RESEARCH RESULTS FOR NURSERYMEN
Henry P. Orr, KennethC. Sanderson, Raymond 
Self, Willis C. Martin, Jr.,
Harrison M. Bryce, Newton J. Hogg and Landon C. Miller
Horticulture Series No.10
AGRICULTURAL EXPERJMENT STATION
QF
AUBURN UNIVERSITY
E . V. Smith, Director 
Agitl6 
uun lbm
August 1968 Auburn,. Alabama
I. NATIVE PLANTS FOR ROADSIDE CONSERVATION AND BEAUTIFICATION
(Orr, Bryce and Hogg
Shrubs, small trees, and standard trees in roadside landscapes are needed for
conservation, safety and beauty. Alabama has a wealth of native plants possibly
desirable for multiple purposes along the roadsides.
For the past five years the Department of Horticulture, Auburn University has
cooperated with the Alabama State Highway Department in an effort to determine trees,
shrubs, and vines adaptable for use on Alabama highways.
Since 1966, research has been concentrated on evaluating native plant material.
Earlier evaluations of introduced and native species were reported in "Research
Results for Nurserymen," Horticulture Series No. 8, 1967.
A part of the current study is devoted to the evaluation of planting established
on portions of the interstate system in Alabama now open to the public. Three areas
of the state were selected for study: 1-65 in Escambia, Conecuh and Butler counties;
1-65 in Jefferson, Blount and Cullman counties; and 1-59 in DeKalb county.
Each area was visited in the spring of 1967. Numerous plants of several species
were observed in one or more locations. Sample plants were tagged, measured for height
and width (or caliper for trees) and given a growth rating. These areas were visited
again in the fall and plants remeasured to determine the year's growth. Another growth
rating was made.
Several native standard trees were considered satisfactory in the Southern
portion of the State. These included Sycamore, Tuliptree, Southern Magnolia, Bald
Cypress, Red Maple, and Laurel Oak. Other native trees evaluated and found lacking
in some of the characteristics desirable for low-maintenance plantings includes
Eastern Red Cedar, American Holly, Sweet Gum and Scarlet Oak.
Of the four native small trees planted in the Southern portion of the State,
Flowering Crabapple and Eastern Redbud were considered satisfactory. Flowering Dog-
wood varied considerably from site to site. This species planted on well drained
slopes averaged slightly more growth and showed better vigor than when planted in
level, moist areas. White Fringe Tree was rated poor.
Relatively few species of native shrubs were planted in this Southern area.
Southern Waxmyrtle was rated best of seven native shrubs used. This shrub also
proved to be an excellent choice in the Cullman area where it survived well and
made excellent growth.
Seven species of small native trees were used in the two Northern areas. Only
Flowering Crabapple was rated good out of this group including White Fringe Tree,
Persimmon, Eastern Redbud, Flowering Dogwood and Common Smoketree. Washington
Hawthorn was satisfactory in the Ft. Payne area.
Eighteen standard native trees were evaluated in the Cullman and Ft. Payne
areas. Species showing promise included Red Maple, Bald Cypress, Sycamore, Cotton-
wood, Loblolly Pine and Slash Pine.
2
In a continuing effort to determine native material suitable for roadside
use, twenty-four species of native trees, shrubs and vines were planted in plots
along both sides of I-85 near Auburn in March 1967. These sites included dry, open,
undisturbed locations, damp low locations, exposed bank locations, and shady
locations.
Where possible, two sizes of each species were obtained to allow a comparison
of survival and rate of growth.
After one year's evaluation, several native species, not in use on our high-
ways at the present time, may be useful as well as attractive when used in selected
sites. These irclude: Ninebark, Devils Walkingstick, American Bittersweet, Grey
Dogwood, and Vernal Witchhazel.
II. EFFECTS OF GIBRBERELLIC ACID ON GERMINATION OF SEEDS FROM SELECTED NATIVE TREES
AND SHRUBS
(Hogg and Orr)
Tests were conducted to determine the effects of 24-hour treatments in three
concentrations (100,200,400 p.p.m.) of gibberellic acid (75% K salt) on germination
of seeds from Acer floridanum, Florida Maple; Diospyros virginiana, Common Persimmon;
Halesia carolina, Carolina Silverbell; Callicarpa americana, American Beautyberry;
Osmanthus americanus, Devilwood Osmanthus and Symphoricarpos orbiculatus, Indian
Currant Coralberry. Seed replications were germinated in clear plastic boxes on a
layer of cellulose paper in the controlled environment chamber. Temperatures were
maintained t 68 F in darkness (16 hours) and 86 F (8 hours) under fluorescent
lighting of approximately 160 foot candles.
Such treatments to promote germination in lieu of cold stratification showed
limited success. Higher percentage germination was observed in one lot of treated
seeds of Acer floridanum than in the standard germination test. No germination
occurred in seeds soaked in water. When compared to those soaked in water two lots
of Diospyros virginiana seeds showed much higher germination percentage and earlier
germination when soaked in gibberellic acid solutions. Two lots of Halesia carolina
showed low percentage germination when soaked in gibberellic acid but no germination
when soaked in water. For one lot of Callicarpa americana seeds there was increasing
germination with increase in concentration of gibberellic acid and no germination of
those soaked in water. All seeds from three different lots (two seed crops) of
Osmanthus americanus failed to germinate under conditions specified. Symphoricarpos
orbiculatus seeds from two lots responded poorly to all treatments. Germination of
this species in the chamber was only successful in the case of one standard germi-
nation test. An additional group of S. orbiculatus seeds planted in a soil mix and
stored 60 days outside under a sawdust mulch showed similar germination percentage
of all treatments, including water soaking. Lack of response from 0. americanus and
S. orbiculatus may be attributed to failure to break down the tough seed coats, or
critical timing of treatments needed to alter cold requirements of the seeds.
III. CEMICAL PINCHING OF SELECTED ORNAMENTAL PLANTS
(Sanderson, Self and Martin)
Several experiments have been conducted on chemical pinching 
of ornamental
plants at Auburn University, the Ornamental Research Field Station in Mobile and two
commercial nurseries in Semmes, Alabama. The two chemical pinching agents, Emery
C-9 (Emery Industries', designation for Methyl Nonanoate and Offshoot-O (a mixture
of Methyl Octanoate and Methyl Decanoate manufactured 
by Proctor and Gamble), have
been evaluated at various concentrations on a number of plant species. Research on
chemical pinching of chrysanthemum has involved a comparison of various 
types-of
pinches, the influence of treatment time on the plant, the stability of the materials,
single material vs. combined sprays and the effect of spray volume and concentration.
The pinching agents were usually applied with an electric mist blower and permitted
to remain on the plant for 10 minutes before being washed off.
At concentrations of 3% and 6%, the two pinching agents produced no effect
other than burning of the foliage on Aucuba japonica, Euonymus japonicus, Gardenia
jasminoides, Ilex cornuta rotunda, Ilex vomitoria, Liustrum indicum, 
Pittosporum
tobira, Podocarpus macrophyllus and Schefflera actinophylla. 
Coleus blumei was
effectively pinched with the agents at a concentration of i2%. Excessive damage
occurred at 3% concentrations and a ,4% concentration killed some coleus. Ilex
crenata 'Heller' showed some response to a chemical pinching at concentrations of
3 to 6%. Plants were damaged at the higher concentration.
Rhododendron spy. have been quite successfully 
pinched with concentrations
of 3 to 6%. Table 1 shows the results for several 
cultivars treated at the Spring-
hill Research Station. Chemical pinching produced fewer shoots than manual 
pinching
in the cultivars 'Alaska', 'Pink Supreme' and 'Red 
Wing'. More shoots were observed
with chemical pinching than manual pinching in the cultivars 
'Chimes', 'Coral Bells',
and 'Hinodegiri'. The 6% concentration produced more shoots 
than the 3% concentration
but damaged the plant.
Table 1. Effect of Chemical Pinching Agents on the Mean Number of Lateral
Branches per Eight Inch Stem, Springhill Experiment
Cultivars Pinching treatments
EmeryC- Offshoot-0 Check
3% 6% 3% 
6% No 
Treatment
Alaska ....... . 1.5 1.9 1.9 1.7 4.2
Chimes .. .... 2.5 2.8 2.6 
2.5 2.4
Coral Bells . . . 3.9 6.1 5.0 
5.9 2.1
Hinodegiri .. . 2.9 6.5 6.5 5.9 
4.8
Pink Supreme . . . 3.5 3.4 3.2 4.8 
5.3
Red Wing . . 1.4 2.5 1.5 1.7 
4.5
Mean . . . . . .. 2.6 3.9 
3.5 3.8 3.8
Results of experiments conducted in Semmes, Alabama are presented in Table
2. Although some cultivars produced more shoots when chemically pinched, the 
mean
number of shoots for chemically pinched one-gallon plants was little different
from the shoot number for sheared plants. Considering the two-gallon plants, the
cultivars 'Evensong' and 'Hershey Red' showed a definite response to chemical pinch-
ing.
All types of chrysanthemums (cut, potted and garden) have been successfully
pinched with chemicals.
Table 2. Response of Several Azalea Cultivars of One-Gallon and Two-Gallon
Size to Chemical Pinching 1/
Mean number of breaks per shoot
Cultivar One-gallon Two-gallon
Emery Offshoot Sheared Emery Offshoot Pinch
3% 3% 3% 3% No.
Alaska. .... .... 2.5 2.7 2.7 -. ..
Coral Bells .... . 2.5 3.1 2.6 3.2 3.5 2.1
Evensong . . .... -- --- -
5.4 4.2 1.8
Hershey Red . . -- --- 3.7 3.8 1.5
Hexe ....... . . --- --- -- 1.2 2.3 1.1
Hinodegiri .... . . 28 2.9 3.4 4.5 3.9 4.2
Morning Star ..... - --- - 2.7 2.4 1.9
Pink Supreme . . 2.4 2.4 2.3 2.2 2.3 1.9
Red Wing ....... 3.0 2.2 2.5 2.4 1.8 1.1
Sweetheart Supreme 3. . 3.0 2.7 2.0 2.4 2.4 1.8
Snow . ........ --- --- --- 2.9 2.2 2.3
Mean .. ........ . 2.7 2.7 2.6 3.1 3.1 2.0
]/ One-gallon plants sprayed at Blackwell Nurseries, Inc., Semmes, Ala. Two-gallon
plants sprayed at Tom Dodd Nurseries, Inc., Semmes, Ala. The cooperation of
these two nurseries is gratefully acknowledged.
The tedious and time consuming task of pinching chrysanthemum is quickly
realized in garden chrysanthemum. These plants often require three pinches thus
multiplying the task with each pinch. A cultivar response was observed in garden
chrysanthemums,however chemical pinching produced more flowers, a shorter compact
plant, and a more desirable plant in those cultivars that did respond to chemical
pinching. The cultivars 'Rosey Nook' and 'Gemini', gave excellent responses to a
3% concentration. Other cultivars treated included 'Lawrence Blaney', 'Falcon',
'Mango', 'Millionaire', 'Yellow Joanette', 'Yellow Fujii Williams', 'Yellow Minnpink',
and 'Corvette'.
A 2 to 39
chrysanthemums.
manual pinches.
concentration, depending on the cultivar, has been used on other
Chemical pinching has produced more shoots than various 
types of
Shoot development was slower with chemical pinching than with manual
5
pinching. Low pressure, 
high volume sprays yielded 
poorer results than a full
strength mist. Reducing the 
concentration and applying a high volume 
spray in-
jured and killed plants. A mixture 
of equal parts of the two chemical 
pinching
agents was more effective in pinching than 
separate applications of the same con-
centrations. Leaving the materials on the plants 
for 15 minutes increased their
effectiveness on cv. 'Golden Yellow Princess 
Anne'. Pinching agents were found to
be quite stable. Materials refrigerated or stored at room 
temperature for 30 days
yielded pinching results equal to fresh 
made materials.
IV. UTILIZATION OF PROCESSED GARBAGE-SLUDGE 
AS A MEDIA ADDITIVE IN THE PRODUCTION
OF WOODY PlANTS IN CONTAINERS
(Sanderson, Self, Orr and Martin)
Identical experiments were 
established at Auburn University, 
Auburn, Alabama
and the Springhill Ornamental 
Horticulture Field Station, 
Mobile, Alabama to com-
pare processed garbage amended 
with raw sewage with other media 
additives in con-
tainer plant production. The 
nine media mixtures shown iTable 
3 were used to
grow the following species: 
Camellia sasanqua, Ilex cornuta 
'Burford', Ilex crenata
'Hetz', Tuniperus conferta, Rhododendron 
obtusumn japonicum and Viburnum 
burkwoodi.
The pH and soluble salts of the mixtures 
are also presented in Table 3. Spurway
analysis of processed garbage-sludge 
revealed nitrates 0 p.p.m., phosphorus 
0 p.p.m.,
potassium 20-40 p.p.m. and calcium 
100 p.p.m. Soluble salts frequently 
exceeded 80,
the toxic level. Following soil 
analysis, the pH of the nine mixtures 
was adjusted
to either 6.0 or 5.0. The 
lower pH being used on the azaleas 
and camellias. The
pH adjustments were made 
with either limestone or 
dusting sulfur. Mixtures 
adjusted
with sulfur received 2 lb. 
of gypsum per cu. yd. Superphosphate 
(0-20-0) was added
to all the mixtures at the rate 
of 2 lb. per cu. yd. Fertilization 
consisted of four
applications of 12-6-6 
analysis fertilizer with minor 
elements added (Sta-Green
supplied by the Parker Fertilizer 
Company, Sylacauga, Alabama 
and one application
of a 14-4-6 analysis fertilizer tablet during the growing season. The 12-6-6 analysis
fertilizer was applied at 
the rate of one-half level teaspoon 
per container. One 12
g. container tablet was placed 
in each container. The experiment 
was replicated four
times at each location. Experimentally, 
there were 2 locations, 4 replications, 
6
species, 5 plants per treatment 
and 9 treatments for a total 
2,160 plants. A random-
ized block design was used 
at both locations. A mean 
height, spread and dry weight
was determined for each species.
Table 3. Mean pH and Soluble 
Salts of Media Mixtures Prior 
to Adjustment _/
Media Mixture 
pH Soluble salts
Sand and Peat ......................... 
4.4 0
Sand and Garbage-Sludge ..... ... 
.............. 8.2 40
Sand, Peat and Garbage-Sludge 
............ . . .
6.2 26
Perlite, Vermiculite and Bagasse .. 
.......... ... 4.5 10
Perlite, Vermiculite and Garbage-Sludge... 
... . 8.2 42
Vermiculite and Peat ...... ............... 
. . . 4.3 5
Vermiculite and Garbage ..... 
... ............ 8.1 
44
Vermiculite, Peat and Garbage .
..... ............ 6.4 
26
/ Adjustments were made with 
either limestone or sulfur 
to produce pH 6.0 and 5.0.
Mixtures adjusted 
with sulfur received 
2 lb. of Gypsum per 
cu. yd.
2/ Equal portions of 
material were used 
in each mixture.
Observations one year after planting showed high 
soluble salts and pH of
processed garbage-sludge had made it extremely difficult to maintain 
adequate
plant nutrition. The soluble salts dropped rapidly following 
pH correction-and
culture (probably leaching). Some plants exhibited deficiency 
symptoms soon
after planting but usually recovered normal color following 
fertilization. Winter
injury killed 85% of camellias and 20% of the 
azaleas in Mobile during the first
growing season. Losses in Auburn were not as great 
with 8% of the camellias and
less than 1% of the azaleas being killed. The losses 
could not be correlated with
treatment. The foliage color of the plants in Mobile 
was not as good as that in
Auburn. Shore Junipers showed extreme chlorosis in the sand 
mixtures at Mobile.
Best leaf color appeared in the vermiculite mixtures with the bagasse mixtures
being next. Plants at Auburn did not display such great differences 
in leaf color.
Increased rainfall in Mobile may have influenced the 
fertility of the mixtures and
the results obtained.
V. COMPARISON OF PROCESSED GARBAGE, SAWDUST, AND 
PINE STRAW IN MULCHING GARDEN
CHRYSANTHEUMS 196
(Orr, Sanderson, and Martin)
Rooted cuttings of 19 varieties of Hardy Chrysanthemums 
were received from
the Fred C. Gloeckner Company and potted in 3-inch-square peat pots 
on June 21.
Plants were grown in the greenhouse until July 18, when they were 
planted in beds
in the garden at a spacing of 15" x 18". Fertilization 
in the greenhouse was
20-20-20 at 1 oz. per 4 gal. water weekly. 
Fertilization in the beds was 3 lb.
8-8-8 per 100 sq. ft. prior to planting and monthly applications 
thereafter at
the same rate. Plants received 3 soft pinches - June 28, July 18, and August 15.
Each bed was divided into 3 sections, 
lengthwise, with 4-inch aluminum lawn
edging. A 1-inch mulch was applied to each section 
using sawdust, pine straw,
and composted garbage. Comparisons were 
made on each mum variety in each mulch as
to flowering date, height, and spread of plants.
There were no differences in any of the 
three mulches in the flowering date,
height, and spread of the plants. The data 
is presented in Table 4.
VI. COMPARISON OF PROCESSED GARBAGE SAWDUST 
AND PINE STRAW IN MULCHING PETUNIAS 1967
(Sanderson, Orr and Martin)
Fifty-four petunia varieties were planted 
in a mulching study using pine straw,
sawdust, and processed garbage. The petunias 
were produced by sowing seed in February
and transplanting to peat pots in 
March. Plants were planted in beds 
on April 16,
1968. The beds were divided 
into three sections, lengthwise, 
with 4 inch aluminum
lawn edging. The mulches 
were applied on May 2 to 
a depth of approximately 
two inches.
Fertilization consisted of 3 lb. of 8-8-8 per 100 
sq. ft. incorporated prior
to planting and 3 lb. of 12-6-6 with a systemic insecticide 
(2% Di-Syston) applied
three weeks after planting.
No apparent differences were 
observed in the growth and flowering 
of the
plants with any of the mulches. 
Leaf and flower color was 
comparable in all the
mulches.
7
Table 4. Effect of Various Mulches on Mean Height Spread of Garden Chrysantherwn
-Variety Flower- Height - in. _ _Spread in.
ing Saw- Pine Gar- 
Saw- Pine Gar-
date dust straw bage dust straw bage
Cheyenne ... . .... 10/23 20.0 19.5 20.0 17.5 l,. 1$.0
Chiquita ........... 10/9 17.0 17.5 17.5 16.5 16.0 16.5
Corvette. ...... ... 10/9 18.0 17.5 17.5 16.5 16.0 16.5
Early Gold....... . 9/25 12.0 13.0 13.0 14.0 13.0 14.0
Falcon .. .......... 10/9 14.0 14.5 14.00 l1.0 1$.5 19.0
Gemini ..... .. ... .10/23 20.0 20.0 1$.0 21.0 21.0 20.0
Jessamiine Williams . .. .10/9 1$.5 .. 0 L$.0 19.5 19.5 
19.5
Lawrence Blaney . . .4 10/2 19.0 17.5 17.5 17.0 17.0. 1.5.
Mango....... .... 10/9 16.5 16.5 16.5 20.5 20.0 20
Minnehaha........ 10/9 19.5 19.0 18.5 l8.5 l8.0 1$.0
Millionaire......... ... 10/9 1$.5 19.0 18.5 
20.0 19.5 19.5
Powder River .......... 10/2 13.0 12.5 13.0 15.5 15.5 16.0
Red Desert. ....... 10/9 12.0 13.0 
12.5 15.5 13.0 15.5
Rosey Nook ... ....... 10/16.14.0 14.0 14.0 19.0 20.0 19.0
Shining Light. ...... 10/2 16.0 16.0 15.5 
16.5. 16.5 15.5
Tranquility ...... .. 10/2 16.5 16.5 17.0 17.5 17.0 17.0
Yellow Fujii Williams 10/9 17.0 17.0 .17.-0 1$,5 1$,01$,5
Yellow Joanette . 10/9 20.5 20.5 20.0 19.5 20.0 19.5
Yellow Minnpink . .. 11.0 10.5 10.5 19.0 19.0 19.0
Mean . ...... 16.5 15.9 16.,2 17.9 17.7 17.9
VII. ANNUJALS - TRIALS .196$
(Martin and Orr)
Spring flowering annuals grown in a Test Garden included. petunias, ageratum,
browallia, snapdragons,* salvia, celosia, marigolds, amaranthus, and carefree geraniums .
Seeds were furnished by. Pan-American :Seed Company, West Chicago, Illinois and. Henry
F. Mitchell, King of Prussia, Pa. Seed were sown~in February. The seedlings were
transplanted to peat' pots in March and planted 
in beds in the-garden April 16. Re-.
cords were taken June 25 on height and spread of the plants.
Some of the more outstanding and new varieties are listed: below with the
Gerfa niu -CaefeeDep alon12x12
Marigold - Orange Jubilee 22" x 30"
Petunia - Miss Blue (New) Height - 19"
Petunia - Lavender Lady (New) Height - 13"
Petunia - Rose Magic (New) Height - 16"
Petunia - Scarlet Magic (New) Height - 14"
Petunia - Lillipop (New) Height - 14"
Petunia - Pink Bells (New) Height - 15"
VIII. SOUTHERN REGIONAL MARKETING OF WOODY ORNAMENTALS - ALABAMA
(Orr and Miller)
Objective 1
The purpose of this study was to determine movement patterns and marketing
channels for woody ornamental plants and handling practices and pricing behavior
of firms that market them.
The data from the questionnaire of this objective have been analyzed by
computer and are in the process of being formulated into a publication which is
anticipated to be available to all nurserymen in the spring of 1969.
This information should serve as a basis for nurseries to analyze their
management practices and 
aid in expanded growth of 
the industry.
Objective 2
The purpose of this study is to determine the factors that influence firms
in their decisions to purchase woody ornamentals for resale.
Currently the project is concerned with which nurseries will participate in
answering the questionnaire. Preliminary questions on cards have been mailed to
retail nurseries, landscape contractors, and garden centers. The cards of respondents
to these questions will be analyzed to determine which firms will participate in
answering the final questionnaire in order to get a representative 
cross section of
the firms retailing woody ornamental plants.
The final questionnaire for Objective 2 will be completed during September
1968 and the data analyzed during the Winter 1968-69.
The results of this study should indicate the methods now being used to pur-
chase and resell woody ornamentals and to provide insight to improved marketing
techniques.