a,
'V
A k
p
rod
a
A Word With The Editor
T ODAY'S SUCCESS-ORIENTED farmer
or other businessman likes to cut through
detailed analyses and get to what is com-
monly known as the "bottom 
line." After all,
that bottom line is the final measure of success,
representing the profit made in a business or
farming venture or the return from an investment.
This same bottom-line accounting system is ap-
propriate for evaluating research programs at
state agricultural experiment stations. Large sums
are spent on U.S. agricultural research, so it is
important to know what Americans are getting R.E. STEVENSON
in return.
We're regularly told that money spent on agricultural research is an inxest-
ment that pays big dividends, but it has been difficult to document this payoff.
Now there is reliable information from research to accurately measure the tate
of return. These national studies computed dollar returns from research in
regard to the national economy, the efficiency of agricultural enterprises, and
advantages to consumers. In every case, returns far exceed what might be ex
pected from investments in other areas of the U.S. economy.
Such research advances as superior crops, farm mechanization, genetic and
nutritional break-throughs in meat animals, and effective insect and disease
control systems are universally recognized. But these are just the tip of the
iceberg. A summary o 21 studies dealing vith different crop and livestock
enterprises indicates returns of 30-100 percent annually from long-term
research. Technology-oriented research in the South from the mid-1940's un-
til the 1970's was reported to return at the rate of 130 percent annually.
The secondary or multiplier effect on income and employment has received
less attention, but a Virginia study showed that adding $1 million for public
agricultural research adds about $9 million to agricultural output. Further-
more, this $1 million investment adds almost $11 million to the gross state
product and more than 300 man-years of employment. Based on this same
multiplier effect, Alabama's $26 million expenditure on agricultural research
adds: (1) $234 million to the State's agricultural output; (2) $286 million to
the gross state product; and (3) 7,800 man-years of employment.
Other data established the payoff to the consuming public. Taxes paid per
family to support U.S. agricultural research vere reported to average $14.38
per year. For each $1.00, there was an average return of $2.68. Low-income
families received the greatest return, $11.60 for each $1.00 they paid in taxes
to support research.
Future payoffs should be even greater as research utilizes genetic engineer-
ing and other high-tech research methods. The bottom line should be high
quality agricultural products at even lower consumer costs, along vith a clean
environment to be enjoyed by all.
SPRING 1988 VOL. 35, No. I
A quarterly report of iesearch published
by the Alabama Agrieuliura Experiment
Station, Auburn University.
LOWELL T. EROBISH ...... Director
DAVID H. TEEM ... Assistant Directoi
R.E. STEVENSON ............ Editor
ROY ROBERSON ... Associate Editor
KATIE SMITH ....... Assistant Editor
TERESA RODRIGUEZ .. Art Designer
Editorial Committee: Iowell T. Erobish;
P. A. Duf fy, A ssisitan Prole sor 01A ri-
cltural LEonomiics ((d Rioral Socio/og i
R.I. LovelI, Professor of 1-isleries and
A/lied Aquacultuires; T. P. Mack, Asso-)
c/aLe Professor o1 Entiomologyv; G.J.
Keever, A ssociae Professor of Horti-
cuiture; R.E. Keith, Associate Professor
of Nu uionl and I oods; A.I. 
Iatham,
Associate Professor of P/ant Pathology
.IA. Renden, 1Associate Pro/essor of
Poultrv Sciene; D.1. South, A ssant
Professor of/ orestri'; tD.A. Stringfllow,
Assistant a Professor of Microbiology; and
R.E. Stevenson.
MAY WE INTRODUCE
Dr. Graeme
I ockaby, Asso-
ciate Professor of
IFoiestrv. A native
of Seneca, Southr
C arolina, L ockaby
iame to Auburn in
i986 from Iouis-
iana Tech Univer-
sity, sheire he held a teaching and research
appointment in forestry.
ILockabs eained his B.S. and M.S. degrees
in forestry from Clemson Universits and his
Ph.D. in agronoms from Mississippi State
Uniersisit. While at Clemson. he served as
a graduate research assistant in forestiy and
feld a siiila position in agionoms at Nliss-
issippi State.
One of his firs assignments at Auburn v as
to help initiate an air pollution studs to deter-
niiiie the effect s of acid rain and other con-
taminants on the grov th rate of pine trees.
He is also studying the ielationship of
cenetics and nutrition in pine trees and is
workiig on a joint project vith researchers
in w ildlife to study forest practices that could
impiove vw ildlife Ihabitat and increase forest
land huntinc lease values in Alabama. Some
of I ockabys work on the factos influenc-
ing pine productivits is ieported on pace 3
of this issue of Highilighs.
ON THE COVER. Broadleaf weed control in
strawberries, like these at the Chilton Area
Horticulture Substation, is a major problem
for Alabama growers, because of a lack of
herbicides registered for use on berries. See
related story on page 4.
EDITOR'S NOTE: Mention of trade
names does not indicate endorsement by
the Alabama Agricultural Experiment Sta-
tion of one biand over another. Any use
of pesticide rates in excess of labeled
amounts in research repoted does not
constitute recommendation of such tate.
Such use is simply part ot the scientific in-
vestigation necessary to evaluate various
materials. No chemical should be used at
rates above those permitted by the label.
In formation contained herein is asailable
to all vithout regard to iace, coloi, sex.
or national origin.
\ I'I
VARIATION in forest productivity
occurs with large changes in lati-
tude and longitude. Much of this
variation may be attributed to climatic
patterns, particularly those associated
with precipitation, temperature, and
growing season length. Although con-
siderable variation occurs, world forest
productivity generally increases from
north to south (as latitude decreases). The
same generalization has been made for the
United States and appears to be true for
pines in the Eastern United States.
While knowledge of world patterns of
potential productivity has considerable
value, an understanding of productivity
patterns for single species is also impor-
tant to understand ecological processes
and how they affect growth and to pro-
vide new management considerations.
However, the first step is to identify any
productivity patterns, which was the ob-
jective of a recent Alabama Agricultural
Experiment Station study on loblolly
pines in the State.
Site index at 50 years (the height
specified trees are expected to grow in a
set number of years), based on field mea-
surements by the USDA Soil Conserva-
tion Service, was used as the indicator for
site productivity. Field data obtained
from the Soil Conservation Service con-
sisted of 461 site index estimates for natur-
ally reproduced loblolly pine stands
Alabama Agricultural Experiment Station
distributed across Alabama. These field
estimates are based on height and age
measurements from 5-10 codominant
loblolly pines per plot and were taken in
conjunction with soil series identification
and descriptions on the same plots. Ap-
proximate plot locations, in terms of
latitude and longitude, were also ob-
tained.
A comparison across all soils of site in-
dices versus latitude revealed the presence
of considerable variation. However, site
index values tended to increase as latitude
decreased until an inflection point was
reached just north of 32 
? 
latitude. Site in-
dices then decreased south of this point,
as the Gulf Coast was approached, figure
1. The range of site index values
associated with this pattern was approx-
imately 60-105 ft. No relationship was ap-
parent for site index versus longitude.
In an effort to reduce the soil variation
associated with the observed pattern, data
associated with Typic Hapludult soils were
separated and compared with latitude.
Typic Hapludults were chosen because a
much larger subset was associated with
this subgroup designation than any other.
This subgroup accounts for numerous
soils in the Appalachian Plateau, Pied-
mont Plateau, Coastal Plains, and Flood
Plains and Terraces areas of Alabama.
Included are the series Albertville, Ap-
pling, Cahaba, Cecil, Cheaha, Enders,
FIG. 1 (left). Relationship between loblolly
pine site index and latitutde.
FIG. 2 (right). Relationship between loblolly
pine site index and latitude for Typic
Hapludults with siliceous mineralogy.
Grover, Hartsells, Linker, Luverne, Mad-
ison, McQueen, Tatum, and Townley.
Figure 2 reveals the relationship be-
tween site index and latitude for Typic
Hapludults with siliceous mineralogy. A
similar pattern to that described in figure
1 is seen as site indices increase with
decreasing latitude until maximized just
north of 32
? 
latitude and decrease
thereafter. However, no pattern was ap-
parent for site index versus longitude for
any Typic Hapludult subset.
The identification of this gradient will
help define interactions of growth factors
that control loblolly pine productivity.
Several implications for management also
are generated by the existence of this
gradient. Spatial patterns in the natural
productivity of the species may indicate
the need for adjustments of silvicultural
prescriptions to fit the gradient. Similarly,
the element of risk in forestry investments
may be shown to be influenced by the
pattern.
Lockaby is Associate Professor and Caulfield is
Assistant Professor of Forestry.
A.W. Caylor, W.A. Dozier, Jr., G.R. Wehtje, and J.A. Pitts
LACK OF registered broadleaf
herbicide compounds for straw-
berries makes broadleaf weed
control a difficult problem for strawberry
producers. Most of the herbicides now
available for use in strawberry production
are restricted in use and in effectiveness.
For example, Tenoran , the most com-
monly used herbicide for broadleaf weed
control in the Southeast, generally exhibits
poor control when used'alone. Other her-
bicides, such as Sinbar 
, Princep , 2,
4-DB, and Paraquat?, are limited by such
factors as soil composition, plant matur-
ity, and growing seasons.
Research at the Alabama Agricultural
Experiment Station may help expand
herbicide choices for strawberry pro-
ducers. At the Chilton Area Horticulture
Substation, various herbicides were
evaluated using them with and without
Tenoran. All herbicide treatments con-
tained a non-ionic surfactant at the rate
of 1% by volume. Herbicide treatments
were evaluated for their effect on percent
broadleaf weed and grass control, percent
strawberry foliar injury, runner mortal-
ity, and yield.
Dormant Delite strawberry plants were
placed in a Ruston fine sandy loam dur-
ing the fall of 1985. Plants were spaced
12 in. apart in 42-in. rows and allowed
to form a matted row. Plantings were drip
irrigated using biwall tubing. Recom-
mended cultural practices for fertility and
insect and disease control were followed.
Natural weeds present in the plots in-
cluded common 
purslane, Florida 
pusley,
carpet weed, spiny pigweed, large
crabgrass, and goosegrass. All plots were
overseeded with sicklepod, 
coffee senna,
morningglory species, and prickly sida
following renovation of the planting in
June.
Tenoran was applied pre-emergence
following renovation. Diphenyl ether
herbicides (Blazer?, Cobra?, and
Reflex?) and 2, 4-DB were applied when
70% to 80%o of the broadleaf weeds were
in the dicotyledon to three-leaf stages.
Weed-free plots were hand-weeded as
needed to control broadleaf weeds and
grasses.
As shown in the table, all diphenyl
ether herbicide treatments resulted in ex-
cellent control of broadleaf weeds, con-
siderably better than 2,4-DB treatments.
The addition of Tenoran to the
postemergence herbicide treatments in-
creased broadleaf weed control.
The only weed not effectively control-
led by treatments was sicklepod. The first
flush of sicklepod germination was killed
by the diphenyl ether and 2,4-DB treat-
ments. However, second and third flushes
of sicklepod germination were not con-
trolled by any of the 
herbicide treatments,
even with the addition of Tenoran.
Blazer, Cobra, and Reflex treatments
resulted in good control of some annual
grasses in strawberries. Crabgrass and
goosegrass in the seedling stage were killed
by these treatments. Mature crabgrass and
goosegrass were stunted by the three herb-
icides, but the grasses outgrew this
damage in 2 to 3 weeks. The treatments
were able to control annual grasses for up
to 6 weeks, and their use in conjunction
with Tenoran increased annual 
grass
control.
Plants treated with Blazer, Cobra, and
Treatment,
lb./acre
Reflex experienced some slight foliar tox-
icity to the foliage present at the time of
application. This injury was characterized
by chlorosis and necrotic spotting on the
foliage; however, plants outgrew it within
3 weeks.
All diphenyl ether treatments caused in-
jury to runners present when applications
were made. Cobra and Reflex caused the
highest levels (20% to 25%o) of runner
mortality. Blazer resulted in the lowest
rate (15%). These injuries also were
characterized by chlorosis and necrotic
spotting. Immature runners were killed by
the treatments but mature runners out-
grew the damage in about 3 weeks. Plants
treated with the diphenyl ether herbicides
alone developed the highest number of
runners, while plants treated with Cobra
and Reflex combined with Tenoran
developed the fewest runners.
Strawberry yields were not adversely
affected by the diphenyl ether or 2,4-DB
treatments when compared to yields from
the hand-weeded and Tenoran-only plots.
Highest yields and best weed control were
achieved when Tenoran was applied in
conjunction with the diphenyl ether or
2-4-DB herbicides.
Caylor is a Research Specialist and Dozier is Pro-
fessor of Horticulture, Wehtje is Associate Professor
of Agronomy and Soils, and Pitts is Superintendent
of the Chilton Area Horticulture Substation.
Broadleaf Runners/
weed control 
sq. yd.
Tenoran, 4.0 ......................................
Blazer, 0.5 ........................................ ...
Cobra, 0.25 ............................................
R eflex , 0 .25 ............................................
2,4-DB, 0.25 ............... .............. .........
Tenoran & Blazer, 4 + 0.5 ................................
Tenoran & Cobra, 4 + 0.25 ...............................
Tenoran & Reflex, 4 + 0.25 .............................
Tenoran & 2,4-DB, 4+ 0.25 .................. ...........
Control/hand-weeded ...................................
Pct. No.
62 47
89 47
89 40
91 47
82 46
96 48
93 36
94 29
86 53
100 54
*Blazer, Cobra, and Reflex are not registered for use on strawberries.
Yield/
acre
Qt.
24,903
32,509
27,816
23,415
28,862
27,978
32,015
31,167
27,472
29,774
Alabama Agricultural Experiment Station
EFFECT OF POSIE ME RGENCE HERBICIDES* 
ON BROADLEAt WEED CONTROL,
RUNNER DEVE)I OPMENT, AND YIEILD OF DELIIL STRAWBERRIES
SINCE REGISTRATION of dino-
seb-containing herbicides for use
on peanuts was cancelled by the
U.S. Environmental Protection Agency
in October 1986, the Alabama Agricul-
tural Experiment Station has accelerated
testing of several herbicide alternatives.
While no herbicide offers activity iden-
tical to dinoseb, some of the replace-
ments proved to be superior in some
respects.
Though Gramoxone' has received
the most interest as a dinoseb replace-
ment, it was not included in this
research. This study was intended to
focus on herbicides that have received
less attention.
Sicklepod control with treatments 1
and 2, see table, was variable and did
not exceed 680o with any treatment or
year. Florida beggarweed control was
also variable. These two treatments pro-
vided good to excellent beggarweed con-
trol, with Lasso? being slightly superior
in 1986. The next year Dual' provided
92Wo control and Lasso only 540. This
performance demonstrates the unpre-
dictable weed control from these treat-
ments. Peanut yields from these treat-
ments were superior to the untreated
check.
All treatments with Amiben' (3-6 in
table) provided at least 8507o control of
Florida beggarweed. 
In contrast,
sicklepod control with Amiben alone
never exceeded 3507o. The addition of
Dyanap increased control, but the
amount of improvement was variable.
The best treatment was Amiben (2.0 lb.
per acre) plus Dyanap (4.5 lb. per acre),
which provided 55% and 88% control
of sicklepod for the 2 years, respective-
ly. This treatment also resulted in the
maximum yield among the Amiben-
based treatments.
The next series of treatments (7-11 in
the table) utilized Cobra' , and since no
Dyanap was included, it is meaningful
to compare performance from these
treatments to that of the standard. The
total amount of Cobra applied was 0.4
lb. per acre, and with the exception of
the last treatment in the series, control
of Florida beggarweed was in the good
to excellent category. Sicklepod control
was not as good, nor was it as consis-
tent. The best control was from Lasso
plus Cobra applied at ground cracking
with a sequential application of Cobra.
This treatment also provided the highest
yield in this series.
Alabama Agricultural Experiment Station
The next series of treatments (12-15
in the table) utilized Tough' (pyridate)
and Tough plus 2,4-DB as a supplement
to the traditional cracking time applica-
tions. Tough was initially targeted for
use in peanuts as a supplement, but it
is now being considered as a replace-
ment for dinoseb-containing herbicides.
Tough is extremely active against Florida
beggarweed (at least 98010 control from
any Tough-containing treatment). In
subsequent tests, this degree of control
has been observed apart from the use of
either Lasso or Dyanap. Tough offers
some sicklepod control, and this control
was consistently enhanced by the addi-
tion of 2,4-DB. But since Dyanap had
been used, further tests are needed to
determine if Tough can be relied upon
as a sole source of sicklepod control.
The highest yield in both years was pro-
vided by Tough-containing 
herbicides,
demonstrating the herbicide's excellent
crop safety.
The final two herbicidal treatments
(16 and 17 in the table) featured
Zorial' alone and in combination with
Lasso. While Zorial alone provided
variable control of Florida beggarweed
(990o and 6101o for the 2 years, respec-
tively), control was consistently 9907o
with the addition of Lasso. Zorial alone
provided poor control of sicklepod.
Control was markedly improved with
Lasso. Yields were intermediate between
the best treatments and the nontreated
control.
Vehtje is Associate Professor and Wilcut is a
Former Research Associate of Agronomy and
Soils.
PERFORMANCE OF VARIOUS HERBICIDE TREATMENTS FOR WEED CONTROL IN PEANUTS,
WIRFURASS SUBSTATION, 1986-87
Weed control Peanut
Treatment, lb./active acre Sicklepod Florida yield/acre
1986 1987 beggarweed 1986 1987
1986 1987
1. Dual (PPI), 2.0; Dual + 
Dyanap (CR),
2.0+ 4.5 ................................... 55' 30 87 92 3,521 2,468
2. Lasso (PPI), 2.0; Lasso + Dyanap (CR),
2.0 + 4.5 .................................. 68 31 99 54 3,075 2.868
3. Amiben DS (CR), 1.8 ........................ 21 36 99 92 3,220 2,061
4. Amiben DS + Dyanap (CR), 1.8 + 3.0........ 28 41 99 92 3,231 1.742
5. Amibcn (CR), 2.0 ......................... 34 27 90 91 3,111 1,815
6. Ai Dvanaip (CR), 2.0 14.5 ...... 88 99 85 3,526 2,214
7. Lasso + (obra (CR), 3.0 + 0.4.............. 76 0 97 100 3,568 2,069
8. Lasso + Cobra (LTCR), 3.0 + 0.4............ 64 0 95 92 3,532 1,343
9. 1Lasso (PRE); Cobra (EPOT), 3.0 ? 0.4....... 86 24 95 92 3,412 1,924
10. Lasso + Cobra (CR), 3.0 + 0.2; Cobra
(EPOT), 0.2...............................91 64 99 88 3,884 3,013
11. Iasso + Cobra (CR), 3.0 - 0.2; Cobra
(EPOT/7 day seq.), 0.1 + 0.1................ 55 0 78 0 3,412 2,868
12. Lasso +l) yanap (CR), 3.0 +4.5; Totgh
(EPOT-seq.), 0.9375 ......................... 90 14 100 100 3,26' 2,795
13. Lasso + Dyanap (CR), 3.0 + 4.5; Tough +
2,4-DB (EPOT-seq.), 0.9375 + 0.2............ 99 66 100 100 4,211 3,703
14. Lasso + Dyanap (CR), 2.0 + 4.5; Tough
(EPOT-seq.), 0.9375 ........... 84 32 98 100 3,438 3,521
15. Lasso + Dyanap (CR), 2.0 + 4.5; Tougb +
2,4-DB (EPOT-seq.), 0.9375 + 0.2 ........... 100 79 100 98 3,510 3,340
16. Zorial + Lasso (PRE), 1.5 + 3.0 ........... 96 69 99 100 2,987 2,940
17. Zorial (PRE), 1.5 ............................ 52 22 99 61 3,147 2,178
18. Nontreated-weedy ............ 0 0 0 0 2,904 1,742
Vi ccJd s cw harvested and weighed and percentage control for each herbicide treatment 
is a
comparison in weed weight to the nontreated plots.
~eanut Weed Control
Af r i"-. ;
G.R. Wehtje and J.W. WilCut
Small Towable
Center Pivot
Systems Offer
Economical
Irrigation
E.W. Rochester,
L.U. Hatch, and
J.M. Gillespie
HE LARGER the better is the
general rule for reducing initial
per acre costs of center pivot
irrigation systems. But what about
smaller fields or fields with irregular
shapes where large systems just won't
fit? Research at the Alabama Agricul-
tural Experiment Station indicates that
a small towable center pivot system may
be the answer. Although more labor was
involved, towing a system to several
points effectively reduced the cost per
acre of the system.
To evaluate the potential of towable
pivots for Alabama farmers, a two-
tower, 13-acre towable center pivot ir-
rigation system was set up at the E.V.
Smith Research Center. The pivot was
to be moved over five pivot points to
provide measurements for the required
engineering and economic analyses.
These results were then extended to
evaluate three- and four-tower systems.
Thus, the study was applicable to ir-
rigated fields from 13 to 220 acres.
A key feature of the procedure was to
irrigate a full circle in less than 24 hours
so that the system would be towed once
per day and at the same time each day.
An automatic shutdown allowed the
system to stop unattended, usually dur-
iAg the night. The next morning, the
electric motor-driven system was moved
at its highest speed to provide alignment
for towing along the prepared travel
lanes. Two men made the system ready
for towing by rotating wheels and
unhooking pipes. The system was towed
to the next pivot point where it was set
up and irrigation was then begun.
Some of the layout configurations are
shown in figure 1. The straight parallel
lines represent prepared travel lanes that
were left out of production since a tall
crop, corn, was being grown. The lanes
were 21.5 ft. wide and represented up to
3.6% of the field area, depending on the
particular configuration.
Economics was the major interest, so
the engineering designs and budgets
were based on minimum cost pro-
cedures. For example, it was assumed
that an established water supply and
three-phase power were adjacent to the
field and no pumping lift was required
except for that required by the center
pivot.
Some of the other system features in-
cluded a centrifugal pump and three-
phase electric motor with a buried pvc
pipe distribution system. Power was
provided to the center pivot with buried
electrical wires along with a kill wire to
automatically shut down the pump.
FIG. 1 (left). Lane layouts with different con-
figurations and positions.
FIG. 2 (below). Effect of irrigated area on
yearly costs.
Cost/acre
$300
$250
$200
$150
$100
$50 -
I I I I 
I I I
0 25 50 75 100 125 150 175 200 225
Irrigated area, acres
Component costs were obtained from a
local farm equipment dealer and annual
interest and insurance were assumed to
be 9.7% of the average investment.
Pumping costs were based on seven
1.5-in. applications.
Economic results were gathered for
five major system components: center
pivot machine, service bundle (water
and power), pump components, labor,
and energy. The total annual cost of
some of these components decreased
with increasing irrigated area, while the
reverse was true for other components.
For example, the annual cost of the
center pivot machine was much higher
than any of the other components for
small irrigated areas. This changed as
irrigated area increased, with machine
cost decreasing to about the same as the
service-bundle and energy costs. Pump-
ing plant and labor costs also decreased
with increasing area and were the
smallest cost components in the higher
flow rate range.
Combining all costs resulted in the
relatively simple relationship illustrated
in figure 2. Total annual per acre costs
decreased sharply with increasing area
for small areas and then approached a
relatively constant cost of $80 per acre
per year for irrigated areas in the 125-
to 220-acre sizes. Importantly, neither
system size nor number of tows affected
the bottom line costs. Thus, small
towable center pivot irrigation systems
are a cost effective method to irrigate
crops in Alabama.
Rochester is Associate Professor of Agricultural
Engineering and Hatch is Assistant Professor and
Gilsi saGrdaeSuet 
fArclua
Gillespie is a Graduate Student of Agricultural
Economics and Rural Sociology.
Alabama Agricultural Experiment Station
THE PROBLEMS confronting
U.S. agriculture from the mid-
1970s to mid-1980s caused a farm
crisis with major challenges to young
college graduates seeking jobs in
agriculture. Employment opportunities,
both on and off the farm, were often
limited, sporadic, or nonexistent.
University recruiters and advisors were
asking if, in good faith, they could
recommend agriculture as a career. To
assess the impact of the farm crisis on
agriculture-related jobs, research turn-
ed to the actual experiences of
agricultural college graduates for
answers.
In a study conducted through the
Alabama Agricultural Experiment Sta-
tion, career experiences of students who
had been enrolled in an agricultural ma-
jor at Alabama A&M University,
Auburn University, and Tuskegee
University in 1977 (a time of peak
enrollments in agriculture at the State's
land grant universities) were surveyed.
The results provided detailed informa-
tion on 293 students. Of these, 34 (13%)
graduated from A&M, 177 (69%)
graduated from Auburn, and 44 (18%)
graduated from Tuskegee.
The educational accomplishments of
this survey group were varied. In 1977
the sample included students at all levels
of undergraduate education-freshman
through senior. Ten years later, 253
(87%) of the survey respondents had
graduated, most of them (82%) earning
a degree from the same university in
which they were enrolled in 1977. The
graduation years ranged from 1977
through 1985.
Among these graduates, 91%o com-
pleted their undergraduate education in
an agricultural major. The remaining
9% changed majors between their
enrolling in an agricultural major in
1976 and before completing their college
work. Animal science and forestry/for-
est management accounted for the
largest proportions of students, 17%
and 20%, respectively, table 1.
Many of these graduates continued
their academic studies at the graduate
and professional school levels. Masters
degrees were obtained by 23% of the
graduates, while 3% earned doctorates
and 7% received professional degrees,
primarily in veterinary medicine.
With these degrees in hand, were
graduates able to find jobs? More than
half reported their first job included
Alabama Agricultural Experiment Station
Job Opportunities
for Graduates Stable
Despite the Farm Crisis
J.E. Dunkelberger, S.F. Holland, and G.W. Wheelock
TABLE 1. GRADUATES IN AGRICULTURE-RELATED
ACADEMIC FIELD OR MAJORS
Major No. Pct.
Agricultural Economics .............. .......................... 10 4.4
Agribusiness................................................ 10 4.4
Agronomy ................................................. 17 7.4
Horticulture ................................................ 18 7.9
Forestry ....................................................... 17 7.4
Forest Management ............................................ 29 12.7
A nim al Sciences .... ............................................ 39 17.0
Poultry Science ................................................. 20 8.7
W ildlife ........................................................ 8 3.5
Fisheries ...................................................... 5 2.2
Veterinary M edicine' ........................................... 2 .9
Agricultural Education .......................................... 16 7.0
Agricultural Engineering ......................................... 7 3.1
Other
2  
...
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
31 13.4
TOTAL ..................................................... 229 100
'Student accepted into the Professional Veterinary Medicine program prior to completing
the B.S. degree in an agricultural major.
2
Biological science accounts for 23 of these majors at AU, where this was included in agriculture
during the 1970's.
agriculture-related duties. Of these, 17%
were employed in farming either for
themselves or someone else and 36%
were employed in agribusiness, a total
of 53%, table 2. By 1986, fewer than
half (48%) said they were currently
employed in farming or agribusiness.
This indicated only a modest shifting
out of agriculture-related employment
during the farm crisis years.
The majority of the students who
changed from an agricultural major to
a non-agricultural major entered non-
agricultural occupations. Only 12% of
non-agricultural majors said their first
TABLE 2. CLASSIFICATION OF FIRST AND
CURRENT EMPLOYMENT AS INVOLVING
AGRIBUSINESS OR FARMING DUTIES
Employment 
duties 
Employment
Farming...............17 NA'
Agribusiness ............ 36 48
Non-agricultural......... 47 52
Non-agricultural graduates
Agribusiness ............ 12 22
Non-agricultural ......... 88 78
'The question pertaining to current job did
not distinguish between farming and
agribusiness. Farming is included in the 48%
reporting agribusiness occupations.
employment after college was related to
farming or agribusiness. By 1986,
following several years in the work
force, 22% of this group had jobs that
involved agriculture-related duties.
These survey results showed a surpris-
ing stability in agricultural employment
despite the farm crisis. It indicated there
was no major exodus of young, college
educated people out of agriculture. But
it also revealed that many young people
who were interested in agricultural
careers never had the opportunity to
enter those fields. This suggests that the
real issue may be the failure of
agricultural job markets to provide
enough jobs for the number of young
people wishing to enter the agricultural
work force.
Comments from those surveyed also
indicated that many of the agricultural
graduates who did not find employment
in agribusiness were frustrated and
disappointed by the lack of opportun-
ity in these fields. As a group, female
respondents indicated they found even
less opportunity in agribusiness than
their male counterparts.
Dunkelberger is Professor and Holland is a
Graduate Research Assistant of Agricultural
Economics and Rural Sociology, and Wheelock
is Professor of Agribusiness Economics, Alabama
A&M University.
Llean, ury zurrounacings 
impede
4V
A.G. Appel
MASS MIGRATIONS of the
garden millipede are relatively
common in Alabama during
the late spring and early fall. Thousands
of millipedes may move from their
habitats in decaying leaf litter and under
debris into man-made structures such as
apartments, homes, and hospitals where
they become a nuisance. Although
relatively harmless, in severe cases, their
control may be desirable.
Barrier and soil treatments with
pesticides have provided only limited
control of migrating millipedes. Because
of numerous infestation reports and the
lack of basic biological information on
millipedes, the Alabama Agricultural
Experiment Station began studies in
June 1987 to develop a biologically
based control strategy for these
migrating insects.
Since millipedes do not possess the
water-proofing cuticular wax layer of
many other arthropods, moisture is an
important factor in their biology.
Laboratory studies were undertaken to
determine the rate of water loss and des-
iccation tolerance of migrating garden
millipedes. In addition, the effect of
water loss on millipede movement was
investigated. The practical results of
these studies were then taken into the
field to develop a control stratgegy.
Millipedes were collected from
around ornamental plantings and under
rocks outside an infested building. They
were maintained in plastic boxes con-
taining moist soil and provided water
and food. The size and weight of in-
dividual millipedes were measured prior
to the experiments. Groups of millipedes
were then held at 85 ?F and 007o relative
humidity, reweighed, and mortality
evaluated hourly for 10 hours. Then the
millipedes were completely dried at
140 F. From these data, the rate of
water loss, the percentage water content,
and the level of water loss causing death
were calculated.
To determine how desiccation affects
millipede movement, 1- to 5-hour desic-
cated millipedes were placed into
33-in.-diameter petri dishes lined with
filter paper. The distance moved in 1
minute was measured by covering the
petri dishes and tracing the movements
with a marker. Paper copies of the trac-
ings were retraced with digitization
equipment and the distance traveled
computed.
Migrating garden millipedes contained
approximately 6007o water, and they lost
water at an average rate of 7.707 per
hour. These factors caused millipedes to
die after about 6 hours of exposure to
warm dry air, or a loss of approximately
"a~ :9ar~~4-"
rw;
COMPARISON OF CUTANEOUS WATER LOSS
RATES AMONG SEVERAL ANIMALS
RELATIVE TO MAN
Animal Relative 
rate of
water loss
Earthworm ............... 8.33
Frog ...................... 6.25
Garden millipede.......... 1.63
American cockroach ....... 1.02
Man (not sweating)........ 1.00
Iguana lizard ............. .21
M ealworm ............... .13
460o of their total body water.
Even slight desiccation dramatically
affected millipede movement. After only
1 hour of drying, millipedes reduced
their distance moved per minute from
31 in. to 14 in., a 5570 decrease. Move-
ment decreased linearly with desiccation
time; there was no movement after 5
hours. Other movement experiments
have shown that millipedes are attracted
to moisture and are repelled by dry
environments.
These laboratory studies suggested
that moisture is a critical factor in
millipede distribution. Since millipedes
lose water rapidly, do not tolerate dry-
ing, decrease movement when desic-
cated, and are repelled by dry areas, a
control strategy based on moisture
reduction was devised. Lawns, or-
namental plantings, and debris often
form a continuous high humidity
pathway for millipedes to migrate.
Dethatching and removing moisture-
containing debris will aid in lowering
microclimate humidity and should also
repel millipedes.
This strategy was applied to the site
where millipedes were collected for the
laboratory experiments. Within 7 days
of a thorough outdoor 
clean-up,
primarily debris removal and close lawn
mowing, the average number of
millipedes entering buildings decreased
from nearly 200 per day 
to less than 15,
a 93%0 decrease. The numbers of
millipedes remained unchanged in the
one untreated control building.
These results suggest that a biologi-
cally based, non-pesticide control
strategy consisting of environmental
moisture reduction can effectively con-
trol migrating millipedes.
Appel is Assistant Professor of Entomology.
Alabama Agricultural Experiment Station
:4e
;itw
G"'k ~
: h_.rd
Adequate Prey 
Populations In 
Ponds
Assure Growth 
of Largemouth Bass
W.D. Davies
GOOD CONDITIONING and
growth are important factors in
largemouth bass production.
Research at the Alabama Agricultural Ex-
periment Station has shown that, for
largemouth bass to appear plump and ex-
press satisfactory growth rates, they must
feed efficiently. That means the energy
content of their food must be greater than
that required to forage. This situation ex-
ists when the pond has sufficient numbers
of prey of the appropriate size that are
readily available to the bass.
Adult largemouth bass feed primarily
on fish, although frogs, snakes, turtles,
and small ducks are also eaten. They can
swallow a bluegill or related sunfish ap-
proximately one-third their own body
length, though fish that are not as deep-
bodied as bluegill are more readily
swallowed.
A measure of the general well being of
fish populations is the relative condition
of the individual fish. For example, if a
number of bass of a certain length have
an average weight less than the Alabama
average (predicted from a large number of
measured lengths and weights collected
across the State), then it is likely that there
is a scarcity of the appropriate size prey
for that length of fish. On a relative 
scale,
poor condition would be expressed as a
value of less than 1.0 where 1.0 indicates
an average weight for a specific length
equal to the State average.
Sampling Southeastern farm pond fish
populations from 1977 to the present by
seining and electrofishing provided an op-
portunity to observe a wide variety of con-
ditions under which fish populations were
functioning. A total of 187 ponds was
sampled during the 10-year period, with
evaluations made of 1,029 largemouth
bass. Fish from the stomachs of these bass
were measured (total length) and com-
pared to the length and relative condition
of the bass. The stomach contents were
flushed from the bass into a container by
running a strong stream of water through
a tube into the stomach. Using this pro-
cedure, almost all of the bass were released
unharmed.
As illustrated by the drawing, results im-
plied that prey of about 15%0 of the bass'
length must be readily available for large-
mouth bass to maintain a relative condi-
tion of 1.0. Other factors also appeared
to affect this relationship. For instance,
The chart shows the weight-to-length ratio of largemouth bass in relation to the size of prey
available, with 1.0 representing an ideal relative condition for bass.
rooted aquatic vegetation, if abundant, ap-
peared to reduce feeding efficiency. Also,
fish populations in ponds that were not
well fertilized (did not have desirable
phytoplankton "bloom") had average
relative condition factors less than 1.0.
Results of the study indicate that good
management practices can help correct an
imbalance in largemouth bass condition.
Such practices may include the elimination
of the rooted aquatic vegetation and fer-
tilization to increase production. Harvest
regulations also appear to be helpful.
Harvesting thin and "racy" looking fish
while leaving the plump, fast-growing fish
in the population also can help improve
the relative condition of the fish.
The research did encounter small bass
(12-in.) in relatively poor condition while
the few large bass present were consider-
ably more robust. This indicates low
growth rates and reproduction in the prey
populations, which can sometimes be so
severe that returning bass to the pond will
not be enough to restore a balanced fish
population. Under these conditions, addi-
tional management inputs may be required
to sustain quality fishing in the pond.
Davies is Professor of Fisheries and Allied
Aq uanult ures.
Relative condition
of largemouth bass
1.5 r
1.0
0.5
0.0
. k ,.
rI
.05
4A
I
0.15 0.25
Ratio of prey length to bass length
Disease Resistance an Advantage
of New Auburn Plum Varieties
J.D. Norton, T.L. Kamps, and T.E. Conaty
LUM PRODUCTION in the
Southeast is limited because com-
mercial varieties are susceptible to
black knot, bacterial canker, bacterial
fruit spot, and plum leaf scald. Thus,
there has been a need for varieties resis-
tant to these damaging diseases.
Four varieties developed by the
Alabama Agricultural Experiment Sta-
tion (AU-Amber, AU-Rubrum, AU-
Rosa, and AU-Cherry) should help
overcome the disease problem. Au-
Rubrum, AU-Rosa, and AU-Cherry
proved resistant to all of the diseases
listed, and AU-Amber was resistant to
all except black knot disease.
The new varieties, developed for areas
that receive 700-800 hours of chilling
below 45 ?F, resulted from crossing
native plums with commercial varieties.
Resistance to bacterial, fungal, and viral
diseases came from the native plums,
while the commercial varieties in the
crosses provided desirable fruit quality.
Evaluations of the new varieties were
made during 1979-87 in test plantings at
the Main Station, Auburn; Chilton Area
Horticulture Substation, Clanton; Pied-
mont Substation, Camp Hill; Gulf
Coast Substation, Fairhope; Wiregrass
Substation, Headland; and E.V. Smith
Research Center, Shorter. Observations
were made on fruit and tree
characteristics, disease injury, and yield.
Recommended pesticide sprays were
applied to the test trees, but susceptible
trees at all locations showed injury from
brown rot, bacterial fruit spot, leaf spot,
and canker. However, injury from black
knot was severe only on susceptible
varieties at the Chilton Area Hor-
ticulture Substation. Plum leaf scald in-
jury was recorded on infected trees in
the disease screening planting at
Auburn, where trees had been infected
by double budding 1-year whips with in-
fected wood.
The varieties were tested before being
named, as Methley 12-10 (AU-Amber),
Crimson M-1 (AU-Rubrum), Santa
Rosa A-5 (AU-Rosa), and Methley C-50
(AU-Cherry). The original designations
indicate parentage of the new varieties.
Low disease severity of the new
varieties (except for AU-Amber's
susceptibility to black knot) is apparent
from data in table 1. They are similar
in resistance to AU-Producer, AU-
Roadside, and Crimson, other Auburn
releases. Other commercial varieties in
the comparisons (Methley, Morris,
Ozark Premier, and Santa Rosa) were
much more susceptible.
Fruit quality of the new varieties was
rated excellent. All had peak maturity
around June 19-24, except AU-Amber
10
which peaks June 2, table 2.
Yield of the new plums com-
pared favorably with earlier
Auburn releases and with the
standard Methley variety. De-
tails about each of the four
follow:
AU-Amber-red/purple skin, yellow/
amber flesh; small fruit with medium
firmness limit it to roadside and local
markets and home use.
AU-Rubrum-maroon skin, red
flesh; large, firm fruit makes variety
suited for commercial market.
AU-Rosa-red skin, yellow/red flesh;
large, firm fruit suitable for commercial
market.
AU-Cherry-red skin and flesh; small
fruit of medium firmness makes it
desirable for home production only.
TABLE 2. SELECTED FRUIT CHARACTERISTICS
OF PLUM VARIETIES AT AUBURN
Ftuit Fruit Sol- 
Peak
Variety size firm- uble harvest
ness' solids date
In. Pct.
AU-Amber .. 1.5 7.2 18.0 6/2
AU-Cherry 1.3 7.0 18.0 6/23
AU-Roadside 1.9 6.8 17.2 6/23
AU-Rubrum... 1.9 8.0 15.6 6/19
Crimson ..... 1.6 8.3 16.3 7/10
Homeside .... 2.2 6.6 18.8 6/22
Methley ..... 1.4 6.6 18.5 6/7
Morris ...... 1.8 7.5 13.4 6/20
Ozark Premier 2.1 6.8 15.7 6/29
Santa Rosa .. 1.7 7.7 16.7 6/22
'Fruit firmness: 0-10, 0 = softest; 10 = firmest.
Tree vigor and tolerance to plum leaf
scald are primary advantages of the new
varieties. Trees of these resistant
varieties were observed to be vigorous
where plum leaf scald was present,
whereas trees of susceptible varieties
grew slower. Tree vigor is an important
factor in the Southeast, and plum leaf
scald is implicated in phony peach dis-
ease of plums and peaches. Therefore,
disease resistance of these new varieties
should prove valuable. Short tree life
and low productivity of susceptible
varieties in the test make them unecon-
omical for commercial production.
Trees of the new varieties should be
available from wholesale and retail nur-
series for planting in the winter of
1988-89.
Norton is Professor, Kamps is Research
Associate, and Conaty is a Research Assistant of
Horticulture.
Alabama Agricultural Experiment Station
TABLE 1. DISEASE SEVERITY ON PLUM VARIETIES IN EXPERIMENTAL
PLANTINGS AT AUBURN, CAMP HILL, CLANTON, FAIRHOPE,
HEADLAND, AND SHORTER, 1979-87
Disease index'
Variety Bacterial Bacterial Bacterial Black Brown Plum leaf
fruit spot leaf spot canker knot
2  
rot scald'
AU-Amber ................ 0 0 0 5 2 0
AU-Cherry ................ 0 0 0 0 2 0
AU-Producer .............. 0 0 0 0 2 1
AU-Rosa ................. . 0 0 0 0 2 1
AU-Roadside .............. 0 0 0 0 2 1
AU-Rubrum ............... 0 0 1 0 2 1
Crimson .................. 0 0 1 0 2 3
Homeside ................. . 0 0 1 1 3 1
M ethley ................... . 5 5 5 5 3 4
M orris.................... 1 2 2 2 2 2
Ozark Premier ............. 0 1 1 1 3 4
Santa Rosa................ 5 5 5 5 3 5
'Disease index: 0=0, 1 1-20%, 2=21-40, 3 =41-60, 4=61-80, and 5=81-100% of fruit, leaves,
and trees infected.
2
lnfection and severe injury of susceptible trees only at Chilton Area Horticulture Substation.
'Injury recorded on trees in disease screening planting at Auburn. Trees infected by double bud-
ding 1-year whips with infected buds.
DUE TO heavy selection pressure
placed on growth rate, broiler
breeder males overeat and become
obese, resulting in decreased flock fertil-
ity. Preventing male obesity by restricting
feed is difficult because they are subjected
to intense feed restriction during the grow-
ing period, then essentially full-fed during
the breeding season. Males, being larger
and more aggressive than hens, eat as
much as desired.
Overcoming the problem has been dif-
ficult because little is known about tem-
porary or permanent effects of feed restric-
tion on male body composition or repro-
duction. Therefore, research was con-
ducted at the Alabama Agricultural Exper-
iment Station to investigate effects of three
common feeding regimes during the grow-
ing period (3-22 weeks of age) on body
composition and reproductive perform-
ance of breeder males. Feeding regimens
included (1) limited daily (LD) in which
birds were fed breeder recommended
amounts of feed on a daily basis, (2) skip-
a-day (SAD) in which birds were fed twice
the recommended amount of feed every
other day, and (3) limited time (LT) in
which the birds were allowed to eat for a
limited time period each day.
During the growing period, body
weight, feed consumption, age at first
semen production (sexual maturity), and
litter moisture were measured. At 22 weeks
of age, one-half of the birds in each treat-
ment were randomly selected, and testes
and liver weights and body composition
were determined. The remaining birds
were placed on unlimited feeding to
stimulate commercial conditions during the
breeding period. From 22 to 34 weeks of
age, body weight, semen weight, and
sperm concentration were measured at
regular intervals. At 34 weeks of age, testes
and liver weights and body composition
were determined.
Body weights of the three treatment
groups were similar throughout the grow-
ing period. However, limited daily birds
consumed less feed per day than the other
groups, indicating more efficient use of
feed. Litter moisture during the growing
period ranged from 570/0 for limited time
and 52% for limited daily feeding to 32%
for skip-a-day regimen. Litter moisture
levels for limited time and limited daily
were higher than optimum (20-40%), in-
dicating a difference in water consumption
among the treatments. This difference is
important due to cost of litter replacement
and increased risk to flock health.
Alabama Agricultural Experiment Station
Age at sexual maturity ranged from 170
days for limited daily to 180 days for skip-
a-day. Stress of having every other day
without feed may be sufficient to slow
reproductive development. Body composi-
tion and testes and liver weights at 22
weeks were not affected by treatment.
When the birds were placed on unlim-
ited feeding, body weights of all groups
increased dramatically. The limited daily
birds gained weight most rapidly, prob-
ably due to the higher feed efficiency
established during the growing period,
compared to skip-a-day and limited time
feeding. By 28 weeks, however, there
were no differences in body weight due
to treatment.
Reproductive performance was af-
fected by feeding regimen. Semen
weight and spermatozoa concentration
were higher in skip-a-day males than in
limited daily males. Semen production
also declined less rapidly after 30 weeks
of age in skip-a-day males, figure 1.
At 34 weeks of age, testes weights
were lower in limited daily birds than in
skip-a-day or limited time birds (LD 1.5
oz., SAD 1.7 oz., and LT 1.9 oz.). The
limited daily birds had extremely en-
larged, yellow, fatty, friable livers when
compared to the other groups. The lim-
ited daily birds had more body fat and
less body protein than skip-a-day or lim-
ited time birds at 34 weeks, figure 2. These
differences occurred at similar body
weights among treatment groups.
FIG. 2 (above). Effects of feeding regimen
during growth on body composition at 34
weeks.
FIG. 1 (below). 
Effects of 
feeding 
regimen
during growth on spermatozoa number from
26 to 34 weeks of age.
Spermatozoa number (x 10 9 )
12
9(.---
. /
...... Skip-a-day
3 n- 
- - Limited time
----- L im ited daily
0 26 27 28 
29 30 31 32 
33 34
Age, weeks
Although maintaining desirable body
weight is important, it should not be the
only criterion for selecting a feeding pro-
gram for growing birds. The results of this
study can be summarized to indicate that
feeding programs have these effects:
1. Litter moisture content-higher than
desired on limited time and limited daily
feeding.
2. Feed efficiency-limited daily birds
made most efficient use of feed.
3. Adult body composition-limited
daily birds were fatter and had less body
protein.
4. Male reproductive performance-
skip-a-day feeding resulted in higher semen
weight and spermatozoa concentration.
Sexton is a Graduate Research Assistant and
Renden is Associate Professor of Poultry Science.
11
L.i l.JL a a C -a ., ,Ji x i i ,..t 4
For North Alabama Soybeans
C.H. Burmester, J.F. Adams, and J.W. Odom
RESEARCH with soybeans in
Alabama as early as 1907 showed
yield increases from liming acid
soils. Only recently, however, have yield
increases been observed from additions
of small amounts of molybdenum (Mo)
to the soils of northern Alabama.
The Alabama Agricultural Experi-
ment Station established on-farm pro-
grams of soil fertility experiments in
1976 for the northern counties of
Alabama to improve soil-test calibra-
tion. A part of this program was to iden-
tify critical soil pH for soybean produc-
tion on the three major soil areas of
north Alabama. These areas were the
sandy soils of the Appalachian 
Plateau,
the silty clay soils of the Tennessee
Valley, and the silty soils of the
Highland Rim bordering Tennessee.
It soon became apparent that the
critical pH varied widely 
among sites,
suggesting that more than one soil fac-
tor was involved. In several of the
unlimed test plots, soybean plants had
a noticeably light green color. This in-
dicated a possible nitrogen deficiency
caused by poor N fixation by soybean
rhizobia. A possible Mo deficiency was
suspected since Mo is needed in nitrogen
fixation and Mo availability is less on
acid soils. The possibility of a Mo defi-
ciency was unexpected since earlier tests
EFFECTS OF LIMING AND Mo ON YIED OF
SOYBEANS IN NORTH A ABAMA, 1981-85
Yield/acre
Site Unlimed 
No lime Lime
soil pH -Mo 
+Mo 
-Mo 
+ Mo
Bu. Bu. Bu. Bu.
1... 4.6 10 13 16 16
2... 4.7 11 13 13 14
3... 4.8 28 37 46 46
4... 4.9 27 26 31 37
5... 4.9 31 34 35 34
6... 5.0 35 38 45 47
7... 5.0 24 28 30 29
8... 5.2 22 22 22 22
9... 5.3 44 50 54 51
10... 5.3 30 38 43 44
11... 5.3 22 31 30 32
12... 5.4 50 53 53 56
13... 5.4 26 37 40 38
14... 5.6 24 30 25 28
15... 5.6 20 26 31 34
on soils in north Alabama had shown no
response to additions of Mo fertilizers.
Starting in 1981, on-farm experiments
were established to identify the soil fac-
tors causing soybeans to respond to lim-
ing. Lime was applied in farmers' fields
at rates of 0 and 2 tons per acre in late
winter. Farmers planted these test areas
(one in each field) along with the rest of
the field and followed normal produc-
tion practices. To check for response to
Mo, a sodium molybdate solution was
sprayed on two rows at a rate of about
1 oz. per acre in both the limed and
unlimed plots about 2 weeks after soy-
bean emergence. Fifteen tests were con-
ducted on sites between 1981 and 1985
with unlimed soil pHs ranging from 4.6
to 5.6.
Liming increased soybean yields at 12
of the 15 sites, see table. Of the 12 sites
that responded to lime, 11 also showed
a yield increase with Mo addition. Soy-
beans in the unlimed plots were a
noticeably lighter green color and leaf
analyses confirmed nitrogen deficien-
cies. Deficiency symptoms did not ap-
pear until soybeans reached the bloom
stage, when the soybeans' requirement
for N drastically increases. These N defi-
ciency symptoms were seen in soybeans
grown in all three soil areas of north
Alabama. Addition of lime or Mo cor-
rected discoloration and resulted in
higher yields.
Addition of Mo was found to produce
the same yield increase as liming at five
sites, while at seven sites liming Iro-
duced the larger yield increase. In three
cases, addition of lime plus Mo in-
creased soybean yield more than liming
alone. The average soybean yield in-
crease found in these tests was 6.0 bu.
per acre from Mo addition (11 sites), 8.3
bu. per acre from liming (12 sites), and
6.8 bu. per acre from lime plus Mo (3
sites).
Results of these tests suggest that Mo
deficiency is extensive on acid soils in
north Alabama, a condition which
would not have been found through soil
testing. Addition of lime or Mo gener-
ally has increased Mo availability and
corrected the deficiency. Liming is the
preferred treatment as it can correct
other problems, such as aluminum and
manganese toxicities, associated with
acid soils. However, the low cost of Mo
treatment ($1-2 per acre) and the
possibility of a response at higher pH
values make Mo application attractive
in northern Alabama for optimum soy-
bean production.
Molybdenum is needed in only a small
amount by the soybean plant, so no
more than the recommended dosage is
indicated. Molybdenum can be applied
as a seed treatment or as a foliar spray
prior to blooming of the soybeans. In
either case, 1 oz. per acre of sodium or
ammonium molybdate should be suffi-
cient.
Burmester is a Research Associate, Adams is
Assistant Professor, and Odom is Associate Pro-
fessor of Agronomy and Soils.
Alabama Agricultural Experiment Station
~i
..
RODUCING 
PLANTING 
seed 
f'r'
for game-food crops offers op-
portunities for a farm enterprise.
There is a strong interest in such crops Tolerance To 
Posterergence-
as American jointvetch for deer food
and Comanche partridge pea and Am-
quail lespedeza for quail food. As a
result, there is a shortage of planting 
A pp lied H er Bcides
seed. R H Walker, D R Wyatt, and P B ALoes
As with any other crops, weed con-
trol is essential for economical and ef-
ficient production of seed. Broadleaf
weeds are particularly troublesome in
the desirable game-food crops. Since no
information was available concerning
tolerance of these plants to 
herbicides,
a greenhouse study was done to deter-
mine response of American 
jointvetch,
Comanche partridge pea, and Amquail
lespedeza to seven postemergence-
applied herbicides.
Ten mechanically scarified seed of the
appropriate species were planted in
quart containers that contained 2 lb. of
a sandy loam soil amended with peat
moss. Soil-test results indicated a pH of
6.2 and high levels of P and K. All con-
tainers were watered daily and plants
were thinned to two per container within
10 days of emergence. Natural sunlight
was supplemented with artificial 
lights
which were set for 16 hours light and 8
hours dark. Day temperature max-
imums averaged 90
0
F and night
temperature lows averaged 70
0
F.
Relative humidity during the day
averaged 500o.
Herbicides were applied when the
jointvetch plants averaged 5 in. in height
and had nine fully expanded leaves, par-
tridge pea averaged 5 in. tall and had six
leaves, and the lespedeza plants averag-
ed 4 in. in height and had three leaves.
All herbicides were delivered in a
volume of 15 gal. per acre. Ortho X-77
nonionic surfactant was included at
0.250o by volume in all treatments.
Data collected included injury ratings
using a scale of: 0 none; 1 to
29 = slight; 30 to 59 = moderate; 60 to
99 =severe; 100 =death. All plants were
harvested for dry weight determinations
after the final injury rating. Results arc
reported in the table.
American jointvetch and Amquail
lespedeza tolerated three of the seven
selected herbicides. Injury was slight and
dry weight was equal to the untreated
when these species were treated with
2,4-DB (Butyrac? or 
Butoxone? ),
Alabama A gricultural Experiment Station
AVERAE RESPONSE OF GAME-FOOD CROPS FO SEVEN POSTEMERGENIE-APN 1ED
HrRKICIDtS, THREE EXPF RIMENTS, 1987
Comanche Anerican Amquail
Herbicide' and rate/acre partidge pea jointvetch lespedeza
Injury Wcight'
2,4-DB13 amine, lb............
Scepter, '/lb ...............
MSMA, 1 lb.
Classic, '/, oz. ..............
Blazer, !/ lb. .................
Basagran, 14 lb................
2,4 1) amine, % Ib.............
Nontreated
1. Gins
30 1,35
57 2.84
34 3.13
33 1.07
)0 .08
2 4.14
35 1.69
0 5.35
Injury WXeight
Pc. Grains
9 4.03
53 2.55
65 1.30
74 .57
100 .15
9 4.30
11 4.53
0 4.36
Injury Weight
Pct. Graims
13 3.00
48 1.31
88 .17
87 .14
85 .6
8 3.72
9 2.47
0 2.40
All rates are given as active per acre, except 2-4-DB and 2,4-D which are acid equivalent/acre;
Ortho X-77 nonionic sut factant included at 0.2511o by solume.
Injury ratings taken 12 to 24 days after hetbicide treatment.
Average grams dry weight per container 24 to 33 days alter treatment (1 oz. =28 grams).
2,4-1) (" ccdar 64' ), ot IBasagran " .
These three herbicides show potential
for control of a large number of
broadleaf species in both Aterican
jointvetch and Amquail lespedeza.
Earlier Experiment Station research
had revealed that AU Lotan and AU
Donnelly low-tannin sericea lespedeza
tolerated three applications of 2,4-DB
('2 lb. acid equivalent per acre per
application) or 2,4-D (4 lb. acid
equivalent per acre per application)
when applied to young seedlings. It is
highly probable that Amquail lespedeza
will respond in a similar manner to these
two herbicides, but this has yet to be
determined.
Comanche partridge pea was injured
by all herbicides except Basagran.
However, there was enough tolerance to
\1\IA (Bttno 6" 1 anhied at 1' lh.
1 l
Y~
W"! 1' L +
00 
JP,
act sc pet acre to \at tat cxaluatton of
this herbicide at lower rates. Tolerance
to Basagran is tot sufficient to an-
ticipate good weed control in partridge
pea at this time because Basagran does
not control sicklepod and several of the
annual morningglories. In another ex
periment comparing herbicide tolerance
of the native Alabama partridge pea and
Comanche, both responded the same to
these seven herbicides.
Since the game-food crops tested
proved tolerant to some of the seven
herbicides, there is hope for effective
weed control programs. 
At this time,
however, none of these is labeled for
weed control in partridge pea, joint
vetch, or lespedeza.
Walker is Assoctate Professor and Wyatt and
Abnev are Research Asststants of Agronomy and
P4
Marketing and Processing Viewed As
Major Constraints to Catfish Farming
CATFISH FARMING has been
the most rapidly expanding Ala-
bama food producing industry in
the past decade. Like other aquacultural
enterprises, catfish production offers the
promise of profitably combining the
State's unique water, land, and climate
resources in an era of stagnant prices for
many other commodities. Several public
agencies with agricultural and natural
resource management responsibilities
have worked together to assist catfish
producers in responding to the new set
of opportunities.
In fall 1987, a Statewide survey of ad-
ministrators and officials in public agen-
cies serving the aquacultural industry
was undertaken. The 144 respondents to
the mail questionnaire represent a 95%
response rate. The study, conducted by
the Alabama Agricultural Experiment
Station, asked these individuals to rate
a series of possible constraints or sources
of difficulty for the future of Alabama
aquaculture. The table shows the top 15
constraints as rated by public agency
personnel in the sample.
Marketing and the availability of pro-
cessing facilities were viewed as major
constraints by more than 83% of the
respondents. Currently, catfish process-
ing plants are located only in the
Greensboro area in Alabama. Producers
often express concerns about the
somewhat lower prices (about 5? per lb.)
they receive for catfish in Alabama
relative to Mississippi, a consequence of
more facilities and greater competition
for product that occur there. Clearly,
the sale and utilization of aquacultural
commodities is the major concern in the
industry. The availability of more pro-
cessing plants in other parts of the State
would enhance the expansion of catfish
production.
Off-flavor detection is a concern for
many catfish farmers because this deter-
mines the quality of their product and
J.J. Molnar and S. EI-Ghamrini
the price received. Thought to be caused
by geosmin found in certain pond
algaes, off-flavor can force growers to
hold stock until the problem corrects
itself or go to the expense of moving fish
to uncontaminated ponds.
Only 23% saw production advice as
a limitation. About 30% saw the need
for adequate financial management ad-
vice as a constraint. The lack of will-
ingness by Alabama farmers to innovate
was viewed as a constraint by about
31%o. About 27% saw the need for
quality control in fish production and
processing as a constraint.
Genetic stock and water availability
were seen as major problems by about
23% of the sample. Fish disease treat-
ment was felt to be a limitation by only
about 21%.
Less than 21%0 thought that water
quality, legal definitions of fish culture,
fish feed, and seedstock supplies were
constraints on the industry. An addi-
tional four items were rated by the
public officials, but were noted as con-
straints by less than 10% of the sample.
These included: adequate feed for-
mulating, consumer acceptance, dam in-
spection, and water discharge
regulations.
The data profile the perceptions of
public agency administrators who have
extensive contact with and knowledge of
the aquaculture industry in Alabama.
Financial and marketing concerns
dominate their view of the future of the
industry. Producers, however, may have
somewhat different perspectives on
where their industry is going and how
it will get there, but they are not likely
to differ greatly on the relative impor-
tance of the major issues facing fish
farming in the State.
Molnar is Professor of Rural Sociology aid El-
Ghamrini is a Graduate Student of Fisheries and
Allied Aquacultures.
Alabama Agricultural Experiment Station
14
xood structural plywood pro-
duced primarily from Douglas
tir in the Pacific Northxest began to be
utilized as sheathing in house construc-
tion in the United States. Softwood
plywood soon replaced lumber in hous-
ing as floor underlayment and subfloor-
ing and roof and wall sheathing because
of its high strength, dimensional stabil
ity, and significantly lower material and
installation costs than tongue-and-
erooxed lumber.
In 1960, production of softwood
structural plywood from souther n
yellowx pine began in the Southeast. Cur-
rently, about 5007o of all softwood
plywood in the United States is pro-
duced trom southern yellow pine.
The next change was the introduction
of non-veneered structural panels,
primarily oriented strand board (OSB)
and waferboard. In 1987 these products
accounted foi approximately 13(7o of the
total xood panel sheathing used for
floors, roofs, and walls in housing.
All of these non-veneered panels arc
fabricated with exterior type resin
(phenol-formaldehyde) and approved
for use in housing by all regulatory
agencies and codes. However, there are
significant ditferences among the dif-
ferent types of panels, and recent tests
at the Alabama Agricultural Experiment
Station exaluated the mechanical and
structural properties of southern pine
plywood (3-ply, !/-in. thick), southern
pine OSB (oriented flakeboard, 7/16-in
thick), and aspen aferboard (' -in.
thick).
From each panel type, three panels 4
ft. xide by 8 ft. long xere randomly
selected and cut into standard small
specimens for flexure (stiffness and
strength) testing. Flexure testing was
with span parallel to face particle orien-
tation for the oriented flakeboard and
span parallel to the tace veneer grain for
plywood. Six specimens from each panel
xere tested to destruction under each of
two test conditions: (I) Original. condi-
tioned to equilibrium at 65%Io relative
humidity and 72 degrees F, and (2) cy-
cled, soaked for 48 hours in xater and
then reconditioned to original condition.
The flexure properties of the three
panel types are shown in the table. There
xas a significant difference in panel
weight ranging from 45 lb. for southern
pine plywood to about 48 lb. for the
other two panels.
Alahama Agricultural Experiment Station
Oriented Strand Board and
Waferboard Competitive With
Structural Plywood
E.J. Bihlis
Test samples shown are (A) waferboard, (B) southern pine plywood, and 
(C) oriented strand
board.
In Ilexure with spans parallel to face
orientation, or veneer grain, the stiffness
and strength were higher for the
southern pine plywood, followed by the
OSB from southern pine and the aspen
waferboard. Although the southern pine
plywood 'as 13% less dense than the
OSB, after cycling it was 2880 stifler
and 208 o stronger than the OSB. On
\Ioiii e
the other hand, the OSB panels in the
direction of flakcs aftet cxcling were
3300 stiffer and 30%7o stronger than ian-
domly oriented aspen waferboard.
Though retail prices vary\, plywood
sheathing ot approximately equal
thickness costs about 20%7o more than
OSB or aferboard.
Itibli is 0201es r o orests.
PaIniel
(southerr
o)ricntcd
Ilakehoi
iout he
WaierTh
(aspen)
n pine)
Ird
I pine)
),aLd
( )i illli
( xlcd
Reiuction I01)
or)iiaii
(dicici i Oo)
eigll Si ill c>
1h. Lb. /sq ill.
17.7
49 699.4>_
464,4>
(33.6)
48 477, 33)
349.4y5s
(26.8)
I k'.tre
Siiei ill
i/i sq. inl.
2,650
(30.7)
x,1(1
(20. )
I'll Al R,11 PRO N Rrirs (A 1111 SIRrcH R:V wOOU PAM I
Panel type
)s Show Promise As Energy
roducers Of The Future
.I. Bransby, C.Y. Ward, C.C. King, Jr., and G. Sims
MEETING DAY-TO-DAY energy
needs by growing crops may
seem far-fetched. Yet, judging
by the extensive research effort in this
field, many scientists and institutions
consider such a possibility entirely
feasible.
Plant material (known as "biomass")
is obtained from woody or herbaceous
energy crops and can be converted by
various processes to liquid fuel, gases
such as methane, or thermal energy.
Due to the relative abundance of con-
ventional energy sources, such as fossil
fuels and atomic energy, and the adap-
tation of technology to these energy
sources, biomass has not yet received
adequate research and development at-
tention as an energy resource. Although
interest in biomass as an energy source
has been sporadic and surged periodi-
cally only in association with energy
crises, certain institutions (the Tennessee
Valley Authority, the Gas Research In-
stitute, and the U.S. Department of
Energy) have developed ongoing
bioenergy research programs.
The Alabama Agricultural Experi-
ment Station has been a cooperator in
new research sponsored by the U.S.
Department of Energy's Biofuel,
Municipal Waste, and Technology Divi-
sion, and coordinated by the Oak Ridge
National Laboratory. The aim of the
research is to evaluate herbaceous crops
for biomass production in the
Southeast.
Warm-season crops in the research in
clude annuals (sweet sorghum and
pearlmillet) and perennials (ber-
mudagrass, johnsongrass, switchgrass,
Weighing samples to determine biomass yield
in field trials.
.and cntca lepedeza). Cool-season
species are mainly rye mixed with
various annual legumes. Tall fescue is
the only temperate perennial. These
cool-season crops were planted in rota-
tion with summer annuals or into the
iod of summer perennials following fall
r\esting of summer growth.
ienerally, sweet sorghum has been
best summer crop, producing over
15,000 lb. per acre in a good season at
some sites, see table. However, a disad-
vantage is that this species requires an-
nual planting and its soil protection
capability is lower than for perennials.
The most successful summer peren-
nial species have been switchgrass,
johnsongrass, and sericea lespedeza.
These produced up to 8,000 lb. per acre
in low rainfall years. In 1987, 
however,
elephantgrass (a sub-tropical perennial
grown in south Georgia and Florida)
produced over 20,000 lb. per acre in
spite of erratic rainfall. The problem
with this species is low winter survival.
Therefore, specialized management
practices must be developed to grow this
productive crop in north Alabama.
Production from cool-season species
has been as high as 6,942 lb. per acre,
with most of this composed of rye. Con-
sequently, rotation of warm-season
followed by cool-season crops appears
to have potential for production ex-
ceeding 20,000 lb. per acre per year.
Cost of biomass production under these
high yielding production systems is
estimated at around $40 per ton.
The cost of converting this biomass
to liquid fuel would result in a price of
about $3.00 per gal. with existing con-
version technology. Thus, fuels from
biomass would not be competitive at
current prices of gasoline. However, in
the event of cheaper biomass production
and conversion methods and higher
prices of gasoline that may occur in the
future, this situation could change. In
many European countries with strong
economies, the price of gasoline is cur-
rently similar to the production cost of
fuels from biomass.
Bransby is Associate Professor, Ward is Pro-
fessor, King is Professor Emeritus, and Sims is
Research Associate of Agronomy and Soils.
AVERAGE BIOMASS YIELDS 01 SOME TEST SPECIES GROWN ON MARGINAL
LAND AT FOUR SITES IN ALABAMA FROM MAY 1985 TO MAY 1986
Crop Dry 
matter yield/acre
Summer Winter Total
Lb. Lb. Lb.
Sweet sorghum-rye + sweet clover ............................. 15,989 6,942 22,931
Johnsongrass alone ........................................... 8,995 0 8,995
Pearlm illet-rye + vetch ....................................... 11,743 4,265 16,008
Sericea-rye ......... ................................. . ..... 3,226' 4,896 8,122
Switchgrass-rye + vetch ....................................... 1,789' 4,163 5,952
'This was the establishment year for these two perennial species and yields were lower than would
he expected in subslequent vears.
ALABAMA AGRICULTURAL EXPERIMENT STATION
AUBURN UNIVERSITY
AUBURN UNIVERSITY, ALABAMA 36849-5403
Lowell T Frobish, Director
POSTMASTER-Address Correction Requested
NON-PROFIT ORG.
POSTAGE & FEES PAID
PERMIT No. 9
AUBURN, ALA.