 176 to 117 square feet by
thinning, suffered a subsequent decrease to 106 square
feet at age 24, a periodic annual rate of 2.2 (negative).
This decrease reflects the high mortality that followed thin-
ning, possibly a result of drastic cutting in the heavily
over-stocked stand.
The 4' X 4' plantings thinned twice maintained the av-
erage annual increase of 3.4 square feet per acre for the
final 7-year period to attain a total basal area of 126 square
feet at age 31. The plot thinned once, its trees apparently
recovering vigor to utilize extra growing space, increased
in basal area at a periodic annual rate of 4.1 square feet,
while the plot never thinned increased at only 1.0 square
foot during the final 7 years. In the entire 12-year period
following thinning, the unthinned and once thinned plots
showed the same average increase, 1.5 square feet per
year, to attain basal areas respectively of 215 and 135
square feet per acre at age 31.
[15]
91/' X 91/', one thinning:
12' X 12', one thinning:
16' X 16', one thinning:
TABLE 5. BASAL AREA PER ACRE AT DIFFERENT PLANTATION AGES, SLASH PINE SPACING PLANTINGS
Age, years
6 7 8 8 9 10 10 11 11 12 12 12
Plots Plant Thin. 
Cultural operation
space Pre-comm. Salvage cutting Comm. 
thinning
None None thinning None None None
Before After Cut Before After 
Before After
Ft. No.
4X 4 1
4 4
4X4 0
4X4 1
4X4 2
6X6 __
6X 6X6
6X6 0
6X6 1
6X6 2
6X6 2
6X6E 0
3
6X6D 13
6X8 21
6X8 2
6X8 2
8X8 1
8X8 1
8X8 2
91/
2 
X9/
2  
1
12 X12 1
16X16 1
19X19 0
Square feet
- 741
742
70
79
74
491
- 502
58
- 42
- 44
57
363
20 --
241
23
24 -
- 211
- 19
-- 28
- 20
- 18
10
.- 3
96 44 70
4
1162 105 148
122 112 159
110 98 136
- 90
1001
1052
119
92
94
106
913
No.
6
2
1
1
4
9
2
1
1
4
3
1
1
2
1
1
4
3
1
2
2
2
1
- -.- 561
- 53
_- - 65
- 60
901
902
100
81
84
96
833
50'1
46
61
56
48 42 60
80 28 40
8 7 14
Continued1 Average, all plots of specified spacing (with exceptions noted).
2 Average, all plots of specified spacing 
not thinned early.
3 Not included 
in average.
4 Average no longer appropriate, following different thinning treatments.
During the 7-year period following early commercial
thinning in the 6' X 6' plantings, average annual basal
area increment was 7.1 square feet per acre on plots
thinned heavily (to about 400 trees per acre) and 8.3
square feet on plots thinned more lightly (to about 600
trees per acre). The increment was 8.6 square feet for the
same period on plots not thinned. Most of the difference
in rates occurred during the first 2 years after time of
thinning. Respectively, annual rates for heavy, light, and
no early thinning were 10.5, 13.5, and 16.0 for the first 2
years; 5.8, 6.2, and 5.6 for the next 5-year period, ending
at age 19.
From age 19 to 24 years, the most rapid basal area in-
crement in the 6' x 6' plantings was on the plot never
thinned. The average annual rate was 4.8 square feet per
acre. On the plot first thinned at age 19, its basal area
reduced from 160 to 103 square feet per acre by the thin-
ning, increment was negligible, leading to 105 square feet
per acre at age 24. Apparently recovering, this once
thinned plot increased at an annual rate of 1.9 square
feet during the final 7 years to 118 square feet per acre at
age 31. Meanwhile, the unthinned plot increased hardly
at all, from 216 square feet at age 24 to 217 square feet
at age 31. Rates of basal area increase from age 19 to 31
were 2.1 square feet per acre per year on the plot never
thinned and 1.2 square feet on the plot thinned once.
On the plots thinned twice, the early thinning light, av-
erage basal area per acre increased from 86 square feet
after the age 19 thinning to 133 square feet at age 31, an
annual rate of 3.9 square feet. On plots thinned twice,
the early thinning heavy, the increase was from 84 to 126
square feet, an annual rate of 3.5 square feet.
In the 6' X 8' spacing, basal area gain was more rapid
on the lightly thinned plot than on the heavily thinned
plot, both between thinnings and following the second
thinning. The average annual increment rates were 8.8
and 7.5 square feet per acre respectively between thin-
nings and 4.2 and 2.5 square feet during the 12-year pe-
riod following later thinning. At age 31, basal area stock-
ing was 142 square feet per acre on the plot first thinned
lightly and 113 square feet on the plot first thinned
heavily.
Since the 8' X 8' plots thinned only once were not
measured at age 15, when the other plot got an early
thinning, there is no direct comparison for the period be-
tween time of early and later thinning. Average annual
basal area increment from age 14 to 19 was 5.4 square
feet per acre on the plots not thinned early. It was 5.2
square feet per acre from age 15 to 19 on the plot that
had a light early thinning. During the 12-year period fol-
lowing later thinning, annual increment was 2.8 square
feet per acre on the once-thinned plots and 4.2 square feet
[16]
.. 52
591
60
58
1181
109 80
129 72
Squar....
...
1162
127
105
983
721
67
86
70
TABLE 5 (Cont'd.) BASAL AREA PER ACRE AT DIFFERENT PLANTATION AGES, SLASH PINE SPACING PLANTINGS
Age, years
14 14 14 15 15 18 18 19 19 19 24 31
Cultural operation
None Commercial thinning None Comm. thinning Noneo
Before After Before After Before After Before After Before
Square feet
156
138
114
1083
84
118 91
94
4
88
80
186'
197 1
_.._ 176
. 141
4 4
176'
192
. 160
138
122
136 __
170'
181
159
108
4
1482
163
133
107
93
1273
1173
911
86
108
90
74
52
19
35
4 4 4
-4 4 - 4
208
117 106
85 102
4 4
4 4
216
103 105
86 106
84 100
141
128
- 110
- 89
215
185
126
217
118
133
126
152
166
142
113
72 88 105
81 109 132
86 104 126
70 92 97
60 78 89
46 61
1 Average, all plots of specified spacing (with exceptions noted).
2 Average, plots of specified spacing not thinned early.
Not included in average.
Average no longer appropriate, following different thinning treatments.
on the twice-thinned plot, representing increases from 72
to 105 and 81 to 132 
square feet per acre.
22
YIELDS OF SLASH PINE SPACING
PLANTATIONS
Introduction
Volume yields, however measured, are affected by 
such
a variety of factors that direct comparisons between differ-
ent spacings and cultural treatments can be misleading.
Much of the irregularity is a result of differences in site
quality. Averages are presented, but the reader is cau-
tioned to accept them for what they are, part of a his-
torical summary of the Auburn Plantations. By no means
are they yield tables in the conventional sense.
Stand volumes presented were computed from volume
tables for second growth slash pine (12). Pulpwood
cut was actually scaled, in stacks. For the sake of
conformity with early records, pulpwood volumes include
trees in the 4-inch diameter class (d.b.h. 3.6 to 4.5
inches), even though they are not generally considered
merchantable. In no case does the 4-inch class add appre-
22 The fact that the twice-thinned plot had the highest basal
area left after later thinning in the four 8' X 8' plots was not
an intended result. It is probably associated with the relatively
low site quality of the once-thinned plots.
ciably to total pulpwood yield of a plot.
23 
Total yields
are volumes cut added to standing volume.
Pulpwood. The principal commercial product of young
pine plantations is pulpwood. For the slash pine spacing
plantations, yields are summarized in Table 6. Highest
total yield through age 31 was on the 6' X 6' plot not
thinned, 85 cords per acre including 4 cords removed in
the salvage cut. The pulpwood yield on plot 6' X 6' E,
which also was not thinned but occupied a high quality site
with trees subjected to exceptional competition, was 64
cords per acre. Second highest yield, 80 cords per acre,
was on the 4' x 4' plot not thinned. Lowest yield, 21
cords per acre, was on the 19' x 19' plot, which was not
thinned.
Among the plantings that were thinned once, there is
a fairly steady decline in total pulpwood yield from close
to wider spacing. Only the 8' x 8' plots are out of line,
and this might be explained by their lower than average
site quality. Direct comparisons between spacings in the
plantings thinned twice have little meaning, for the critical
early thinnings were made at different ages.
"Tabular volumes for the 4-inch class have allowances for
the fact that some trees in the class do not contain a merchan-
table stick of pulpwood. Strict adherance to a 4.0 inch min-
imum diameter limit for pulpwood sticks (5'3" long) stacked
for scaling provided a similar allowance in the volume cut.
[17]
113
112
124
102
78
1291
182
125
a)
a,
20
0I l
5 6 7 8 9 10 II 12 13 14 
15 16 17 18 19 20 21 22 23 
24 25 26 27 28 29 30 31 32
Age (years)
FIGURE 6. This chart gives the 
basal area per acre on (1 
plot); 5E, 6' X 6' E, no thinning 
(1 plot); and 19, 19' X 19',
plots never thinned. Curves 
on chart give the following: 
no thinning (1 plot).
curve 1, 4' X 4', no thinning (1 plot); 
5, 6' X 6', no thinning
In the 4' X 4' spacing, 
two thinnings gave the low-
est total yield, no thinning gave 
the highest. The 4' X 4'
plot thinned only at age 19 shows 
a relatively small incre-
ment immediately following 
thinning, possibly from shock
of the severe thinning.
Highest yield in the 6' X 
6' spacing also came with
no thinning. However, plots 
thinned twice gave a slightly
higher average yield than 
plots thinned only once. 
Plots
thinned once are on sites 
of lower quality, and the 
one
thinned at age 19 shows a 
relatively small increment fol-
lowing drastic thinning. However, 
the age 18 thinning in
the other plot (6' X 6' D) 
caused no such setback.
In the 6' X 8' spacing, 
light early thinning may 
have
resulted in a higher yield 
than heavy early thinning. 
The
difference in yield appears 
to be greater than should 
be
attributed to the small difference 
in site quality.
In the 8' X 8' spacing, 
the plot thinned twice 
gave the
highest yield. It is on 
a much better site than 
the 3 plots
thinned only once.
Sawtimber. Sawtimber volumes at 
time of the last 3
measurements are presented in Table 
7. Although a few
sawtimber size trees were 
cut in the later thinnings, 
no
sawtimber volume cut is shown. The amount 
was not suf-
ficient for a commercially operable sawtimber 
cut. There-
fore the material was scaled as 
pulpwood.
The volume tables used 
in the computation of sawlog
volumes include the 7-inch diameter 
class as their mini-
mum limit. Under most circumstances 
the 9-inch class
is more nearly the minimum merchantable 
size. Volumes
to both minima are presented. 
The scale in which volumes
are expressed is based on 
the International (1/4-inch 
kerf)
log rule, which closely approximates 
actual lumber out-
put attainable in a well run, properly 
adjusted sawmill.
Volumes are gross scale, 
that is, no deduction for defect
was made. The reader who 
wishes to make comparisons
on a different basis can derive 
volumes by other rules and
to other limits of merchantability 
from the stand tables
(Appendix B).
[18]
FIGURE 7. This chart gives the basal area per acre on thinning (1 plot); 13, 8' X 8', 1 commercial thinning (3 plots);
plots thinned once. Curves in the chart present the following: 16, 92' X 912', 1 commercial thinning (2 plots); 17,
curve, 2, 4' X 4', 1 commercial thinning (1 plot); 6, 6' X 6', 12' X 12', 1 commercial thinning (2 plots); and 18, 16' X 16',
1 commercial thinning (1 plot); 6D, 6' X 6' D, 1 commercial 1 commercial thinning (2 plots).
Sawtimber yields show relatively smaller variations be-
tween spacings than do pulpwood yields. This is to be
expected because sawtimber volume varies more with di-
ameter difference, and the generally greater diameters of
the wider spacings tend to compensate for the lower basal
areas.
Cubic Volume. Total cubic volume yields of stemwood
are summarized in Table 8. The trend is toward greater
volumes at closer spacings. It is probable that thinning
had no appreciable effect on total volume yields.
Other Plantings
Eroded Field Plantings. In Table 9 are presented pulp-
wood yields of the 1927 plantings, of locally grown seed-
lings, made on a severely eroded field. Planting spacing
was 6' X 6'. Slash pine gave the highest yield of the
three species planted. Growth of shortleaf pine was so
slow that no thinnings were made before the last meas-
urement.
With both slash and loblolly pine, increment between
thinnings was higher on plots that had light first thinnings
than on plots that had heavy first thinnings. There was a
reversal following the second thinning, and total yields are
not substantially different.
Planting of 4 Species in Single Row Mixture. The long,
narrow plot extends from near the top of a ridge to a
moist fiat, or well-drained bottom. Actually, the fiat is
roughly midway, both in distance and elevation, between
the ridge crest and a permanent stream. Planting rows
extend the length of the plot, and there are 3 repetitions
of the sequence, shortleaf pine, longleaf pine, slash pine,
and loblolly pine. Planting spacing is 6' X 6'. The plot
has had two commercial thinnings, at age 18 and 25 years.
The plot is subdivided into 4 topographic situations,
Table 10. The upper slope is a gently sloping area ad-
jacent to the loblolly pine eroded field planting. The mid-
dle slope has almost the same appearance, but presumably
has somewhat better soil conditions. The lower slope is
steeper and is very badly eroded. The bottom is almost
fiat.
On the upper slope, slash pine makes up most of the
dominant stand and has given the highest yield of the 4
species. On all other situations, loblolly pine has given
the highest yield. However, there is a complicating fac-
tor. Adjacent to the plot edge along the middle and lower
slopes is a woods trail that provides the outside row of
loblolly pine freedom from competition on one side. This
outside row accounts for more than its proportional share
of the volume. Slash pines are generally larger and taller
[19]
9)
a..
a)
U"
5 6 7 8 9 10 II 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
Age (years)
FIGURE 8. This chart gives the basal area per acre on
plots thinned twice, early thinning light commercial. Curves in
the chart present the following: curve 7, 6' X 6', 2 corn-
than loblolly pines of inside rows on all the slope situa-
tions. On the flat, however, loblolly pines of all rows are
usually larger.
As is to be expected because of its early growth char-
acteristics, longleaf pine made a negligible contribution
to yield from this mixed planting. There are only a few
longleaf pines still living. Shortleaf pine made a relatively
mercial thinnings, first light (4 plots); 10, 6' X< 8', 2 com-
mercial thinnings, first light (1 plot); and 14, 8' X 8', 2
commercial thinnings, first light (1 plot).
small, but more than negligible contribution to yield. Liv-
ing shortleaf pines are present in some number, but they
are small in relation to loblolly and slash. Highest relative
and absolute per acre yield of shortleaf pine was on the
upper slope, where one outside row had an advantage
similar to that of loblolly pine on the middle and lower
slopes.
TABLE 6. PULPWOOD VOLUME PER ACRE AT DIFFERENT AGES AND TOTAL 31-YEAR YIELD, SLASH PINE SPACING PLANTINGS
Age, years
9 10 11 12 12 14 14 15 15 18 18
Plots Plant Thin. 
Cultural operation
Salgcee Early commercial 
Early commercial Later 
commercial
None Salvage_______ thinning None thinning 
thinning
Cut Cut Cut Left Cut Cut Left Cut Left
No. Ft. No. Cords per acre
1 4X 4 0 ____ ____ 2.8 -- -- - - - --- -- - --
1 4 X 4 1 ---- ---- 3.2 ---- ---- ---- ---- ---- - -- - -
4 4X 4 2 - -- ----------- -- -
- --
1 6X 6 0 -- -- 4.0 --- -- - --- --- -- 
- ---
1 6X6 12.-- --- -
4 6X 6 2 _-__ -_ 2.7 3.0 12.1 _ _- - -__ __ -_
3 6X 6 2 __ 1.9 5.5 10.7 ___ -- _-____-__ ---
1 6 X 6E 0 - --- 2.0 ----- - - -------
1 6 X 6D 1 _- _ 0.4 _ _ _ 19.2 ___- _-_ - _- 11.8 17.1
1 6X8 2 6.3 -__ __-__ __ 6.3 -___ -_ 10.9 19.7
1 6X8 2 6.0 __ -_--_ 8.4 ___ -_-_ 6.2 14.6
3 8X 8 1 - - - 1.2 -- ---- -- - -- -- - -
1 8X8 2 ___ __ 2.0 _______ 5.2 17.4 ___ ---
2 91/
2
X 9/
2  
1 --- -- .8 --- ---- --- ----- 
-----
2 12 X 12 1 - -- 1.6 --- -- --- --- 
--- --- -- -
2 16X 16 1 -- ---- .3 -- ----- --- - ----
1 19 X 19 0 - - .4 -- - -- --- - -- -
---- - ---
Continued
[20]
FIGURE 9. This chart presents the basal area per acre on 3, 4' X 4', 
1 pre-commercial and 1 commercial thinning (4
plots thinned twice, early thinning pre-commercial or heavy 
plots); 8, 6' X 6', 2 commercial thinnings, first heavy (3 plots);
commercial. Curves in the chart present the following: curve 
and 11, 6' X 8', 2 commercial thinnings, first heavy (1 plot).
TABLE 6 (Cont'd.) PULPWOOD VOLUME PER ACRE AT DIFFERENT 
AGES AND TOTAL 3-YEAR YIELD, SLASH PINE SPACING 
PLANTINGS
Age, years
19 19 19 24 31 
Ratio,
19 19 
19 24 31 
Total Total Average 
total
Cultural operation 
volume 31-year site 
yield to
Commercial thinning harvested yield index normal
None Cut Left None None 
yield
1
Cords per acre
46.3 
61.2 77.3 2.8 80.1 
88 1.48
... 14.1 27.9 
30.7 47.1 17.3 
64.4 89 1.18
14.0 21.9 81.2 
45.3 14.0 59.8 
88 1.10
52.5.. 
64.8 81.2 4.0 85.2 
92 1.51
11.9 23.0 29.1 
37.1 14.3 51.4 -
80 1.04
12.8 23.2 31.6 
46.3 18.5 64.8 
87 1.21
9.6 21.4 31.4 45.3 
17.0 62.3 89 1.14
38.1 _47.9 
61.7 2.0 63.7 102 
1.04
_31.9 51.1 12.2 
63.3 79 1.31
_.._... 29.5 45.2 
17.2 62.4 80 1.27
...... 22.5 34.1 
14.6 48.7 77 1.04
9.5 16.9 24.1 35.1 
10.7 45.8 82 
.91
7.1 19.5 33.4 46.7 
14.3 61.0 88 1.13
-__9.8 22.0 81.0 
42.9 10.6 53.5 86 
1.01
8.5 18.5 29.4 86.0 
10.1 46.1 95 .80
.... 4.2 15.2 24.9 
32.5 4.5 87.0 94 
.65
7.8.. 18.0 
21.0 .4 21.4 90 
.39
SNormal yield from 
(USDA, 1929).
[21]
TABLE 7. SAWTIMBER VOLUME PER ACRE AND RECENT PERIODIC ANNUAL INCREMENT, SLASH PINE SPACING 
PLANTINGS
9 inch minimum d.b.h.
Plots
Plant
space
No. Ft.
1 4X4
1 4X4
4 4X4
1 6X6
1 6X6
4 6X6
3 6X6
1 6X6E
1 6X6D
1 6X8
1 6X8
3 8X8
1 8X8
2 12X 12
2 16X16
1 19X19
1'International 1/4 " Rule.
2 (USDA, 1929).
Thin.
No.
0
1
2
0
1
2
2
0
1
2
2
1
2
1
1
1
0
Volume after later Periodic
thinning (if made) 
annual
increment
Age 18 Age 19 (age 19-24)
Board f eet
1 
per acre
___250 676
___1,040 836
___740 706
___ 4,020 1,400
___1,960 844
___ 2,500 965
___ 3,030 1,053
___ 8,720 1,490
370 ___445
910 ___568
1,220 ___523
1,895 590
___ 3,210 1,158
___ 4,645 879
4,855 1,051
___ 4,800 983
___ 2,370 490
Periodic
Volume annual
at age 24 increment
(age 24-31)
3,630
5,220
4,270
11,020
6,180
7,325
8,295
16,170
3,040
4,320
4,360
4,845
9,000
9,040
10,110
9,715
4,820
1,526
1,249
1,129
1,231
659
988
1,140
1,333
1,200
1,084
949
809.
979
873
650
575
517
TABLE 8. TOTAL YIELD IN CUBIC FEET PER ACRE FOR TREES OF 4 INCH 
DIAMETER CLASS
PLANTATIONS AT 31 YEARS OF AGE
AND LARGER, SLASH PINE SPACING
Thinning Group
4X 4'
Cu. ft.
6'X6'
Cu. ft.
Planting spacing
6'X8' 8'X8' 91/
2
'X9/
2
'
Cu. ft. Cu. ft. Cu. ft.
12' X 12'
Cu. ft.
Cu.
No thinning 6,224 65,641 __ ____
One th., later comm. 5,010 4,1592 
_ 3,685 4,413 3,842 3p
Two th., 1st light comm. ____ ,394 
5,003 5,083
Two th., 1st heavy comm. 5,4813 4,002 
____
Two th., 1st pre-comm. 5,299_
1 6'X 6'E, with 5,279 cuhic feet, excluded. Average including 
6' X 6'E is 6,022.
2 6' X 6'D, with 5,076 cuhic feet, excluded. Average including 6' X 6'D is 4,618.
3 Includes a small, hut unknown, amount from trees smaller than 3.6 inches d.h.h. cut in the early thinning.
C16' 19' X19'
ft. Cu. ft.
_ 1,798
82
TABLE 9. PULPWOOD YIELD THROUGH 36 YEARS, PLANTINGS ON BADLY ERODED FIELD
1
Age 17
Species and thinning group
Slash pine, 1st thinned
to ahout 600 trees
per acre
Slash pine, 1st thinned
to ahout 400 trees
per acre
Lohlolly pine, 1st
thinned to ahout 600
trees per acre
Lohlolly pine, 1st
thinned to ahout 400
trees per acre
Shortleaf ine, never thinned
Area Cut
in 1st
thinning
Acres
0.196
.208
.404
.203
.202
.405
.202
.203
.405
.202
.203
.405
.932
6.12
6.49
6.31
8.97
10.64
9.80
2.97
1.23
2.10
7.18
4.19
5.68
Stand
after
thinning
18.37
12.50
15.35
13.30
11.88
12.59
11.88
17.24
14.57
10.40
19.21
14.81
Periodic_
annual
increment
age 17-25
1.18
1.41
1.30
.69
1.19
.94
1.20
1.40
1.30
.73
.72
.73
Age 25
Cut Stand
in 2nd after
thinning thinning
Cords per acre
10.55 17.24
7.85 15.95
9.16 16.58
5.28 13.53
7.24 14.18
6.20 13.86
6.84 14.67
11.38 17.08
9.11 15.87
4.61 11.62
6.46 18.52
5.54 15.08
___ 9.15
Periodic
annual Volume,
increment age 36
age 25-36
0.74
.65
.69
.71
.81
.76
.33
.03
.18
.32
.48
.40
.23
25.43
23.05
24.20
21.31
23.05
22.18
18.35
17.45
17.90
15.16
23.81
19.50
11.63
Volume
at age 31
14,310
13,960
12,175
19,640
10,790
14,240
16,275
25,500
11,440
11,910
11,000
10,510
15,850
15,150
14,660
13,740
8,440
Continued
Total
yield
in 36
years
42.10
37.39
39.672
35.56
40.93
38.242
28.16
30.06
29.112
26.95
34.46
30.722
11.63
2 The third row in each instance indicates the weighted average 
production of the two suhplots ahove.
[22]
TABLE 7 (Gont'd.) SAWTIMBER VOLUME PER ACRE AND REGENT PERIODIC ANNUAL INCREMENT, SLASH PINE SPACING PLANTINGS
7 inch minimum d.b.h.
Volume after later
thinning (if made) Periodic 
annual
Age 18 Age 
19 increment 
(age 19-24)
Volume at
age 24
Periodic annual
increment (age 24-31)
Board feet' per acre
___ 5,510
___ 3,740
____ 4,460
_ 10,120
___ 5,320
___ 5,050
S 5,855
___ 11,080
2,780 __
3,650
2,960
3,935
5,260
6,420
5,990
5,225
2,760
1 International 
1/4" Rule.
(USDA, 1929).
TABLE 10. PULPWOOD YIELD THROUGH 36 YEARS, 
PLANTING OF LOBLOLLY, LONGLEAF, SHORTLEAF, AND SLASH
PINES IN SINGLE Row MIXTURE'
Topographic Species
situation
Age 25 Periodic Periodic Total
Ara Site, annual 
Volume annual Volume, yield in
Ara index Cut in Stand after increment age 31 increment age 36 3 er
thinning thinning age 25-31 age 
31-36 3 er
Cords per acre
Upper Loblolly pine
slope Longleaf pine
( gentle) Shortleaf pine
Slash pine
All combined
Middle Loblolly pine
slope Longleaf pine
(gentle) Shortleaf pine
Slash pine
All combined
Lower Loblolly pine
s lope Longleaf pine
steep) Shortleaf pine
Slash pine
All combined
Well-drained Loblolly pine
bottom Longleaf pine
(practically Shortleaf pine
flat) Slash pine
All combined
All Loblolly pine
positions Longleaf pine
Shortleaf pine
Slash pine
All combined
0.082
.081
.082
.082
.327
.058
.058
.058
.059
.233
.031
.033
.034
.031
.129
.084
.084
.084
.085
.337
.255
.257
.258
.256
1.026
64 14.7
.0
57 3.4
64 8.3
_--6.6
70 14.3
---. 0
55 1.2
73 8.4
-_- 6.0
82 11.1
---. 0
---. 0
84 6.4
--- 4.2
88 22.1
---- .0
70 .7
86 11.4
-_-8.5
_-- 16.6
-- .0
-_-1.6
- 9.1
-- _6.8
12.7 1.63 22.5
.0 .07 .4
10.5 .68 14.6
28.4 3.35 48.5
12.9 1.43 21.5
38.5 3.88 61.8
.0 .00 .0
8.3 .58 11.8
35.1 2.98 53.0
20.6 1.85 31.7
54.7 4.35 80.8
.0 .00 .0
5.6 -. 35 3.5
30.2 1.63 40.0
21.8 1.33 29.8
70.0 8.07 118.4
.0 .03 .2
6.3 .28 8.0
28.4 2.42 42.9
26.2 2.70 42.4
42.6 4.60 70.2
.0 .03 .2
7.8 .42 10.3
30.2 2.73 46.6
20.1 1.93 31.7
Volume at
age 31
Normal yield
2
age 31
1,188
882
732
1,284
682
870
937
1,276
677
735
528
605
1,100
816
934
923
472
11,450
8,150
8,120
16,540
8,730
9,400
10,540
17,460
7,532
8,120
6,600
6,960
10,760
10,500
10,660
9,840
5,120
1,300
1,104
996
1,193
569
994
954
1,217
1,263
850
839
701
960
809
605
568
526
20,550
15,880
15,095
24,890
12,710
16,355
17,220
25,980
15,680
14,010
12,000
11,865
17,480
16,160
14,895
13,815
8,800
16,710
17,220-
16,710
18,730
12,580
16,190
17,220
23,710
12,110
12,580
11,170
13,610
16,710
15,670
20,230
19,730
17,740
-0.50
.02
.46
3.48
.88
1.60
.00
.04
3.10
1.20
1.98
.00
.02
-.60
.36
4.54
-. 02
.26
2.86
1.92
1.92
.00
.26
2.76
1.24
20.0
.5
16.9
65.9
25.9
69.8
.0
12.0
68.5
37.7
90.7
.0
3.6
37.0
31.6
141.1
.1
9.3
57.2
52.0
79.8
.2
11.6
60.4
37.9
34.7
.5
20.3
74.2
32.5
84.1
.0
13.2
76.9
43.7
101.8
.0
3.6
43.4
35.8
163.2
.1
10.0
68.6
60.5
96.4
.2
13.2
69.5
44.72
1'In addition, a light thinning at age 18 yielded 6.1 cords per acre. The distribution 
by topographic situation and species is
not known. It is believed that it was 
mostly loblolly pine that had been 
planted by mistake in the slash pine 
rows.
2 Including the age 18 thinning, average total yield is 50.8 cords per acre.
[23]
- L ~A ~ -,
l t
i,
e ;
The area at left was badly eroded before planting to Slosh pine in 1 927
second commercial thinning.
SUMMARY AND GENERAL OBSERVATIONS
ilaish pili(e on its t'hi te ilolutil s us eiu JM' i ( oft]ul
\iht a om ciltig i id e , was 192 ti firs t ' t itse i
t'2s in soes t pie iii th \tiatiithaiA'a. lc liiitt'ti a tiilit'eitt
lan i'td sl s sa f st ltipoI li tlit , t'itest' sjc~it' il I
Exep 4' otni toit suits. sat ine ougr\.alo t-ldu
loblsliysi nes its leit'asi og p tit r oe st i t pe' o of 4't t6
l (ast 36 uers.' IhiI9
Illitional pI lia tigis s ma u tin 1932 cof1m4 ata e suc-ii
leto slaishipt( 5 i e A ibeitt area. itli ite ealii t d Ifret
spac ing igs. ie ifeetclurltet ets hyd m
ith at t a rteth ttl ( u ther wsas it ltad inc114 ath
tnhu viat w 9111ptSit uisi l widi~ spng 4' X I 'ito 6'
6'previulyigs. d4 4 n 6 latns
Tre i distii galet'r wt erellt' i ts r i it inc1 1114 11f ill w t sII i lii
spainIlgs.
I'iirk thJil n in (ag i' S it 121 nl lii tI5 I t'euctd totalJ
pl]]) od l it ildl. I T'ltw h illr tile thirniit , the g1 tattr tile
thuiigs (ae 1)i I x I n 'X W lnig o
thitn iti'(i itiir ] 11 ias lo1e than tatii o ii pltng
t iti] tyilte orliiit ne 5 tinn jl)l'ltS S rttdit.
tili'h It is e iitt ce itug not coc14S.tatfrt hn
['iiir at ot ititit ii 1 11111(' 1 ii 1 94 it!e til 15t,'i' its 18
t's tIJllhiit sIpesenlltte llg ur ic not hilg hise 'd e p u iood
t ittt'tl-'
Til l lii'' yi r li i m11 5l it i 'u t s i c ( l i ft r n c 51111 I i n s 111 iftylil
lu m s fo dtls iffren it ing 11 Il tiiIm ti lll o 
lSitt
'ttlcbcvou eyed aprnl]are ncsl
'ii,'
f
LITERATURE CITED
(1) BENNETT, FRANK. Growth of Slash Pine Plantations on
the George Walton Experiment Forest. Station Paper No.
66. Southeastern Forest Experiment Station. 1956.
(2) DEVALL, WILBUR B. Invasion of Longleaf Pine Site by
Slash Pine and Inferior Hardwoods. Journal of the Ala-
bama Academy of Science, Vol. 22. Montevallo. 1952.
(3) FOLSOM, REID I. The Effects of Fire on Pine Plantations.
Highlights of Agricultural Research, Vol. 8. No. 1, Spring
1961.
(4) GILMORE, A. R., AND LIVINGSTON, KNOX W. Cultivating
and Fertilizing a Slash Pine Plantation: Effects on Vol-
ume and Fusiform Rust. Journal of Forestry, Vol. 56 No.
7, July 1958.
(5) HARLOW, WILLIAM M., AND HARRAR, ELLWOOD S. Text-
book of Dendrology. McGraw-Hill. New York. 1941.
(6) LITTLE, ELBERT L., AND DORMAN, KEITH W. Slash Pine
(Pinus elliottii), Including South Florida Slash Pine,
Nomenclature and Description. Station Paper No. 36.
Southeastern Forest Experiment Station. Asheville, N.C.
April 1954.
(7) LIVINGSTON, K. W. Thin-or Not to Thin? Highlights
of Agricultural Research, Vol. 3 No. 3. Fall 1956.
(8) ----------------------------.... Reproduction of Slash Pine Outside
its Natural Range. Journal of Forestry, Vol. 54 No. 8,
August 1956.
(9) _ , AND CAROTHERS, J. E. Pines Pay.
Highlights of Agricultural Research, Vol. 2, No. 3, Fall
1955.
(10) Society of American Foresters. Forest Cover Types of
North America: Report of the Committee on Forest
Types. Washington, D.C. 1954.
(11) STAHELIN, RUDOLPH. The Conversion of Hardwood to
Pine Stands in Alabama. The Journal of the Alabama
Academy of Science, Vol. 18. May 1946.
(12) United States Department of Agriculture, Forest Service.
Volume, Yield, and Stand Tables for Second-Growth
Southern Pines. U.S. Dept. Agr. Misc. Pub. 50. Wash-
ington, D.C. 1929.
(13) United States Department of Agriculture, Climate and
Man, Yearbook of Agriculture. Washington, D.C. 1941.
(14) . Forest Products
Laboratory. Wood 
Handbook. Washington, 
D.C. 1955.
(15) WARE, L. M., AND STAHELIN, R. Growth of Southern
Pine Plantations at Various Spacings. Journal of Forestry,
Vol. 46 No. 4, April 1948.
[25]
APPENDIX A
Summaries of developmental factors and yields at different ages of the individual plots in the slash pine spacing plan-
tations are presented in the following tables. All values are on a per acre basis.
APPENDIX TABLE A 1. SLASH PINE PLANTED AT 4' X 4' SPACING AND NOT THINNED (PLOT 81A3)
Total stand Stand 3.6 inches d.b.h. and larger
Planta- Operation Merch. volume
tion age or status Trees Av. Av. ht. 
Basal Trees Av. Av ht. Basal Total
diam. area diam. area vol. Pulp- Sawlogs
wood
Years Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.'
0 Planted 2,688 --- 
----
2 Re-plant. 1,004
2 After re-. 2,688 
..----- - --
3 Living 2,540 3
7 Living 2,340 2.3 70 280 4.0 24 425
11 Cut (salv.) 112 4.0 10 112 4.0 10 196 2.8
11 Left 2,108 3.1 25 112 .. ..-- _-
12 Living 2,100 3.7 33 159 996 4.9 183 2,420-
14 Living 2,052 4.0 181 1,052 5.2 .. 156 2,899
19 Living 1,236 5.4 49 197 1,008 5.8 50 188 3,649 46.3 5,510
24 Living 980 6.2 53 208 916 6.4 55 206 4,698 61.2 11,450
31 Living 792 7.0 60 215 708 7.4 64 212 6,028 77.8 20,550
31-year production... .. .... . 6,224 80.1
SInternational 1/4" Rule, trees of 7" diameter class and larger.
APPENDIX TABLE A 2. SLASH PINE PLANTED AT 4' X 4' SPACING AND THINNED ONCE-LATER COMMERCIAL THINNINGS
AT PLANTATION AGE 19 YEARS (PLOT 82C4)
Total stand Stand 3.6 inches d.b.h. and larger
Planta- Operation
tion age or status
Trees Av. 
Av ht. Basal 
Trees Av. 
Av ht. Basal 
Total Merch. 
volume
diam. area diam. area vol. Pulp- Sawlogs
wood
2,6
2,4
Cut (salv.) 1
Left 1,9
Living 1,9
Living 1,9
Cut (thin.) 5
Left 7
Living 4
Living
31-year production
Number In. Ft. Sq. ft. Number In.
2,688 .. -
626
2,688
320 .
196 2.4
12 4.4
84 3.0
36 3.6
00 3.9
20 4.6
720 5.5
112 6.9
368 8.2
- 79 292 4.1
12 112 4.4
25 98
32 186 848 4.8
159 936 5.1
59 392 5.0
49 117 516 6.3
52 106 304 7.8
58 135 308 8.9
Ft. Sq. ft. Cu. ft. Cords Bd. ft.'
27 464 _
12 244 3.2 _
105 1,909
131 2,425 ..
53 966 14.1
50 110 2,149 27.9 3,740
60 101 2,480 30.7 8,150
65 132 3,800 47.1 15,880
5,010 64.4
SInternational 1/4" Rule, trees 
of 7" diameter class and larger.
[26 1
Planted
Re-plant.
After re-.
Living
Living
Years
0
2
2
3
7
11
11
12
14
19
19
24
31
,,,,, rr r\
APPENDIX TABLE A 3. SLASH PINE PLANTED AT 4'X 4' SPACING AND THINNED TWICE-PRE-COMMERCIAL THINNING AT AGE 8 YEARS
AND LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 32C5)
Total stand
Planta- Operation
tion age or status
Years
0
2
2
3
7
8
8
10
12
14
19
19
24
31
Planted
Re-planted
After re-.
Living
Living
Cut (thng.)
Left
Living
Living
Living
Cut (thng.)
Left
Living
Living
Trees YAv.
Tes diam.
Number
2,688
54
2,688
2,628
2,444
1,704
740
660
660
648
308
324
284
280
In.
2.4
2.0
3.3
4.3
5.0
5.5
5.9
7.0
8.3
9.2
Stand 3.6 inches d.b.h. and larger
Av. 
ht. 
Basal
area
Trees EAv.
Tes diam.
Ft. Sq. ft. Number
73
___ 36
_ 44
31 67
___ 89
___ 108
___ 58
53 86
63 107
70 130
In.
280 4.1
640
628
300
320
280
272
5.0
5.6
5.9
7.0
8.4
9.4
Av. ht. 
Basal 
Total
area vol. Pulpd Sawlo
Ft. Sq. ft. Cu. ft. Cords Bd. f t.
-- 26 446 --- - --
---- 7121' -- --
53
64
71
89
108
58
86
107
130
31-year production
1,628
2,008
1,068
1,716
2,760
3,949
5,7292
14.5
22.1
34.8
48.7
63.2
4,280
10,230
17,300
1 Includes trees 
to the 2-inch 
diameter class.
2 Includes the small, but unknown, volume in 2 and 3 inch trees cut at age 8.
' International 1/4" rule, trees of 7" diameter class and larger.
APPENDIX TABLE A 4. SLASH PINE PLANTED AT 4' X 4' SPACING AND THINNED TWICE-PRE-COMMERCIAL THINNING AT AGE 8 YEARS
AND LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 31B4 )
Total stand
Planta- Operation
tion age or status
Years
0
2
2
3
7
8
8
10
12
14
19
19
24
31
e Av.
Tes diam.
Number In.
Planted 2,688 --
Re-planted 1,145 --
After re-. 2,688 --
Living 2,496
Living 2,356 2.5
Cut (thng.) 1,632 2.5
Left 724 3.5
Living 720 4.6
Living 704 4.9
Living 692 5.5
Cut (thng.) 320 5.7
Left 312 7.2
Living 284 7.9
Living 260 9.2
31-year production __
Av. ht. 
Basal
area
Ft. Sq. ft.
30
33
53
61
69
77
57
48
83
94
115
57
89
98
119
Stand 3.6 inches d.b.h. and larger
Tes Av. .h. 
Basal Total 
Merch. volume
Tes diam. A.h. area vol. Pu 
Swlog
Number In. Ft. Sq. ft. Cu. 
ft. Cords Bd. ft.3
312 4.1
672
684
316
312
284
260
5.0
5.5
5.7
7.2
7.9
9.2
53
61
69
29 512
___ 6161-
93 1,674
115 2,137
56 1,071
89 1,828
98 2,404
119 3,462
-__ 5,1492
14.2
23.1
30.5
42.9
57.1
4,920
8,310
14,630
'Includes trees to the 2-inch diameter class.
Includes the small, but unknown, 
volume in 2 and
' International 
1/A" rule.
3 inch trees cut at age 8.
[27]
In \Ii r;in I I
APPENDIX TABLE A 5. SLASH PINE PLANTED AT 4' X 4' SPACING AND THINNED TWICE-PRE-COMMERCIAL THINNING AT AGE 8 YEARS
AND LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 31B8)
Total stand Stand 3.6 inches d.b.h. and larger
Planta- Operation Merch. volume
tion age or status Trees Av. 
Av. ht. Basal Trees Av. Av. ht. Basal 
Total
diam. area diam. area vol. Pulp Sawlogs
wood
Years Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.
3
0 Planted 2,688 - -
2 Re-planted 747
2 After re-. 2,688
3 Living 2,568 ____ 2
7 Living 2,416 2.5 80 372 4.1 34 602
8 Cut (thng.) 1,700 2.6 62 560'
8 Left 716 3.6 50
10 Living 692 4.4 33 74 -
12 Living 684 5.2 35 100 672 5.2 99 1,118
14 Living 672 5.6 114 668 5.6 113 2,117
19 Cut (thng.) 356 5.8 64 356 5.8 64 1,217 16.2
19 Left 304 7.1 53 83 300 7.1 53 83 1,693 21.5 4,460
24 Living 280 7.8 61 92 280 7.8 61 92 2,374 30.0 8,120
31 Living 276 9.0 70 122 276 9.0 70 122 3,602 44.7 15,020
31-year production ___5,3792 60.9
Includes trees to the 2-inch diameter class.
SIncludes the small, but unknown, 
volume in 2 and
' International 
14" rule.
3 inch trees cut at age 8.
APPENDIX TABLE A 6. SLASH PINE PLANTED AT 4' X 4' SPACING AND THINNED TWICE-PRE-COMMERCIAL THINNING AT AGE 8 YEARS
AND LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 32C6)
Total stand Stand 3.6 inches d.b.h. and larger
Planta- Operation . Basal Av. Basal Total Merch. volume
tion age or status Trees Av. Av. ht. Basal Trees Av. Av. ht. Basal Total Pul -
diam. area Trees diam. area vol. Pulp- Sawlogs
wood gs
Years Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.
3
0
2
2
3
7
8
8
10
12
14
19
19
24
31
Planted
Re-planted
After re-.
Living
Living
Cut (thng.)
Left
Living
Living
Living
Cut (thng.)
Left
Living
Living
2,688
341
2,688
2,652
2,376
1,636
740
680
680
680
292
372
872
360
2.2
2.4
3.0
3.9
4.5
5.1
5.3
6.4
7.4
8.3
31-year production __
1 Includes trees to the 2-inch diameter class.
2 Includes the small, but unknown, 
volume in
3 International 1/4" rule.
28
51
54
63
64
49
36
58
76
94
44
83
110
134
216
560
648
292
364
356
348
4.1
4.8
5.1
5.3
6.5
7.5
8.4
2 and 3 inch trees cut at age 8.
[ 28
19
71
_ N93
44
52 83
56 110
64 134
337
5681
1,296
1,723
789
1,635
2,403
3,582
4,939
10.9
21.1
29.4
44.8
55.7
2,840
6,840
13,440
APPENDIX TABLE A 7. SLASH PINE PLANTED AT 6' X 6' SPACING AND NOT THINNED (PLOT 32C13)
Total stand Stand 3.6 inches d.b.h. and larger
Planta- Operation Basal Total Merch. volume
tion age or status Trees dAv. Av. ht. Basal Trees Av. Av. ht. Basal Total Pul
diam. area diam. area vol. Pulp- Sawlo
wood 
Sawlogs
Years Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.'
Planted 1,2
After re-. 1,2
Living 1,1
Living 1,1
Cut (Salv.) 1
Left 1,0
Living 1,0
Living
Living8
Living7
Living6
31-year production
16
216
60
40 3.1
20 5.4
)08 4.3
)04 4.8
992 5.5
864 6.4
788 7.1
568 7.7
58
19
30 100
34 127
163
54 192
56 216
65 217
328
120
716
752
732
696
604
4.2
5.4
5.4
6.1
6.9
7.5
8.1
31 548
_ 19 332 4.0
_ 116 2,182
_ 154 2,881
55 186 4,049 52.5 10,120
58 212 5,112 64.8 16,540
68 214 6,432 81.2 24,890
... 6,764 85.2
1 International 
1/4" rule.
APPENDIX TABLE A 8. SLASH PINE PLANTED AT 6' X 6' SPACING ON EXCEPTIONAL SITE AND NOT THINNED (PLOT 31A1, 6' X 6'E)
Total stand Stand 3.6 inches d.b.h. and larger
Planta- Operation
tion age or status
Planted 1,2
After re-. 1,2
Living 8
Living 8
Cut (salv.)
Left 6
Living 6
Living 5
Living 3
Living 2
Living 2
31-year production
BaalMerch. volume
Trees diam. Av. ht. area Trees div Av. ht. Basal 
Total l
d area diam. area vol. Pulp- Sawlo
wood Sawlogs
Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.'
216
16 -
32
08 2.9
48 5.5
380 4.7
28 5.4
20 6.7
64 8.3
,72 9.7
08 11.6
3 -
- 36 164 4.2
8 48 5.5
31 83 --- -
36 98 500 5.8
- 127 496 6.8
57 136 356 8.4
65 141 264 9.9
80 152 204 11.7
16 804
8 156 2.0
93 1,808-
126 
2,325
57 136 3,093 38.1 11,080
66 140 3,935 47.9 17,460
81 152 5,123 61.7 25,980
_ 5,279 63.7
1 International 1/4 rule.
E[29
0
2
3
7
11
11
12
14
19
24
31
Years
0
2
3
7
11
11
12
14
19
24
31
APPENDIX TABLE A 9. SLASH PINE PLANTED AT 6X 6' SPACING AND THINNED ONCE-LATER COMMERCIAL
THINNING AT AGE 19 YEARS (PLOT 32C 1)
Total stand Stand 3.6 inches d.b.h. and larger
Planta- Operation
tion age or status
Years
0 Planted
2 After re-.
3 Living
7 Living
11 Cut (salv.)
11 Left
12 Living
14 Living
19 Cut (thng.)
19 Left
24 Living
31 Living
31-year produc
1'International 1/" rule.
Te da. A Basal A. Avalhtal Merch. volume
Trees 
area ht. Trees 
dav. A 
asal vol
area. vol. Pulp l
wood awg
Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.'
1,216 -- -- -- -- ---
1,216 ---- -- -----
1,120 -- 2 -- -- --- --
1,048 2.7 ____ 42 228 4.2 22 380 - -
76 5.2 __ 11 76 5.2 ___ 11 200 2.4
944 4.0 27 81 -- --- ----- - -- -- - --
928 4.5 32 105 628 5.3 -__- 94 1,775 _-- _-
884 5.3 33 133 664 5.9 __ 125 2,338 --- --
348 5.5 __ 57 292 5.9 _- 55 925 11.9 --
400 6.9 48 103 328 7.5 49 101 1,889 23.0 5,320
316 7.8 52 105 272 8.3 56 103 2,354 29.1 8,730
288 8.7 56 118 260 9.1 59 117 3,034 37.1 12,710
tion-__ -- --- -- 4,159 51.4 _--
APPENDIX TABLE A 10. SLASH PINE PLANTED AT 6' X 6' SPACING AND THINNED ONCE-LATER COMMERCIAL
THINNING AT AGE 18 YEARS (PLOT 35C3, 6'X 6'D)
Total stand Stand 3.6 inches d.b.h. and larger
Planta- OperationMerh.vlu
tion age or status Trees Av. 
Av ht. Basal Trees Av. Av. ht. 
Basal Total
diam. area Te diam. area vol. Pulp- Sawlo
Years Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. 
ft.'
0 Planted 1,216 --- - -- -- --- - -- ---- ---- ----
2 Re-planted 52 --- -- ----- --- -- --- -- ---
2 After re-. 1,216 --- - -- --- ----- --- - -- -
6 Living 1,124 1.8 __ 20 12 4.0 __ 1 18 ___ --
9 Living 1,072 3.0 21 52 240 4.3 -_ 24 436- -
10 Cut (salv.) 52 4.0 _- 4 52 4.0 -- 4 64 0.4 ---
14 Living 988 4.7 36 117 716 5.2 -_ 107 1,974 19.2 ---
18 Cut (thng.) 464 4.9 _- 62 368 5.3 _- 57 890 11.8 --
18 Left 488 5.9 44 94 404 6.4 46 91 1,582 17.1 2,780
24 Living 488 6.9 49 128 404 7.5 52 125 2,592 31.9 7,532
31 Living 456 8.2 57 166 408 8.6 61 164 4,122 51.1 15,680
31-year production _- -_ _-_- _-_ __ -_ __ 5,076 63.3 -_
1'International 14" rule.
[80J
It (
APPENDIX TABLE A 11. SLASH PINE PLANTED AT 6' X 6' SPACING AND THINNED TWICE-LIGHT, EARLY COMMERCIAL 
THINNING
AT AGE 12 YEARS AND LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 31B1)
Planta- Operation
tion age or status
Years
0
2
3
7
11
11
12
12
14
19
19
24
31
Total stand
Tree Av
Tes diam.
Number In.
Planted 1,216
After re-. 1,216
Living 1,172
Living 1,144
Cut (salv.) 68
Left 1,076
Cut (thng.) 432
Left 612
Living 596
Cut (thug.) 248
Left 288
Living 264
Living 264
31-year production
SIncludes trees to the 2-inch class.
2 Includes the small, 
but unknown,
' International 
14" rule.
3.1
5.3
4.3
3.8
5.3
6.2
6.6
7.6
8.7
9.6
Av. 
ht. 
Basal
area
Stand 3.6 inches d.b.h. and larger
TreesTAv.
Tes diam.
Ft. Sq. ft. Number In.
____ 60
___ 10
32 107
___ 34
36 92
___ 125
55
63
72
60
90
108
134
320
68
572
588
244
288
264
264
4.3
5.3
5.4
6.2
6.7
7.6
8.7
9.6
A t 
Basal 
Total 
Merch. 
volume
A h area 
vol. Pulp-
wood a g
Ft. Sq. ft. Cu. ft. Cords Bd. ft.'
33
10
55
63
72
90
125
60
90
108
134
590
248
5801
1,719
2,345
1,243
1,958
2,847
4,164
3.2
4.4
15.6
16.3
24.6
35.3
51.2
5,750
11,030
18,900
6,235' 75.1
volume in 2- and 3-inch trees cut at age 12.
APPENDIX TABLE A 12. SlAsH PINE PLANTED AT 6' X 6' SPACING AND THINNED TWICE-LIGHT, EARLY COMMERCIAL THINNING
AT AGE 12 YEARS AND LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 31A5)
Total stand
Planta- Operation
tion age or status
Years
0
2
3
7
11
11
12
12
14
19
19
24
31
Planted
After re-.
Living
Living
Cut (salv.)
Left
Cut (thng.)
Left
Living
Cut (thng.)
Left
Living
Living
T s Av.
Tes diam.
Number In.
1,216 -
1,216 --
892 -
800 2.1
32 5.5
752 3.6
144
608
608
224
360
344
312
31-year production
1 Includes trees to the 
2-inch class.
' Includes the small, 
but unknown,
' International 
1/4" rule.
3.3
4.5
5.3
5.8
6.7
7.8
9.3
Stand 3.6 inches d.b.h. and larger
Av. ht.
area
Trs Av.
Tes diam.
Ft. Sq. ft. Number In.
--- 19
--- 5
24 54
-- - 8
32 67
--- 93
--- 40
53 88
55 114
66 147
60
32
Basal 
Total 
Merch. 
volume
A.h. area vol. Pulp- 
Sw
wood 
Swogs
Ft. Sq. ft. Cu. ft. Cords Bd. ft.3
4.0
5.5
428 5.1
500 5.7
200
328
328
312
6.0
7.0
8.0
9.3
54
56
66
60
89
39
87
113
147
40
1241
1,053
1,664
0.4
.8
9.2
806 10.8
1,850 23.7
2,624 33.7
4,128 50.7
5,098' 62.7
4,580
9,580
17,540
volume in 2- and 3-inch trees cut at age 12.
[31]1
ol O~A n~ r10
APPENDIX TABLE A 13. SLASH PINE PLANTED AT 6' X 6' SPACING AND THINNED TWICE-LIGHT, EARLY COMMERCIAL THINNING
AT AGE 12 YEARS AND LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 32C7)
Total stand Stand 3.6 inches d.b.h. and larger
Planta- Operation 
Merch. volume
tion age or status Trees A.v. A ht. Basal Trees Av. Av. ht. Basal Total
diam. area diam. area vol. Pulp- Sawlo
wood 
Sawlogs
Years Number In. Ft. Sq. ft. Number In. Ft. 
Sq. ft. Cu. ft. Cords Bd. ft.'
0 Planted 1,216 .. .. 
---.
2 After re-. 1,216
3 Living 1,184 - 2 ___....--
7 Living 1,128 2.6 ____ 41 136 4.2 13 224
11 Cut (salv.) 104 4.7 12 104 4.7 12 248 8.2
11 Left 1,024 3.7 25 77
12 Cut (thng.) 416 3.6 ____ 30 4642 
2.4 -
12 Left 600 4.7 31 74 516 5.0 70 1,331 10.0
14 Living 596 5.5 97 528 5.7 94 1,758 _
19 Cut (thng.) 264 5.7 46 244 5.8 45 890 12.3
19 Left 316 6.9 541 81 296 7.1 54 80 1,707 21.9 4,180
24 Living 312 7.7 521 101 288 8.0 54 100 2,128 26.5 6,950
31 Living 300 8.8 62 127 _ 296 8.9 62 127 3,283 40.5 13,060
31-year production ... . -_4,8853 58.4
1 Discrepancy is due to sampling. The age 19 average 
height is based on a sample. The age 24 average 
height is based on meas-
urement of all trees.
2Includes trees to the 2-inch class.
SIncludes the small, but unknown, volume in 2- and 3-inch trees cut at age 12.
SInternational 1/i " rule.
APPENDIX TABLE A 14. SLASH PINE PLANTED AT 6' X 6' SPACING AND THINNED TWICE-LIGHT, EARLY COMMERCIAL THINNING
AT AGE 12 YEARS AND LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 32C2)
Total stand Stand 3.6 inches d.b.h. and larger
Planta- Operation Merch. volume
tion age or status Trees Av. Av ht. Basa Trees Av. Av ht. Basal Total M
diam. area diam. area 
vol. Pulp- Sawlogs
wood ogs
Years Number In. Ft. Sq. ft. Number In.
0 Planted 1,216 .. .. ..
2 After re-. 1,216 ._.. .... ....
3 Living 1,180 ... 3
7 Living 1,124 3.1 58 340 4.2
11 Cut (salv.) 92 4.9 12 92 4.9
11 Left 1,024 4.2 28 97 _
12 Cut (thng.) 412 4.4 _ 44 196 5.3
12 Left 596 5.2 33 88 552 5.3
14 Living 596 5.9 112 564 6.0
19 Cut (thng.) 252 5.7 44 244 5.7
19 Left 244 7.9 56 84 244 7.9
24 Living 224 9.2 62 103 224 9.2
31 Living 220 10.1 69 122 220 10.1
31-year production ___.
1 Includes trees to 
the 2-inch class.
2 Includes the small, but unknown, volume 
in 2- and 3-inch trees cut at age 12.
International 
1/4" rule.
Ft. Sq. ft. Cu. 
ft. Cords Bd. 
ft.
3
-.- 33 132 ....
12 272 4.0 --
31 6641 4.4 -
85 1,583 13.6
-- 110 2,062-
43 884 11.9
56 84 1,810 22.6 5,700
62 103 2,582 30.8 10,040
69 122 3,588 42.9 15,930
.. 5,3582 63.2 -
[32 ]
APPENDIX TABLE A 15. SLASH PINE PLANTED AT 6' X 6' SPACING AND THINNED TWICE-HEAVY, EARLY COMMERCIAL THINNING
AT AGE 12 YEARS AND LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 32C3)
Stand 3.6 inches d.b.h. and larger
Planta- Operation
tion age or status
Planted 1,2
After re-. 1,2
Living 1,2
Living 1,1
Cut (salv.) 1
Left 1,C
Cut (thng.)
Left 4
Living 4
Cut (thng.) 1
Left 2
Living 1
Living 1
31-year production
Trees Av. 
Av ht. Basal 
Trees Av. 
Av ht. Basal 
Total Merch. 
volume
diam. area diam. area vol. Pulp-Sawlogs
wood ogs
Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.'
216 -
216 -
08 -
180 3.4
120 4.6
)28 4.4
584 4.3
432 5.8
16 6.7
.56 7.5
16 8.0
184 9.4
.84 10.7
73 496 4.3
14 120 4.6
30 109 - --
60 -
35 78 412 5.8
101 408 6.7
48 156 7.5
55 76 212 8.1
62 88 180 9.5
69 115 180 10.8
50 221
14 276 3.2
_ 9561 6.0 ..
_ 77 1,490 11.6 .
S 101 1,886 _ _
48 996 12.0
55 76 1,629 19.4 5,410
63 88 2,247 27.0 9,210
70 115 3,379 40.8 15,860
.... .. 5,607' 62.0
' Includes trees to the 2-inch class.
'Includes the small, but unknown, volume in 2- and 3-inch trees cut at age 12.
3 International 
1/4" rule.
APPENDIX TABLE A 16. SLASH PINE PLANTED AT 6' X 6' SPACING AND THINNED TWICE-HEAVY, EARLY COMMERCIAL THINNING
AT AGE 12 YEARS AND LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 31B5)
Total stand Stand 3.6 inches d.b.h. and larger
Planta- Operation
tion age or status
Planted
After re-. 1,2
Living 1,1
Living 1,0
Cut (salv.)
Left 9
Cut (thng.) 5
Left 4
Living 4
Cut (thng.) 1
Left 2
Living 2
Living 2
31-year production
Trees Av. 
Av ht. Basal 
Trees Av. 
Av ht. Basal 
Total Merc. 
volume
diam. area diam. area vol. Pulp Sawlogs
wood awogs
Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.'
1,216..... .
116
00 _
)44 2.8
56 4.4
68 3.9
524 4.1
148 5.3
140 6.2
.56 6.5
72 7.8
52 9.0
40 10.1
- 46 204 4.2
6 56 4.4
27 81
48 284 4.8
32 70 416 5.5
--- 92 420 6.3
36 152 6.6
55 90 272 7.8
61 110 252 9.0
70 133 240 10.1
20 350
6 128 1.6
35 6071 4.4
69 1,320 10.0
S 91 1,718-_
36 718 9.2
55 90 1,897 22.5 5,900
61 110 2,738 33.4 11,110
70 133 3,897 47.6 17,570
... -. 5,350' 62.8 -
1 Includes trees to the 2-inch class.
2 Includes the small, but unknown, 
volume in 2- and 3-inch trees cut 
at age 12.
3 International 
1/4" rule.
[33]
Total stand
Years
0
2
3
7
11
11
12
12
14
19
19
24
31
Years
0
2
3
7
11
11
12
12
14
19
19
24
31
riwiiiw, ~ llr
--- -- - --- --,I,,
APPENDIX TABLE A 17. SLASH PINE PLANTED AT 6' X 6' SPACING AND THINNED TWICE-HEAVY, EARLY COMMERCIAL THINNING
AT AGE 12 YEARS AND LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 31B2)
Total stand Stand 3.6 inches d.b.h. and larger
Planta- Operation T Merch. volume
tion age or status Trees am. Av. ht. Basal Trees Av. Av. ht. Basal Total Pul
diam. area diam. 
area vol. Pulp- Sawlogs
wood
Years Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.'
Planted 1,2
After re-. 1,2
Living 1,1
Living 1,0
Cut (salv.)
Left 1,C
Cut (thng.) 6
Left 4
Living3
Cut (thng.) 1
Left 2
Living2
Living 2
31-year production
16
16 --
.20
)84 3.0
32 4.0
)32 4.1
332 4.3
100 5.6
396 6.3
16 6.9
252 7.9
224 9.1
216 10.5
.... 52 264 4.2
3 32 4.0
30 98 .---
62
35 68 368 5.7
86 376 6.4
30 116 6.9
55 86 248 8.0
66 101 224 9.1
72 130 216 10.5
6 420 ...
3 56 0.8
- -- 9001 6.0 -
. 66 1,244 10.4
85 1,590
30 604 7.5
55 86 1,823 22.2 6,250
66 101 2,750 33.9 11,300
72 130 3,927 47.6 18,240
... 5,4872 61.9
1 Includes trees to the 2-inch diameter class.
2 Includes the small, but unknown, volume in 2 and 3 inch trees cut at age 12.
3 International 
1/4" rule.
APPENDIX TABLE A 18. SLASH PINE PLANTED AT 6' X 8' SPACING AND THINNED TWICE-LIGHT, EARLY COMMERCIAL THINNING
AT AGE 14 YEARS AND LATER COMMERCIAL THINNING AT AGE 18 YEARS (PLOT 35A7)
Total stand Stand 3.6 inches d.b.h. and larger
Planta- Operation Merch. volume
tion age or status Trees d . Av. ht. Basal Trees 
V. Av. ht. asal Total Pulp
wood
Years Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.
0 Planted 896 ..- -- -
2 Re-planted 56 ..- ---------
2 After re-. 896 ..... .
6 Living 844 2.2 _ 23 16 4.0 -1 23 ....
9 Living 820 3.7 23 60 472 4.3 -- 48 880 6.3
14 Cut (thng.) 168 5.6 29 152 5.8 28 484 6.3 -
14 Left 636 5.4 39 103 556 5.7 100 1,694
18 Cut (thng.) 252 6.0 50 244 6.1 49 837 10.9 -
18 Left 364 6.6 47 88 324 7.0 48 86 1,574 19.7 3,650
24 Living 336 7.8 52 110 304 8.1 55 109 2,392 29.5 8,120
31 Living 328 8.9 60 142 304 9.2 63 141 3,682 45.2 14,010
31-year production .. ... . 5,003 62.4 --
1 International 
1/4" rule.
[34 ]
0
2
3
7
11
11
12
12
14
19
19
24
31
APPENDIX TABLE A 19. SLASH PINE PLANTED AT 6' X 8' SPACING AND THINNED TWICE-HEAVY, EARLY COMMERCIAL THINNING
AT AGE 14 YEARS AND LATER COMMERCIAL THINNING AT AGE 18 YEARS (PLOT 35B7)
Total stand
Planta- Operation
tion age or status
Planted
Re-planted
After re-.
Living
Living 7
Cut (thng.) 2
Left 4
Cut (thng.) 14
Left2c
Living 24
Living2
31-year production
Stand 3.6 inches d.b.h. and larger
Basal Total 
Merch. volume
Trees dav. A. ht. aseal Trees dav. Av. ht.Pup
dim ae da.area vol. wood- 
Sawlogs
Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.'
84 - --
)8 2.4
76 3.7
68 5.3
56 5.8
48 6.5
)6 7.0
[4 8.2
36 9.4
____ 24 32 4.0
23 58 476 4.3
41 256 5.4
40 84 408 6.1
___ 34 144 6.6
41 80 276 7.3
50 89 228 8.4
58 113 220 9.7
--- 3 13 -- - -
48 780 6.0 ---
--- 40 660 8.4 --
--- 82 1,332 --- --
34 498 6.2
41 79 1,202 14.6 2,960
52 89 1.865 22.5 6,600
60 112 2,844 34.1 12,000
____ ____ 4,002 48.7 --
1 International 
14" rule.
APPENDIX TABLE A 20. SLASH PINE PLANTED AT 8' X 8' SPACING AND THINNED ONCE-LATER COMMERCIAL THINNING
AT AGE 19 YEARS (PLOT 32C9 )
Total stand Stand 3.6 inches d~b~h. and larger
Planta- Operation _________volume_
Hion age or status Trees Av. Av. ht. 
Basal Trees Av.. Av, ht. Basal Total 
MecP vlm
diam. area diam. area vol. Pulp- Sa 1
wood w 
gs
Years Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.'
Planted 6'1
After re-. 6'
Living 64
Living 6(
Cut (salv.)
Left 54
Living 5z
Living 54
Cut (thng.) 2
Left 
21
Living 2"'
Living 2'
31-year production
72 --
72 --
44 _---
)0 2.5
52 4.6
48 4.0
48 4.8
40 5.5
28 6.3
72 7.0
72 7.7
72 8.4
2 -- - - - -
--- 20 76 4.0
6 52 4.6
23 48 --- --
28 69 412 5.3
38 89 452 5.9
49 216 6.4
48 72 248 7.2
50 88 248 8.0
58 104 248 8.7
7 108 ____ ____
6 96 1.2 -_-
___ 64 1,120 _-_ -_
___ 85 1,474 ___
___ 48 883 11.3 ---
49 . 71 1,348 16.8 3,750
52 87 1,826 22.7 5,970
61 103 2,602 32.1 10,130
____ ____ 3,581 44.6 __
'International 14" rule.
[35]J
Years
0
2
2
6
9
14
14
18
18
24
31
0
2
3
7
11
11
12
14
19
19i
24
31
APPENDIX TABLE A 21. SlAsH PINE PLANTED AT 8' X 8' SPACING AND THINNED ONCE-LATER COMMERCIAL THINNING
AT AGE 19 YEARS (PLOT 32C8)
Total stand
Planta- Operation
tion age or status
Years
0
2
3
7
11
11
12
14
19
19
24
31
Stand 3.6 inches d.b.h. and larger
s Av. A 
ht Basal 
T e Av 
. Basal 
Total Merch. 
volume
da.area diam. area vol. Pup 
Sawlog
wood og
Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.'
Planted 672 -- - -- --- - - -
After re-. 672 ------
Living 660 ---- 2 -- - --- 
--
Living 628 2.4 _-- 20 64 4.1 _-_ 6 91_ -_-
Cut (salv.) 56 5.6 - 10 56 5.6 -- 10 100 1.2 --
Left 560 3.9 23 46 -_- _- -_ - _- ___ -_- ---
Living 560 4.6 29 65 412 5.2 __ 60 1,024 ___ --
Living 556 5.3 38 84 452 5.7 -- 80 1,378
Cut (thng.) 236 5.7 -- 41 216 5.8 -_ 40 705 9.3 --
Left 276 6.6 47 66 236 7.1 48 65 1,208 15.2 3,160
Living 260 7.6 51 83 228 8.1 54 81 1,746 21.8 5,940
Living 248 8.4 59 96 224 8.8 63 95 2,529 31.1 9,890
31-year production - - -- _ -_ --- __ 3,334 41.6 --
International 14" rule.
APPENDIX TABLE A 22. SLASH PINE PLANTED AT 8' X 8' SPACING AND THINNED ONCE-LATER COMMERCIAL THINNING
AT AGE 19 YEARS (PLOT 31A4)
Total stand Stand 3.6 inches d.b.h. and larger
Plantera- in Opeatione
Planta- OperationAV . Basal TAV . Basal Total Merch. volume
tidn 
aaaa 
or ste 
v.ls 
Trees 
s 1t.ae 
T s a 
A h. ral 
Pp wo
wood a g
Years Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.'-
0 Planted 672 - --- -- --- - --- - -- - - -
2 After re-. 672 ----- --- - --- ------ -
3 Living 524 --- 2 -- -- - - - ---- - -- - -
7 Living 488 2.5 __ 16 64 4.0 -___ 6 93 ___ --
11 Cut (salv.) 32 4.8 __ 4 32 4.8 __ 4 84 1.2 --
11 Left 456 4.8 26 45 ___ ___ -__ __ __ _-
12 Living 452 5.2 34 66 340 5.8 __ 62 1,069 __- _-
14 Living 448 5.9 43 84 364 6.4 __ 80 1,416 _-_ --
19 Cut (thng.) 152 6.4 __ 34 128 6.8 __ 32 620 7.8 ---
19. Left 244 7.7 50 78 240 7.7 50 78 1,535 18.8 4,900
24 Living 216 8.9 60 92 216 8.9 60 92 2,279 27.9 8,980
31 Living 212 10.0 70 116 212 10.0 70 116 3,436 42.0 15,580
31-year production __ -- __ 4,140 51.0 --
1'International 
1/" rule.
[ 36J
APPENDIX TABLE A 23. SLASH PINE PLANTED AT 8' X 8' SPACING AND THINNED TWICE-LIGHT, EARLY COMMERCIAL THINNING
AT AGE 15 AND LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 31B6)
Total volume Stand 3.6 inches d.b.h. and larger
Planta- Operation _______volume
lion age or status Trees Av. Av. ht. Basal Trees Av. Av lit. Basal Total Mrl.vlm
diam. area diam. area vol. 
Pulp- Sawlo gs
wooda
Years Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.'-
Planted 6'
After re-. 6
Living 6(
Living
Cut (salv.)
Left
Living5
Living5k
Cut (thng.) 11
Left 4]
Cut (thng.) 14F
Left 2
Living 2,
Living 21
31-year production
72 --
72 --
30 3.0
28 5.4
36 4.6
,36 5.4
32 6.1
12 6.6
:12 6.4
60 6.0
,36 7.9
36 9.2
32 10.2
28 160 4.3
4 28 5.4
28 61 --- - ---
33 86 436 5.9
45 108 460 6.5
--- 27 104 6.8
--- 91 360 6.7
31 132 6.4
57 81 232 8.0
61 109 236 9.2
69 132 232 10.2
--- 16 262 _-_ _- -
4 116 2.0 --
--- 83 1,427 ___ --
105- 1, 839 __ --
--- 26 450 5.2 __
_ 89 1520 17.4
30 562 7.1
--- 81 1,605 19.5 5,260
61 109 2,741 33.4 10,760
69 132 3,955 46.7 17,480
___: ___- 5,083 61.0 -_
1 International 
1/4" rule.
APPENDIX TABLE A 24. SLASH PINE PLANTED AT 9 /' X 91/' SPACING AND THINNED ONCE-LATER COMMERCIAL
THINNING AT AGE 19 YEARS (PLOT 31B7)
Total stand Stand 3.6 inches d.b.h. and larger
lonta age rsatuso ree Av. .h. Basal Tre Av. v lt Basal Total Merch. volume
tio ag o sttu Tres 
diam. A t area 
Tre diam. vht, 
area vol. Pulp- 
Sawlogs
wood a
Years Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.,
Planted 4
After re-. 4
Living
Living 3
Cut 
(salv.)Let3
Li i 
3Living 3E
Cut (thng.) 
c
Left 2
Living 2
Living 2
31-year production
i30
30 ----
r80 ----
34 2.6
16 5.2
68 4.3
68 5.4
64 6.2
96 7.8
44 7.9
28 9.1
20 10.4
___ 14 68 4.3
___ 2 16 5.2
26 37 __- --
32 59 304 5.9
44 77 320 6.6
___ 31 92 7.9
53 83 232 8.1
59 103 224 9.1
69 130 220 10.4
7 156 _-_ __
2 36 0.4 -
57 919 _-_ --
--- 76 1,245 ___ --
31- 655 8.0
53 83 1,717 20.9 5,750
60 102 2,536 30.4 10,100
69 130 3,717 45.0 16,940
___4,408 53.4
1 International 1/4"i rule.
[37]
0
2
3
7
11
11
12
14
15
15
19
19
24
31
0
2
3
7
11
11
12
14
19
19
24
31
APPENDIX TABLE A 25. SLASH PINE PLANTED AT 91/2 'X 91/2' SPACING AND THINNED ONCE-LATER COMMERCIAL
THINNING AT AGE 19 YEARS (PLOT 32C10)
Stand 3.6 inches d.b.h. and larger
Planta- Operation
tion age or status
Planted
After re-. 4
Living 4
Living 4
Cut (salv.)
Left 3
Living 3
Living 3
Cut (thng.) 1
Left 2:
Living 2:
iig231-year 
production
Av. A 
Basal T 
Av .
Basal Total 
Merch. volume
area vol. -Sawlogs
wood
Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. (Cords Bd. ft.'
80
160 --
156 3.3
52 4.8
[88 5.9
>88 6.2
188 6.9
.56 7.3
24 8.5
;24 9.3
,12 10.3
--- 26 160 4.3
7 52 4.8
31 74 --- --
33 80 356 6.4
43 102 364 7.1
49 152 7.4
54 89 212 8.8
59 106 212 9.6
66 122 208 10.4
16 245
7 100 1.2
___ 79 1,312 ___ __
___ 101 1,673 ___ __
46 928 11.5
55 89 1,908 23.0 7,090
61 106 2, 607 31.6 10, 900
67 122 3,390 40.9 15,380
4,418 53.6
'International 
1/4" rule.
APPENDIX TABLE A 26. SLASH PINE PLANTED AT 12' X 12' SPACING AND THINNED ONCE-LATER COMMERCIAL
THINNING AT AGE 19 YEARS (PLOT 32C1 1)
Total stand Stand 3.6 inches d.b.h. and larger
Planta- OperationMec.vlm
tion age or status Trees Av. Av. ht. Basal Trees Av. Av. ht. Basal Total 
Mec.vlm
diam. area diam. area vol. Pulp- 
5 1o g
wood a g
Years Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.'.
Planted 2
After re-. 2
Living 2
Living 2
Cut (salv.)
Left 2
Living 2
Living 2
Cut (thng.)
Left 1
Living 1U
Living 1
31-year production
38 - --
88 --
38 --
88 3.8
36 6.3
52 6.2
52 7.1
52 8.0
38 9.1
64 9.2
56 10.7
28 11.7
32
34
45
57
63
71
23 172 4.5
8 36 6.3
53 -- --
70 252 7.1
88 252 8.0
40 88 9.1
76 164 9.2
97 156 10.7
95 128 11.7
34
45
57
63
71
19 286 --- --
8 128 1.6 --
70 1,148 --- --
88 1,452 --- _-
40 899 10.6
76 1,713 20.1 6,650
97 2,504 30.5 10,800
95 2,750 32.8 13,180
-__ 3,777 45.0 __
'International 14" rule.
[38]
Total stand
Years
0
2
3
7
11
11
12
14
19
19
24
31
0
2
3
7
11
11
12
14
19
19
24
31
____ - 2Kaal I
APPENDIX TABLE A 27. SLASH PINE PLANTED AT 12' X 12' SPACING AND THINNED ONCE-LATER COMMERCIAL
THINNING AT AGE 19 YEARS (PLOT 31A2)
Total stand
Planta- Operation
tion age or status
Planted
After re-.
Living
Living
Cut (salv.)
Left
Living
Living
Cut (thng.)
Left
Living
Living
31-year product
Stand 3.6 inches d.b.h. and larger
Trees Av. Av ht. Basal Trees Av. Av ht. Basal Total Merch. volume
diam. area diam. area vol. Pulp- Sa 1
wood wog
Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.'
ante288
~terre- 288
244 - 3-- 
--
240 3.2 -- 14 84 4.4 9 139 -
24 5.8 -- 4 24 5.8 -- 4 92 1.6 ---
212 5.3 32 32 - -- -- - ---- --- ---
212 6.6 37 50 188 6.9 -- 49 805 --- --
208 7.3 46 61 192 7.6 -- 60 983 --- --
44 9.9 -- 23 40 10.4 -- 23 546 6.4 --
152 8.8 57 64 152 8.8 57 64 1,422 16.9 5,330
152 10.2 66 86 152 10.2 66 86 2,274 28.3 10,520
128 12.0 80 98 128 12.0 80 98 3,268 39.3 16,600
tion--- -- ----- --- -- 3,906 47.3
1 International 'A4" rule.
APPENDIX TABLE A 28. SLASH PINE PLANTED AT 16' X 16' SPACING AND THINNED ONCE-LATER COMMERCIAL
THINNING AT AGE 19 YEARS (PLOT 32C12)
Total stand Stand 3.6 inches d.b.h. and larger
Planta- Operation
tion age or status
Planted
After re-.
Living
Living
Cut (salv.)
Left
Living
Living
Cut (thug.)
Left
Living
Living
31-year produc
Av. v. 
v. A. 
Ttal Merch. volume
Trees diam. A. ht. ae res dAv. A. ht. aseal wood aogs
areadia. 
ara vl. Plp- 
Sawlog
Number In. Ft. Sq. ft. Number In. Ft. Sq. ft. Cu. ft. Cords Bd. ft.'
1 6 8 -- -- - - - - - - - - - - - - -- ---
1 6 8 - - 3 - ----- ----- ---- --- -
168 3.7 -- 12 104 4.3 _- 10 156 --_ --
8 8.0 -- 3 8 8.0 -- 3 36 0.4 --
156 6.4 30 35 ---- --- -------
152 7.6 34 48 148 7.7 _- 47 793 ___ --
152 8.6 44 61 152 8.6 44 61 1,000 -
40 9.2 - 19 40 9.2 19 318 4.6
112 10.5 56 67 112 10.5 56 67 1,071 17.0 5,990
112 11.9 65 87 112 11.9 65 87 2,214 26.6 10,540
100 13.0 75 93 100 13.0 75 93 2,818 33.4 14,200
tion 3,172 38.4
Inte o r / r
[39]
Years
0
2
3
7
11
11
12
14
19
19
24
31
Years
0
2
3
7
11
11
12
14
19
19
24
31
--- - -- -- ---i{.1Vai
APPENDIX TABLE A 29. SLASH 
PINE PLANTED AT 16' X 16' SPACING 
AND THINNED ONCE-LATER 
COMMERCIAL
THINNING AT AGE 19 YEARS 
(PLOT 31A6)
Total stand
Stand 3.6 inches d.b.h. and larger
riant- vpeauonMerch. volume
ion age or status TreesA 
, Basal Trees Av. 
Av. ht. B Total
d vht. area 
diam. aeal vol. 
Pulp-
wood 
Saw 
ogs
Years Number In. 
Ft. Sq. ft. Number In. Ft. Sq. 
ft. Cu. ft. Cords Bd. f t.'
Planted
After re-.
Living
Living
Cut (salv.)
Left
Living
Living
Cut (thug.)
Left.
Living
Living
31-year productio
11
11
.68
.68
i 152 3-_ -
-
20 11.6 
15 20 11.6
108 9.6 54 
54 104 9.8 54
104 11.1 66 70 
104 11.1 66
100 12.5 74 86 
100 12.5 74
5 104 ___ --
1 8 0.1 ___
32 524 
-
44 723 ___ --
15 332 3.8 --
54 1,157 13.5 4,460
70 1,942 23.2 9,140
86 2,651 31.6 13,420
___ 2,991 35.5 __
'International 
1/" rule.
APPENDIX TABLE A 30. SLASH 
PINE PLANTED AT 19' X 19' SPACING 
AND NOT THINNED (PLOT 31A7)
Total stand 
Stand 3.6 inches d.b.h. and larger
Planta- Operation 
Merch. volume
tion di rsats Tes A. 
Av. ht. Basal Trees Av. Av. ht. 
Basal Totalagemorastatus Tes A Adiam 
area vol. Pulp- d Saw 
s 1
Years Number 
In. Ft. Sq. ft. Number 
In. Ft. Sq. ft. Cu. ft. 
Cords Bd. ft.'-
0 Planted 120 _ _
2 A fter re-. 120 
--- - -- 
----- - - -- -
---- ----
3 Living 104 
- 2 
- -
7 Living 92 
2.4 3 12 
4.4 1 18
11 Cut (salv.) 4 
7.3 __ 1 4 
7.3 ___ 1 20 
0.4
11 Left 76 
4.2 23 7 __- 
- - ___- __ 
-
12 Living 76 
5.8 30 14 64 
6.3. __ 14 222 
___ --
14 Living 72 
6.9 37 19 68 
7.1 __ 19 303 ___ 
--
19 Living 72 9.4 
47 35 72 9.4 47 
35 669 7.8 2,760
24 Living 68 
11.1 60 46 68 11.1 
60 46 1,116 13.0 5,120
31 Living 68 
12.8 71 61 68 12.8 
71 61 1,778 21.0 8,800
31-year production __ __ 
__ __ __ __ __ 
1,798 21.4 --
' International 
1/4" rule.
_F 40]
0
2
3
7
11
11
12
14
19
19
24
31
---- --- --- --- --- -----
p A D a r~ro-
3n
APPENDIX B
Stand tables are presented for the individual plots in the slash pine spacing 
plantings at plantation age 31 years. Age
from seed was 32 years.
APPENDIX TABLE B 1. STAND PER ACRE AT PLANTATION AGE 31 YEARS, SLASH PINE PLANTED AT 4'X 4' SPACING AND
NOT THINNED (PLOT 81A3)
Diameter class
Inches
4
5
6
7
8
9
10
11
Dominants and codominants
Trees
Number
0
0
8
64
84
100
68
24
Basal area
Sq. feet
0.0
.0
1.6
17.1
29.3
44.2
37.1
15.8
Total 348 145.1
Average .417
Site index' 88
Based on total height of dominants and codominants.
Average height
Feet
68
69
70
72
73
76
71
Stand 3.6 in. d.b.h. and larger
Trees Basal area Average height
Number Sq. feet Feet
84 7.3 43
76 10.3 55
132 25.9 63
104 27.8 67
104 36.3 70
112 49.5 72
72 89.3 74
24 15.8 76
708 212.2
.300 64
APPENDIX TABLE B 2. STAND PER ACRE AT PLANTATION AGE 81 YEARS, SLASH PINE PLANTED AT 4' X 4' SPACING AND THINNED
ONCE-LATER COMMERCIAL THINNING AT PLANTATION AGE 19 YEARS (PLOT 32C4)
Diameter class
Inches
4
5
6
7
8
9
10
11
12
13
14
Trees
Number
0
0
0
12
20
48
48
48
16
4
4
Total 200
Average
Dominants and codominants
Basal area Av
Sq. feet
0.0
.0
.0
3.2
7.0
21.2
26.1
31.7
12.6
3.7
4.3
109.8
.549
Site index
1  
89
'Based on total height of dominants and codominants.
erage height
Feet
....
70
68
71
71
74
76
80
75
72
Stand 3.6 in. d.b.h. and larger
Trees Basal area Average height
Number Sq. feet Feet
20 1.7 33
12 1.6 38
32 6.3 59
44 11.7 63
32 11.2 66
48 21.2 71
48 26.1 71
48 31.7 74
16 12.6 76
4 3.7 80
4 4.3 75
308 132.1
.429 65
APPENDIX TABLE B 3. STAND PER ACRE AT PLANTATION AGE 31 YEARS, SLASH PINE PLANTED AT 4' X4' SPACING AND THINNED
TWICE-PRE-COMMERCIAL THINNING AT AGE 8 YEARS AND LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 82C5)
Diameter class
Inches
5
6
7
8
9
10
11
12
13
Total
Average
Site index'
Trees
Number
0
0
8
86
56
48
24
24
8
204
91
Dominants and codominants
Basal area Average height
Sq. feet Feet
0.0
.0
2.2
12.6
24.7
26.2
15.8
18.8
7.4
107.7
.528
71
70
73
783
75
77
84
74
Stand 3.6 in. d.b.h. and larger
Trees Basal area Average height
Number Sq. feet Feet
4 0.6 47
4 .8 62
36 9.6 66
48 16.8 68
72 31.8 72
52 28.3 74
24 15.8 75
24 18.8 77
8 7.4 84
272 129.9
.... 478 71
Based on total height of dominants and codominants.
[41]
I I r
APPENDIX TABLE B 4. STAND PER ACRE 
AT PLANTATION AGE 31 YEARS, SLASH PINE PLANTED 
AT 4' X 4' SPACING AND THINNED
TWICE-PRE-COMMERCIAL THINNING AT AGE 8 YEARS 
AND LATER COMMERCIAL THINNING AT AGE 19 
YEARS (PLOT 31B4)
Diameter class Dominants and Codominants 
Stand 3.6 in. d.b.h. and larger
Trees Basal area Average 
height Trees Basal area 
Average height
Inches Number 
Sq. feet Feet 
Number Sq. feet 
Feet
5 0 0.0 4 0.5 60
6 0 .0 
8 1.6 61
7 16 4.3 63 
20 5.3 63
8 44 15.3 
69 60 20.9 
67
9 64 28.3 
68 80 35.4 
68
10 44 24.0 
72 44 24.0 
72
11 36 23.8 
76 36 23.8 
76
12 4 3.1 
79 4 3.1 
79
13 0 .0 
0 .0
14 4 4.3 75 
4 4.3 75
Total 212 
103.1 
260 118.9
Average .486 
71 .457 
69
Site index' 88
1Based on total height of dominants 
and codominants.
APPENDIX TABLE B 5. STAND PER ACRE AT PLANTATION 
AGE 31 YEARS, SLASH PINE PLANTED AT 4' X 4' 
SPACING AND THINNED
TWICE-PRE-COMMERCIAL THINNING AT AGE 8 
YEARS AND LATER COMMERCIAL THINNING AT AGE 
19 YEARS (PLOT 31B3)
Diameter class Dominants and codominants Stand 3.6 in. d.b.h. and 
larger
Trees Basal area Average height 
Trees Basal area Average height
Inches Number Sq. 
feet Feet Number 
Sq. feet Feet
6 4 0.8 72 12 
2.4 62
7 12 3.2 65 28 
7.5 65
8 20 7.0 68 
48 16.7 68
9 84 37.1 70 100 44.2 
69
10 60 32.7 
74 60 32.7 
74
11 28 18.5 75 
28 18.5 75
Total 208 99.3 
276 122.0
Average .477 
72 .442 70
Site index' 89
Based on total height of dominants and codominants.
APPENDIX TABLE B 6. STAND PER ACRE 
AT PLANTATION AGE 31 YEARS, SLASH PINE 
PLANTED AT 4' X4' SPACING AND THINNED
TWICE-PRE-COMMERCIAL THINNING AT AGE 
8 YEARS AND LATER COMMERCIAL THINNING 
AT AGE 19 YEARS (PLOT 32C6)
Diameter class Dominants and codominants 
Stand 3.6 in. d.b.h. and larger
Trees Basal area Average height 
Trees Basal area Average height
Inches Number Sq. feet 
Feet Number Sq. feet 
Feet
5 0 0.0 
8 1.1 53
6 8 1.5 
58 40 7.8 
55
7 28 7.5 
64 56 15.0 
62
8 92 32.1 
66 100 34.9 
65
9 72 31.8 
67 72 31.8 
67
10 44 24.0 
68 44 24.0 
68
11 20 13.2 
67 20 13.2 
67
12 8 6.3 
69 8 6.3 
69
Total 272 116.4 
348 134.1
Average.. .428 
67 --. 385 
64
Site index' 82
1 Based on total height of dominants and 
codominants.
[42]
APPENDIX TABLE B 7. STAND PER ACRE AT PLANTATION 
AGE 31 YEARS, SLASH PINE PLANTED AT 6'X 6' SPACING
AND NOT THINNED (PLOT 32C13)
Diameter class
Inches
4
5
6
7
8
9
10
11
12
13
14
15
Trees
Number
4
4
36
24
80
104
64
44
4
4
4
4
Total 876
Average
Site index
1  
92
1 Based on total height of domin
Dominants and codominants
Basal area Average height
Sq. feet Feet
0.4 81
.5 73
7.1 72
6.4 72
27.9 74
46.0 75
34.9 77
29.0 76
3.1 76
3.7 74
4.3 81
4.9 80
168.2
.447 75
ants and codominants.
Stand 3.6 in. d.b.h. and larger
Trees Basal area Average 
height
Number Sq. feet Feet
52 4.5 46
72 9.8 60
80 15.7 63
52 13.9 70
100 34.9 72
120 53.0 74
68 37.1 76
44 29.0 76
4 3.1 76
4 3.7 74
4 4.3 81
4 4.9 80
604 213.9
.354 
68
APPENDIX TABLE B 8. STAND PER ACRE AT PLANTATION 
AGE 31 YEARS, SLASH PINE PLANTED AT 6' X 6' 
SPACING ON
EXCEPTIONAL SITE AND NOT THINNED (PLOT 
31A1)
Diameter class
Inches
6
7
8
9
10
11
12
13
14
15
16
17
18
Trees
Number
0
0
4
16
12
32
24
4
28
20
4
0
4
Total 148
Average
Site index' 102
SBased on total 
height of domir
Dominants and codominants
Basal area Average height
Sq. feet Feet
0.0 ..
.0
1.4 
80
7.1 78
6.5 84
21.1 83
18.9 81
3.7 85
29.9 85
24.5 84
5.6 90
.0
7.1 90
125.8
.850 83
cants and codominants.
Stand 3.6 in. d.b.h. and larger
Trees Basal area Average 
height
Number Sq. feet Feet
4 0.8 70
0 .0
12 4.2 72
40 17.7 76
28 15.2 81
32 21.1 83
28 22.0 80
4 3.7 85
28 29.9 85
20 24.5 84
4 5.6 90
0 .0
4 7.1 
90
204 151.8
.... 744 81
APPENDIX TABLE B 9. STAND PER ACRE AT PLANTATION AGE 81 YEARS, 
SLASH PINE PLANTED AT 6' X 6' SPACING AND
THINNED ONCE-LATER COMMERCIAL THINNING AT AGE 
19 YEARS (PLOT 32C1)
Diameter class Dominants and codominants 
Stand 3.6 in. d.b.h. and larger
Trees Basal area Average height 
Trees Basal area Average height
Inches Number Sq. feet 
Feet Number Sq. feet Feet
4 0 0.0 
28 2.4 31
5 0 .0 
4 .5 43
6 0 .0 
4 .8 45
7 16 4.3 
59 32 8.6 
56
8 86 12.5 
61 48 16.8 
61
9 28 12.4 
63 28 12.4 
63
10 44 24.0 
67 52 28.3 
67
11 24 15.8 
68 24 15.8 
68
12 40 31.4 
68 40 31.4 
68
Total 188 100.4 
260 117.0
Average ... .534 
65 .450 59
Site index
1  
80
1 Based on total height of dominants and codominants.
[43 1
APPENDIX TABLE B 10. STAND PER ACRE AT PLANTATION AGE 31 YEARS, SLASH PINE PLANTED AT 6' X 6' SPACING AND
THINNED ONCE-LATER COMMERCIAL THINNING AT AGE 18 YEARS (PLOT 35C3, "6'X> 6'D")
Diameter class
Inches
4
5
6
7
8
9
10
11
12
13
Trees
Number
0
0
0
12
40
56
56
24
12
4
Total 204
Average --
Site index
1  
79
1 Based on total height of domir
Dominants and codominants
Basal area Average height
Sq. feet Feet
0.0 --
.0 --
.0 --
3.2 62
14.0 61
24.8 64
30.5 66
15.8 68
9.4 66
3.7 65
101.4 --
.497 64
iants and codominants.
Stand 3.6 in. d.b.h. and larger
Trees Basal area Average height
Number Sq. feet Feet
8 0.7 38
4 .6 53
32 6.3 56
72 19.2 -59-
104 36.3 60
84 37.1 62
64 34.9 66
24 15.8 68
12 9.4 66
4 3.7 65
408 164.0 __
___.402 61
APPENDIX TABLE B 11. STAND PER ACRE AT PLANTATION AGE 31 YEARS, SLASH PINE PLANTED AT 6'X> 6' SPACING AND THINNED
TWICE-LIGHT, EARLY COMMERCIAL THINNING AT AGE 12 YEARS AND LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 31B1)
Diameter class
Inches
4
5
6
7
8
9
10
11
12
13
14
Total
Average
Dominants and codominants
Trees Basal area Average height
Number Sq. feet Feet
0 0.0 ----
0 
00 .0 
--
0 .0 _-
4 1.4 68
16 7.1 77
32 17.4 78
36 23.7 80
24 18.8 78
8 7.4 82
8 8.6 79
128 84.4 --
---. 660 78
Site index' 96
'Based on total height 
of dominants and codominants.
Stand 3.6 in. d.b.h. and larger
Trees Basal area Average height
Number Sq. feet Feet
4 0.3 29
4 .5 48
8 1.6 67
28 7.5 68
52 18.2 69
36 15.9 71
48 26.2 75
44 29.0 79
24 18.8 78
8 7.4 82
8 8.6 79
264 134.0 __
__ .507 72
APPENDIX TABLE B 12. STAND PER ACRE AT PLANTATION AGE 31 YEARS, SLASH PINE PLANTED AT 6' X 6' SPACING AND THINNED
TWICE-LIGHT, EARLY COMMERCIAL THINNING AT AGE 12 YEARS AND LATER COMMERCIAL THINNING AT AGE
19 YEARS (PLOT 31A5)
Diameter class
Inches
4
5
6
7
8
9
10
11
12
13
14
Total
Average
Site index'
Dominants and codominants
Trees
Number
0
0
0
12
32
36
56
40
24
12
8
220
85
Basal area
Sq. feet
0.0
.0
.0
3.2
11.2
15.9
30.5
26.4
18.8
11.1
8.6
125.7
.571
Average height
Feet
66
66
67
69
71
74
72
78
69
Stand 3.6 in. d.b.h. and larger
Trees Basal area Average height
Number Sq. feet Feet
8 0.7 43
20 2.7 53
28 5.5 57
28 7.5 64
40 13.9 65
48 21.2 66
56 30.5 69
40 26.4 71
24 18.8 74
12 11.1 72
8 8.6 78
312 146.9 --
.471 66
'Based on total height of dominants and codominants.
144]
I_
UVIIIIIIUIIW L~LIU ~VUVIIIILICILIC~
APPENDIX TABLE B 13. STAND PER ACRE AT PLANTATION AGE 31 YEARS, SLASH PINE PLANTED AT 6' X 6' SPACING AND
THINNED TWICE-LIGHT, EARLY COMMERCIAL THINNING AT AGE 12 YEARS AND LATER COMMERCIAL
THINNING AT AGE 19 YEARS (PLOT 32C7)
Diameter class
Inches
4
5
6
7
8
9
10
11
12
13
Total
Average
Site index
1
Dominants and codominants
Trees
Number
0
0
4
20
52
44
40
32
16
4
212
80
Basal area
Sq. feet
0.0
.0
.8
5.3
18.1
19.5
21.8
21.1
12.6
3.7
102.9
.485
Average height
Feet
59
60
62
65
66
69
72
68
65
Trees
Number
8
0
28
36
72
60
40
32
16
4
296
Stand 3.6 in. d.b.h. and larger
Basal area Average height
r Sq. feet Feet
0.7 36
5.5 
53
9.6 59
25.1 61
26.5 63
21.8 66
21.1 69
12.6 72
3.7 68
126.6
.428 62
1 Based on total height of dominants 
and codominants.
APPENDIX TABLE B 14. STAND PER ACRE AT PLANTATION AGE 31 YEARS, SLASH PINE PLANTED AT 6' X 6' SPACING AND
THINNED TWICE-LIGHT, EARLY COMMERCIAL THINNING AT AGE 12 YEARS AND LATER COMMERCIAL
THINNING AT AGE 19 YEARS (PLOT 32C2)
Diameter class
Inches
6
7
8
9
10
11
12
13
Total
Average
Site index
1
Trees
Number
0
4
24
44
48
36
28
16
200
86
Dominants and codominants
Basal area Average height
Sq. feet Feet
0.0 ---
1.1 64
8.4 65
19.4 70
26.1 68
23.8 73
22.0 76
14.7 70
115.5
.578 70
Stand 3.6 in. d.b.h. and larger
Trees Basal area Average height
Number Sq. feet Feet
4 0.8 42
8 2.1 61
32 11.2 64
44 19.4 70
52 28.4 68
36 23.8 73
28 22.0 76
16 14.7 70
220 122.4
.556 69
1 Based on total height of dominants and codominants.
APPENDIX TABLE B 15. STAND PER ACRE AT PLANTATION AGE 31 YEARS, SLASH PINE PLANTED AT 6' X 6' SPACING AND
THINNED TWICE-HEAVY, EARLY COMMERCIAL THINNING AT AGE 12 YEARS AND LATER COMMERCIAL
THINNING AT AGE 19 YEARS (PLOT 32C3)
Diameter class
Inches
8
9
10
11
12
13
14
Total
Average
Site index'
Trees
Number
0
32
16
28
24
28
8
186
90
Dominants and codominants
Basal area Average height
Sq. feet Feet
0.0
14.2 72
8.7 68
18.5 71
18.8 73
25.8 76
8.6 82
94.6
.695 73
Stand 3.6 in. d.b.h. and larger
Trees Basal area Average height
Number Sq. feet Feet
12 4.2 63
48 21.2 69
28 15.8 67
32 21.1 70
24 18.8 73
28 25.8 76
8 8.6 82
180 115.0
.... 639 70
1 Based on total height of dominants and codominants.
[ 45]
Dominants 
and 
codominants
APPENDIX TABLE B 16. STAND PER ACRE AT PLANTATION AGE 81 YEARS, SLASH PINE PLANTED AT 6' X 6' SPACING AND
THINNED TWICE-HEAVY, EARLY COMMERCIAL THINNING AT AGE 12 YEARS AND LATER COMMERCIAL
THINNING AT AGE 19 YEARS (PLOT 31B5)
Diameter class
Inches
7
8
9
10
11
12
13
Trees
Number
0
48
56
32
32
44
16
Total 228
Average
Site index' 88
Based on total height of domin
Dominants and codominants
Basal area Average height
Sq. feet Feet
0.0
16.8 67
24.8 71
17.4 69
21.1 72
34.5 73
14.8 77
129.4
.567 71
iants and codominants.
Stand 3.6 in. d.b.h. and larger
Trees Basal area Average height
Number Sq. feet Feet
8 2.1 62
52 18.2 67
56 24.8 71-
32 17.4 69
32 21.1 72
44 84.5 73
16 14.8 77
240 132.9
.... 554 70
APPENDIX TABLE B 17. STAND PER ACRE AT PLANTATION AGE 81 YEARS, SLASH PINE PLANTED AT 6' X 6' SPACING AND
THINNED TWICE-HEAVY, EARLY COMMERCIAL THINNING AT AGE 12 YEARS AND LATER COMMERCIAL
THINNING AT AGE 19 YEARS (PLOT 81B2)
Trees
Number
0
4
28
52
60
32
4
8
Dominants and codominants
Basal area Average height
Sq. feet Feet
0.0
1.4 69
12.4 70
28.3 72
39.6 74
25.1 75
3.7 74
8.6 76
Total 188 119.1
Average . .6383
Site index' 90
1 Based on total height of dominants and codominants.
73
Trees
Number
4
12
40
56
60
32
4
8
216
Stand 3.6 in. d.b.h. and larger
Basal area Average height
r Sq. feet Feet
1.0 65
4.2 66
17.7 71
30.5 71
39.6 74
25.1 75
8.7 74
8.6 76
180.4
.604 72
APPENDIX TABLE B 18. STAND PER ACRE AT PLANTATION AGE 31 YEARS, SLASH PINE PLANTED AT 6' X 8' SPACING AND
THINNED TWICE-LIGHT, EARLY COMMERCIAL THINNING AT AGE 14 YEARS AND LATER COMMERCIAL
THINNING AT AGE 18 YEARS (PLOT 35A7)
Diameter class
Inches
6
7
8
9
10
11
12
13
14
Dominants and codominants
Trees
Number
0
0
32
68
72
20
16
0
4
Basal area
Sq. feet
0.0
.0
11.2
30.0
39.2
13.2
12.6
.0
4.3
Total 212 110.5
Average .521
Site index
1  
80
1 Based on total height of dominants and codominants.
Stand 3.6 in. d.b.h. and larger
Average height
Feet
62
68
66
69
71
75
65
Trees
Number
20
20
60
84
76
24
16
0
4
304
Basal area
Sq. feet
3.9
5.3
20.9
37.1
41.5
15.8
12.6
.0
4.3
141.4
.465
Average height
Feet
53
55
61
63
65
69
71
75
63
[ 46J]
Diameter class
Inches
7
8
9
10
11
12
13
14
APPENDIX TABLE B 19. STAND PER ACRE AT PLANTATION AGE 31 YEARS, SLASH PINE PLANTED AT 6' X 8' SPACING AND
THINNED TWICE-HEAVY, EARLY COMMERCIAL THINNING AT AGE 14 YEARS AND LATER COMMERCIAL
THINNING AT AGE 18 YEARS (PLOT 35B7 )
Diameter class
Inches
4
5
6
7
8
9
10
11
12
13
Total
Average
Site index'
Trees
Number
0
0
0
4
4
40
40
44
24
4
160
77
Dominants and codominants
Basal area Average height
S q. feet Feet
0.0
.0
.0
1.1
1.4
17.7
21.8
29.0
18.8
3.7
93.5
.584
56
55
62
61
67
67
62
63
Stand 3.6 in. d.b.h. and larger
Trees
Number
8
0
4
16
28
48
44
44
24
4
220
Basal area Average height
Sq. feet Feet
0.7
.0
.8
4.3
9.8
21.2
24.0
29.0
18.8
3.7
112.3
.510
30
48
54
57
61
61
67
67
62
60
1 Based on total height of dominants and codominants.
APPENDIX TABLE B 20. STAND PEE ACRE .AT PLANTATION AGE 31 YEARS, SLASH PINE PLANTED AT 8' X 8' SPACING AND THINNED
ONCE-LATER COMMERCIAL THINNING AT ACE 19 YEARS (PLOT 32C9)
Diameter class
Inches
5
6
7
8
9
10
11
12
13
Total
Average
Site index'
Dominants and codominants
Trees
Number
4
0
20
24
68
40
4
20
4
184
77
Basal area Average height
Sq. feet Feet
0.5 54
.0
5.3
8.4
30.1
21.8
2.6
15.7
3.7
88.1
.479
59
58
65
64
64
68
68
63
Trees
Number
20
20
32
40
68
40
4
20
4
248
Stand 3.6 in. d.b.h. and larger
Basal area Avei
Sq. feet
2.7
3.9
8.5
14.0
30.1
21.8
2.6
15.7
3.7
103.0
.415
'Based on total height of dominants and codominants.
APPENDIX TABLE B 21. STAND PER ACRE AT PLANTATION AGE 31 YEARS, SLASH PINE PLANTED AT 8' X 8' SPACING AND THINNED
ONCE-LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 32C8
Diameter class
Inches
5
6
7
8
9
10
11
12
Total
Average
Site index'
Dominants and codominants
Trees
Number
0
4
12
32
64
40
20
4
176
80
Basal area Average height
Sq. feet Feet
0.0
.8
3.2
11.2
28.3
21.8
13.2
3.1
81.6
.464
59
64
63
66
66
70
67
66
Trees
Number
8
16
24
44
64
40
24
4
224
Stand 3.6 in. d.b.h. and larger
Basal area Average height
Sq. feet Feet
1.1 52
3.1 57
6.4 60
15.4 61
28.3 66
21.8 66
15.9 69
3.1 67
95.1
.424 64
1 Based on total height of dominants and codominants.
[47]
;rage height
Feet
45
53
58
58
65
64
64
68
68
61
APPENDIX TABLE B 22. STAND PER ACRE AT PLANTATION AGE 31 YEARS, SLASH PINE PLANTED AT 8' X 8' SPACING AND THINNED
ONCE-LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 31A4)
Dominants and codominants
Average height
Feet
64
72
70
72
76
78
72
Stand 3.6 in. d.b.h. and larger
Trees Basal area Average height
Number Sq. feet Feet
12 1.6 55
12 2.3 58
4 1.1 68
20 7.0 64
28 12.4 72
48 26.2 70
48 31.7 72
20 15.7 76
20 18.4 78
212 116.4
.549 70
1 Based on total height of dominants and 
codominants.
APPENDIX TABLE B 23. STAND PER ACRE AT PLANTATION AGE 31 YEARS, SLASH PINE PLANTED AT 8' X 8' SPACING AND
THINNED TWICE-LIGHT, EARLY COMMERCIAL THINNING AT AGE 15 YEARS AND LATER COMMERCIAL
THINNING AT AGE 19 YEARS (PLOT 31B6)
Diameter class Dominants and codominants
Trees Basal area Average height
Inches Number Sq. feet Feet
5
6
7
8
9
10
11
12
13
14
15
0
0
0
28
24
56
36
32
20
0
4
0.0
.0
.0
9.8
10.6
30.5
23.8
25.1
18.4
.0
4.9
Total 200 123.1
Average .616
Site index' 88
1 Based on total height of dominants and codominants.
67
70
68
71
75
77
78
71
Trees
Number
4
4
8
44
24
56
36
32
20
0
4
232
Stand 3.6 in. d.b.h. and larger
Basal area Average height
r Sq. feet Feet
0.6 55
.8 61
2.1 57
15.4 65
10.6 70
30.5 68
23.8 71
25.1 75
18.4 77
.0
4.9 78
132.2
.570 69
APPENDIX TABLE B 24. STAND PER ACRE AT PLANTATION AGE 31 YEARS, SLASH PINE PLANTED AT 91/' X 91/2' SPACING AND
THINNED ONCE-LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 31B7)
Diameter class
Inches
6
7
8
9
10
11
12
13
14
15
16
Total
Average
Site index'
Dominants and codominants
Trees
Number
0
0
16
20
28
48
52
4
4
0
4
176
88
Basal area
Sq. feet
0.0
.0
5.6
8.8
15.2
31.7
40.8
3.7
4.3
.0
5.6
115.7
.658
Average height
Feet
64
67
71
70
73
79
75
82
71
Stand 3.6 in. d.b.h. and larger
Trees Basal area Average height
Number Sq. feet Feet
12 2.4 59
8 2.1 57
32 11.2 62
24 10.6 65
32 17.4 70
48 31.7 70
52 40.8 73
4 3.7 79
4 4.3 75
0 .0
4 5.6 82
220 129.8
..... 590 69
SBased on total height of dominants 
and codominants.
[48]
Diameter class
Inches
5
6
7
8
9
10
11
12
13
Total
Average
Site index'
Trees
Number
0
0
12
28
48
44
20
20
172
89
Basal area
Sq. feet
0.0
.0
.0
4.2
12.4
26.2
29.0
15.7
18.4
105.9
.616
'Iiui .rr
Dominants 
and 
codominants
vv
APPENDIX TABLE B 25. STAND PER ACRE AT PLANTATION AGE 31 YEARS, SLASH PINE PLANTED AT 91/-2' X 91/' SPACING AND
THINNED ONCE-LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 32C10)
Diameter class
Inches
4
5
6
7
8
9
10
11
12
13
14
Total
Average
Site index'
1
Trees
Number
0
0
0
0
16
24
40
36
24
24
4
168
84
Dominants and codominants
Basal area Av
Sq. feet
0.0
.0
.0
.0
5.6
10.6
21.8
23.8
18.8
22.1
4.3
107.0
.637
erage height
Feet
63
64
67
72
70
72
74
69
Trees
Number
4
0
0
4
28
40
44
36
24
24
4
208
Stand 3.6 in. d.b.h. and larger
Basal area Average height
Sq. feet Feet
0.3 29
.0--
.0
1.1 52
9.8 61
17.7 64
24.0 67
23.8 72
18.8 70
22.1 72
4.3 74
121.9
.586 67
1 Based on total height 
of dominants and codominants.
APPENDIX TABLE B 26. STAND PER ACRE AT PLANTATION AGE 81 YEARS, SLASH PINE PLANTED AT 12'X 12' SPACING AND THINNED
ONCE-LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 82C011)
Diameter class
Inches
8
9
10
11
12
13
14
15
Total
Average
Site index'
Trees
Number
8
8
16
20
12
24
8
8
104
90
Dominants and codominants
Basal area Average height
Sq. feet Feet
2.8 70
3.5 72
8.7 783
13.2 70
9.4 73
22.1 75
8.6 73
9.8 76
78.1
.752 73
Stand 3.6 in. d.b.h. and larger
Trees Basal area Average height
Number Sq. feet Feet
8 2.8 70
16 7.1 66
16 8.7 73
24 15.8 68
16 12.6 70
32 29.5 73
8 8.6 78
8 9.8 76
128 94.9
.. 741 71
' Based on total height of dominants and codominants.
APPENDIX TABLE B 27. STAND PER ACRE AT PLANTATION AGE 81 YEARS, SLASH PINE PLANTED AT 12' X 12' SPACING AND THINNED
ONCE-LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 31A2)
Diameter class
Inches
6
7
8
9
10
11
12
13
14
15
Trees
Number
0
0
4
4
24
12
20
82
8
12
Total 116
Average ..
Dominants and codominants
Basal area Average height
Sq. feet Feet
0.0
.0
1.4 74
1.8 79
13.1 76
7.9 81
15.7 85
29.5 82
8.6 79
14.7 83
92.7___
.878 81
Site index' 100
1Based on total height of dominants and codominants.
Trees
Number
4
0
4
8
24
12
24
32
8
12
128
Stand 3.6 in. d.b.h. and larger
Basal area Average height
r Sq. feet Feet
0.8 60
.0
1.4 74
3.5 75
13.1 76
7.9 81
18.8 84
29.5 82
8.6 79
14.7 83
98.8
.787 80
[49 ]
E
APPENDIX TABLE B 28. STAND PER ACRE AT PLANTATION AGE 31 YEARS, SLASH 
PINE PLANTED AT 16' X 16' SPACING AND THINNED
ONCE-LATER COMMERCIAL THINNING AT AGE 19' YEARS (PLOT 32C12)
Diameter class Dominants and codominants Stand 3.6 in. d.b.h. and 
larger
Trees Basal area Average height Trees Basal area Average 
height
Inches Number Sq. feet Feet Number Sq. feet 
Feet
10
11
12
13
14
15
16
0
8
28
16
12
12
12
0.0
5.3
22.0
14.8
12.8
14.7
16.7
Total 88 86.3
Average .. 981
Site index
1  
94
1 Based on total height of dominants and codominants.
77
73
75
78
79
77
76
12
8
28
16
12
12
12
100
6.6 67
5.3 77
22.0 73
14.8 .75
12.8 78
14.7 79
16.7 77
92.9
.929 75
APPENDIX TABLE B 29. STAND PER ACRE AT PLANTATION AGE 81 YEARS, SLASH PINE PLANTED AT 16' X 16' SPACING AND THINNED
ONCE-LATER COMMERCIAL THINNING AT AGE 19 YEARS (PLOT 31A6)
Diameter class
Inches
4
5
6
7
8
9
10
11
12
13
14
15
Total
Average
Site index'
Trees
Number
0
0
0
0
0
0
8
12
16
12
24
16
88
95
Dominants and codominants
Basal area Average height
Sq. feet Feet
0.0
.0
.0
.0
.0
.0
4.4
7.9
12.6
11.1
25.6
19.6
81.2
.923
72
72
74
79
78
82
77
Trees
Number
4
0
0
0
4
0
8
16
16
12
24
16
100
Stand 3.6 in. d.b.h. and larger
Basal area Average height
Sq. feet Feet
0.3 44
.0--
.0
.0.
1.4 68
.0
4.4 72
10.6 70
12.6 74
11.1 79
25.6 78
19.6 82
85.6
.856 74
SBased on total height of dominants and codominants.
APPENDIX TABLE B 30. STAND PER ACRE AT PLANTATION AGE 1 YEARS, SLASH PINE PLANTED AT 19' X 19' SPACING
AND NOT THINNED (PLOT 81A7)
Diameter class
Inches
8
9
10
11
12
13
14
15
16
17
18
Total
Average
Site index'
Dominants and codominants
Trees
Number
0
0
4
8
8
12
8
4
8
0
4
56
90
Basal area
Sq. feet
0.0
.0
2.2
5.3
6.3
11.0
8.5
4.9
11.2
.0
7.1
56.5
1.009
Average height
Feet
68
67
70
73
75
73
80
82
783
Trees
Number
12
0
4
8
8
12
8
4
8
0
4
68
Stand 3.6 in. d.b.h. and larger
Basal area Average height
Sq. feet Feet
4.2 61
.0
2.2 68
5.3 67
6.3 70
11.0 73
8.5 75
4.9 73
11.2 80
.0
7.1 82
60.7
.892 71
SBased on total height of dominants and codominants.
[ 50]
al~a II
I~