Historic note
 Title Page
 Table of Contents

Group Title: Circular - Florida Cooperative Extension Service ; 280-B
Title: Pecan production in Florida
Full Citation
Permanent Link: http://ufdc.ufl.edu/UF00072526/00001
 Material Information
Title: Pecan production in Florida
Series Title: Circular Florida Cooperative Extension Service
Physical Description: 31 p. ill. 23 cm. : ;
Language: English
Creator: Arnold, C. E
Lawrence, Fred P
Florida Cooperative Extension Service
Publisher: Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida
Place of Publication: Gainsville FL
Publication Date: 1974
Subject: Nuts -- Florida   ( lcsh )
Pecan -- Florida   ( lcsh )
Genre: non-fiction   ( marcgt )
Statement of Responsibility: C.E.Arnold, Fred P. Lawrence.
General Note: "May 1974."
General Note: Cover title.
Funding: Circular (Florida Cooperative Extension Service) ;
 Record Information
Bibliographic ID: UF00072526
Volume ID: VID00001
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: oclc - 20740426

Table of Contents
    Historic note
        Historic note
    Title Page
        Page 1
    Table of Contents
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Full Text


The publications in this collection do
not reflect current scientific knowledge
or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
research may be found on the
Electronic Data Information Source

site maintained by the Florida
Cooperative Extension Service.

Copyright 2005, Board of Trustees, University
of Florida


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BOTANY ......................- .... .. .... 3
ADAPTATION ....... ............................ 3
PLANTING THE ORCHARD ......... .... 3
Varieties ... ...... ........... .... 3
Site Selection ......... ..... ... ............- 10
Time of Planting -.................... .... 10
Selecting Trees .. .... .. .... .... 10
Soil Preparation and Tree Spacing -.......... 10
Pre-Planting Care.. .......................... 10
Transplanting .... ...................... ..... 10
Care of Young Trees .. ................... 11
Management for Pecans Alone ......... ....... 11
Management for Production of an Intercrop ..............- 11
Management for Pasture .. 12
Nitrogen ........._ ..........- ......... ..- 12
Potassium ....-- ........ ~ ... .. ...... .... 12
Phosphorus --- --.~...... ........ -- 13
Lime, Calcium and Magnesium ..... 13
Zinc .. .... ........... ... ........ 13
Manganese .........- .... ......... 14
Boron ...................... ........ ................... 14
HERBICIDES .........- ..-- ... 15
THINNING AND PRUNING ................. 16
PROPAGATION .........................- 17
Topworking Mature Trees ....................... 17
Nursery Propagation .... .. ...- .. .... 19

C. E. Arnold and Fred P. Lawrence
Assistant Horticulturist and Citriculturist


The pecan (Carya illinoensis)
is a native species found along the
lower Mississippi River Valley and
the river bottoms of Texas and
northern Mexico. This is a large
deciduous tree also cultivated ex-
tensively throughout the south.
The tree produces both pistillate
(female) and staminate (male)

flowers (Fig. 1). Pistillate flowers
are borne terminal on growth of
the current season and nuts nor-
mally appear in clusters of 2 to 8.
Staminate flowers in catkins (Fig.
2) are borne on wood of the pre-
vious season, at the base of new
shoots and sometimes on 2 year-
old shoots.

Pecan trees are found in prac- satisfactory in the southern half
tically every county in Florida. The of the peninsula but nut produc-
tion is relatively low because of
major production areas are the low because of
higher winter temperatures, high-
north and northwestern parts of er rainfall and increased disease
the state. Tree growth is often problems.

VARIETIES More than 175
varieties have been named of
which only a few are commercially
acceptable. A pecan variety should
come into bearing early, be pro-
lific, produce consistently and be
at least moderately resistant to
scab to be commercially accept-
able. Nuts should be medium to
large in size with shells that crack
easily and plump straw-colored
kernels of good flavor and quality.
Most varieties require 4 to 7
years under good orchard manage-
ment to begin bearing and 7 to 12
years to produce a commercial
Higher market prices are ob-

trained for large thin-shelled nuts
with high-quality kernels. Large
nuts are in particular demand for
the in-shell trade. However, most
pecans go to shelling plants. Con-
sequently, heavy bearing varieties
which produce small to medium-
sized nuts of good quality are in
demand. Poor-quality nuts, regard-
less of size, bring low prices and
may be difficult to sell in years of
heavy production.
All of the varieties described be-
low as well as many others are
being grown in some parts of Flor-
ida. Commercial growers should
select those which give best results
in their immediate localities and

'Excerpts in this Circular were taken from Bulletin 601 by R. H. Sharpe
and Nathan Gammon, Jr., University of Florida.

Fig. 1 "A" is pistillate (female) flower ready for pollination.
"B" is staminate (male) flower ready to release pollen.

Fig. 2 Staminate (male) flowers borne on wood of the
previous season and at the base of new shoots.


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not plant more than 3 or 4 varie-
ties. Notably scab-resistant varie-
ties should be selected for door-
yard or small orchard culture,
since these trees are likely to re-
ceive less attention as to disease
Pecan varieties, in general, are
designated as Western, those hav-
ing their origin in the western part
of the pecan belt and Eastern,
those originating from eastern
Texas eastward. It is not advisable
to plant varieties of the Western
group in humid areas, as most are
highly susceptible to pecan scab.
However, most of the Western va-
rieties produce nuts at an early
age and may be planted where a
rigorous spray program to combat
scab is followed.
Stuart is probably the most wide-
ly distributed variety throughout
the pecan belt. It is one of the
most resistant to scab, although
trees in certain areas have been
severely infected in recent years.
The tree is upright, often attain-
ing considerable height with only
a slight spread of branches. The
twigs are light gray. The leaves
are firm and not very dense.
Growth is moderate except on fer-
tile locations where annual twig
growth may be two or three feet.
Trees are often quite delayed in
quantity production but produces
rather consistently in later years.
They are moderately productive
and fairly regular in bearing on
the clay soils in northwestern
Florida with adequate nutrition.
The nuts are medium to large,
very attractive with well-defined
markings, oblong to slightly obo-
vate, and regular in shape. They
show up well in commercial pack-

ages. The shell is moderately
thick but cracks easily. The kernel
is plump and has good quality and
flavor, but breaks easily when re-
moved from the shell (Fig. 3).
Stuart is planted extensively over
northern and western Florida. It
originated in Jackson County, Mis-
Curtis is highly prized in the
eastern part of the pecan belt. The
tree begins to bear at a fairly early
age and is moderately resistant
to scab. Crops in heavy ("on")
years are sufficient to give a good
average yearly production. The
tree is somewhat dwarf, with a
slight spreading upright growth
and the upper parts of the branch-
es bend outward.
The nut is small to medium,
larger at the base and tapering to
the apex, with a slight curve to
one side (Fig. 3). The shell is thin,
cracks easily, and yields a plump
kernel of high quality and excel-
lent flavor but sprinkled with dark
specks, which do not affect the
quality on the surface. Curtis orig-
inated in Alachua County, Florida.
Desirable originated at Ocean
Springs, Mississippi and has been
quite widely disseminated by the
U. S. Department of Agriculture.
It has had only limited tests in
Florida but appears promising.
The tree is rounded with a moder-
ately open type of growth and be-
gins to bear at an early age, is
prolific, and produces quite reg-
ularly. The nuts are large, crack
easily and usually fill well. The
sides of the nuts are slightly de-
pressed and uneven (Fig. 4).
Elliott has been propagated for
more than 20 years but never
widely disseminated. It has been

grown in a few orchards in the
northern part of Walton County,
where it is prized highly, and is
now being planted across the pecan
belt and in Mexico. The tree is
vigorous but slow to attain large
size. It has a rounded symmetrical
top with numerous terminal twigs,
medium size leaves with thin leaf-
lets which are decidedly curved
and apparently resistant to scab.
The tree is fairly precocious, pro-
lific and generally a consistent
bearer. The nut is small with
a rounded base, pointed apex, par-
tial markings, plump, smooth
straw color and a medium thick
shell. It is of excellent flavor and
quality and very good for cracking
purposes (Fig. 4). Elliott origi-
nated in Santa Rosa County, Flor-
Success is subject to scab and
requires a spray program to insure
production. It should be planted
only on the heavier soils,, with an
adequate supply of plant food and
moisture, as production is variable
when these requirements are not
met. It has been planted extensive-
ly in northern and western Florida.
The tree is moderately vigorous,
with a funnel-shaped top and
branches coming out uniformly
around the trunk. It begins to pro-
duce nuts at a moderately early
age and is fairly regular and con-
sistent in bearing but tends to
overbear at times. The nut is
large, wedge-shaped, with one lobe
at the apex slightly depressed and
moderately thick shelled. It cracks
well and the kernel is plump, of
satisfactory color, and good qual-
ity and flavor when grown under
proper conditions (Fig. 5). Suc-
cess originated in Jackson County,

Mahan has been widely dissem-
inated throughout the pecan belt
since 1926. The tree is vigorous
with a symmetrical, well shaped
top and thick heavy foliage. The.
leaves have unusually large leaf-
lets. The tree is fairly precocious
and a consistent producer when
grown under suitable conditions.
It is susceptible to scab, which may
become severe when the weather
is favorable for scab development,
and will require spraying. The nut
is very large (Fig. 5), with general
shape and markings somewhat
similar to Schley. The shell is thin
so that the nut cracks easily. The
kernel is fairly plump and of good
flavor and quality. Mahan origi-
nated in Attala County, Missis-
Moneymaker is popular because
generally it is quite prolific. It is
planted in all parts of the state.
It is susceptible to scab and re-
quires spraying. The tree has an
upright, open, spreading type of
growth and usually begins to bear
at an early age, but it is not con-
sistent unless soil fertility is high
and the foliage is maintained. The
nut is medium in size, slightly
wedge-shaped, rounded with a
medium thick shell that cracks
satisfactorily (Fig. 6). The kernel
is usually plump and of good flavor
and quality. Moneymaker origi-
nated in Madison Parish, Louisi-
Schley is an outstanding variety
and probably would be the most
generally grown variety east of
the Mississippi River, if it were
not so highly susceptible to scab.
However, scab can be controlled
with sprays and the nuts usually

Fig. 3 Nuts of Stuart (left) and Curtis varieties.

Fig. 4 Nuts of Desirable (left) and Elliott varieties.

Fig. 5 Nuts of Success (left) and Mahan varieties.

Fig. 6 Nuts of Moneymaker (left) and Schley varieties.

bring a price sufficient to justify
the extra expense when trees are
maintained in a productive condi-
tion. The tree is rather vigorous
with thick foliage made up of
closely set leaves with large leaf-
lets. The twigs are grayish in color
and smooth, turning rough with
age. The buds are pointed and
brown. The tree is round-topped
with branches growing upward
and outward. It is considered by
many as the most beautiful of all
pecan varieties. The tree begins to
bear fairly early and is moderately
prolific and a regular bearer under
good management. Nuts are me-
dium to large, oblong, obovate or
irregular in outline, with opposite
sides slightly depressed. The apex
is sharp-pointed and flat. The base
is blunt. The shell is very thin,
cracking easily. The kernel is
plump, straw-colored, rich in oil
and of excellent quality and flavor
(Fig. 6). Schley originated in
Jackson County, Mississippi.
Moore is grown extensively in
Jefferson and Duval counties and
planted to a limited extent in other
counties. The tree begins to bear
at an early age and is prolific,
generally being consistent in an-
nual production. It is not very
large and inclined to produce wil-

lowy twigs which often grow out
and downward, especially on the
lower branches. It requires spray-
ing to control scab. The nut is
small to medium, elongated and
brownish with distinct dark mark-
ings at the apex reaching about
1/ of its length (Fig. 7). The shell
is of medium thickness, but cracks
easily. The kernel is easily removed
whole, fairly plump and of good
quality and flavor. Moore origi-
nated in Jefferson County, Florida.
Kennedy is widely known in
Alachua and Bradford counties. It
is similar to Curtis, although the
tree has slightly heavier foliage
and the nut is larger and more
pointed. It produces fairly well
and is susceptible to scab. The
tree is upright and of medium size,
begins to bear at a comparatively
early age, but often is inclined to
bear irregularly. Limbs often
break badly with heavy crops. The
nut is medium in size, decidedly
pointed at the apex, straw-colored
set off by distinct markings at the
apex, moderately thin shelled, and
cracks easily. The kernel is firm,
easily removed whole from the
shell, fairly plump and of good
quality (Fig. 7). Kennedy origi-
nated in Alachua County, Florida,

Fig. 7 Nuts of Moore (left) and Kennedy varieties.



Cape Fear
Harris Super

Harvest Scab
season resistance





Precocity* Ease of %
cracking Kernel










Good overlap


*Precocity refers to the age when a tree begins to bear.

A good precocious variety will normally bear

a few nuts the fourth

**With a protandrous variety, the pollen (male) is mature most years before the stigma (female) is receptive. With a pro-
togynous variety, the stigma is receptive most years before the pollen is mature. It is desirable to interplant protandrous
and protogynous varieties.

of soil is of major importance in
planting a commercial pecan or-
chard. The best soil under Florida
conditions is a .sandy loam which
is well-drained to a depth of 60 to
72 inches. Soils with less than 36
inches of well-drained soil should
be avoided. Trees growing on shal-
low soils may be damaged by
drought or excessive moisture and
thus prove to be uneconomical.
trees are planted as soon as possi-
ble after they become dormant,
preferably in late December and
January. Young trees should be
set early in the dormant season so
the root system will become estab-
lished before the'trees leaf in the
spring. Growth will then be more
vigorous than with later plantings.
varieties which are capable of pro-
ducing good yields of high quality
nuts and will require a minimum
of disease control. Nursery trees
should be in good condition and
Trees 4 to 7 feet tall are prob-
ably the best size to transplant.
They cost less than larger ones and
are less apt to die. Larger trees
take more labor to transplant and
require more post-planting care.
Older trees are often purchased by
homeowners for dooryard plant-
ing, where the increased expense
can be justified because of their
ornamental value.
TREE SPACING Soil should be
well prepared by plowing under all
vegetation and thoroughly disk-
ing. Stake off the field prior to
planting. A common spacing in

Florida is 60 feet apart each way
(12 trees per acre). Closer spac-
ings of 30 X 30 (48 trees per acre)
or 40 X 40 (27 trees per acre) are
being tried, however, on an experi-
mental basis. Removal of selected
trees or pruning will be necessary
when the trees reach maturity if
closer spacings are used. The or-
chard is generally laid out in a
square pattern with plantings on
the contour on terraced slopes.
should be purchased from a reli-
able nursery. Trees from nearby
nurseries are usually better adapt-
ed to local soil and climatic condi-
tions. Arrange with the nursery-
man to have trees dug and deliv-
ered on the same day they are to
be transplanted. Heel trees in wet
sawdust or soil if they cannot be
transplanted soon after arrival.
NEVER expose the roots to the
sun and wind even for short peri-
ods. Be sure all roots of heeled-in
trees are well covered and apply
water as needed.
to 30 inches in diameter and 24 to
36 inches deep are necessary to ac-
commodate the root systems. Mix-
tures of peat or top soil may prove
beneficial for better moisture-
holding capacity and root growth.
Remove trees from their bales or
boxes in the field. Protect the roots
from drying out. Use care in set-
ting and placing the roots and fill-
ing in the hole with soil. Place the
roots in as near a normal position
and at the same depth as in the
nursery as possible. "DO NOT
PLANT TOO DEEP. Prune bro-
ken and damaged roots and remove
1/3 to 1/2 of the top of the tree at

the time of planting. This pro-
vides a balance between the top
and roots and simplifies the prob-
lem of proper heading later.
Press the soil firmly as the hole
is filled with soil and water, leav-
ing it about as it was when the
trees were growing in the nursery.
Use about 5 gallons of water
around each tree when the hole is
3 full of soil. Make a basin about
5 feet across around the base of
the tree to serve as a water reser-
voir. Water the trees several times
if rainfall is insufficient.
highest percentage of young tree
losses is during the first summer,
usually from failure to water ade-
quately or to control weeds and
grass. Watering 2 or 3 times dur-
ing the spring may be sufficient
but much more frequent watering
may be required. Young trees

should be well enough established
after the first year to withstand a
moderate drought but may require
watering in a long dry period.
Overfertilization is a common
fault in the management of young
pecan trees. NO FERTILIZER
trees may be fertilized between
June 1 and July 1 with up to 1
pound of 8-8-8 plus minor ele-
ments. Fertilizer is spread evenly
over the soil in a circle about 7
feet in diameter. Fertilize the
trees the second year with 1 pound
of 8-8-8 in February and another
pound of 8-8-8 in early July. In-
crease applications by 1 pound for
each additional year of tree age.
Avoid late summer fertilizing since
it may stimulate a late flush of
growth which could result in seri-
ous freeze damage.


Pecans are borne on the current
season's growth, thus it is desir-
able to manage the trees to obtain
vigorous twig growth. Production
of such growth requires a high
level of soil fertility. Costs of
maintaining adequate fertility
over a period of years are more
than justified in a good pecan or-
Three rather distinct forms of
management have been developed
for pecan orchards in Florida: (1)
pecans alone, (2) intercrops and
(3) pasture. The key to successful
operation of each of these is to
maintain soil fertility high enough
to encourage good nut yields.
ALONE This system of man-

agement may consist of simply
fertilizing the trees as required
and controlling native cover as
necessary for harvest and spray
operations. Most growers mow the
entire orchard, but herbicides may
be used to keep areas under the
trees clean. Normally, a sod strip
would be left between the rows.
- This system was originally rec-
ommended as an economical way
to utilize orchard space while
bringing the pecan trees into pro-
duction. They are planted as close
to the trees as it is possible to op-
erate the farm equipment without
damaging the trunks. This prac-
tice apparently has had no adverse

effect upon the trees where the soil
is worked to a depth of not more
than 5 to 7 inches. Production of
cash intercrops in mature orchards
is limited largely to beans, sweet
corn and other vegetables which
can be grown in the early spring
before the trees leaf out. Some
grove owners lease their orchards
to other farmers for the produc-
tion of such intercrops. The quan-
tity of fertilizer the vegetable
grower guarantees to use is an im-
portant consideration in a lease ar-
rangement. Usually, the amount
used is adequate for both the vege-
table crop and the trees.
Peaches may also be intercrop-
ped with pecans since the pecans
usually start bearing about the
eighth year when the peaches are
decreasing in productivity. Cau-
tion must be used however in
choice of spray materials. For ex-
ample, basic copper is a recom-
mended fungicide for pecans but

copper sprays are toxic to peaches.
- Pecan groves have long been
used as supplementary pastures,
but has detrimental results to the
trees when fertility requirements
are neglected. Pastures in pecan
orchards can be a profitable enter-
prise with proper management
practices, which includes growing
legumes and adequate fertilization
for both pasture and trees. A few
pecan orchards have been planted
to grass pasture without legumes.
This practice is usually highly
detrimental to tree development
because the usual rate of fertiliza-
tion is not high enough. A mini-
mum fertilizer program to keep
the trees reasonably productive
with grass pasture would be an-
nual application of 600 pounds of
10-10-10 per acre plus 100 pounds
of nitrogen per acre as a supple-
mental top dressing.


Fertilization of pecans may vary
widely, depending upon the gen-
eral system of management se-
lected. Mature trees may be fer-
tilized with 10-10-10 or similar
mixed fertilizers at rates of 1000
to 1500 pounds per acre. Two-
thirds of this amount should be
applied in February and the re-
mainder in late June. Additional
elements should be added to the
fertilizer when soil analysis indi-
cates potential deficiency (see sec-
tion on Care of Young Trees for
fertilization recommendations for
young trees).
NITROGEN Deficiency of ni-
trogen causes light green foliage,
weak shoot growth and earlier fall

defoliation. Many orchards are far
below their potential yielding ca-
pacity because they are deficient
in this element. An annual nitro-
gen supply of 150 pounds of N per
acre (approximately 450 pounds of
ammonium nitrate) will meet the
requirements of the tree as long
as the trees do not have to com-
pete heavily with grasses or non-
leguminous weeds. Additional ni-
trogen will be needed when a heavy
grass is present to keep both the
trees and grass adequately sup-
plied with this nutrient.
POTASSIUM An annual ap-
plication of 80 pounds per acre of
potash (K20) will normally supply
the potassium requirements of pe-

can trees. The deficiency rarely
becomes so severe that typical
leaf scorch symptoms appear, but
it does weaken the trees so that
severe winter killing may take
PHOSPHORUS Deficiency of
this element has been described as
causing weak growth and leaf
chlorosis in pot cultures. Defi-
ciency patterns have never been
observed in Florida pecan or-
chards. Significant .increases in
yields have not been obtained in
recent years from phosphate ap-
plications in mature groves.
NESIUM Pecan growers in
Florida and other Southeastern
states have avoided the use of lime
for many years because they
feared an increase in pecan rosette
(zinc deficiency). Proper precau-
tions should be taken to guard
against the development of rosette
but the lack of zinc should not be
used as an excuse to permit gen-
eral deterioration of other factors
important to maintaining soil fer-
tility. Orchard soils should be
limed to the range of pH 5.5 to
6.0 if no leguminous cover crop is
grown and from pH 6.0 to 6.5 when
such a cover crop is used. The
pecan grower should arrange
through his county agent for a
soil test so that the proper quan-
tity of liming material can be ap-
plied. Dolomite rather than high
calcic limestone should generally
be used on sandy soils because
many of these orchards are low in
Magnesium deficiency has been
observed frequently in pecans
growing on the sandy soils and

occasionally it becomes severe
enough to cause defoliation with
subsequent reduction in yield.
Magnesium deficiency is charac-
terized by marginal yellowing of
leaves with interveinal chlorosis
and necrosis becoming more severe
in late summer.
ZINC Most Florida pecan or-
chards will need zinc sulfate on a
regular basis either as annual
sprays or 1 unit of zinc oxide
(ZnO) in the fertilizer. Rosette is
a physiological disorder of pecan
trees caused by a lack of sufficient
zinc to produce normal growth. It
is manifested by a bronzing and
crinkling of the leaflets, which
may become greatly reduced in
size and a shortening of the inter-
nodes, which gives the effect of
multiple bud development and thus
causing the appearance of a rosette
of leaves on the twigs. It may
cause twigs and eventually branch-
es to die back in severe cases.
This condition is corrected by
the application of zinc in some
form that will become available to
the tree. Two or 3 pounds of zinc
sulfate per tree spread evenly un-
der the branches is usually suf-
ficient to correct rosette or zinc
deficiency in mature trees on
sandy soils. As much as 10 pounds
per tree may be required on soils
of heavier texture. Two to 4
ounces will be sufficient for very
young trees.
Rosette may also be corrected
by direct sprays on the foliage.
Since trees respond more rapidly
to zinc when it is sprayed on the
leaves than when it is applied to
the soil, the use of a spray is par-
ticularly desirable in the case of
severe rosette. Foliage sprays

should contain 2 pounds of neutral
zinc per 100 gallons of water.
Spray applications of zinc should
be made between May 25 and June
15 for best results, although fair
results can be obtained later in the
MANGANESE A leaf de-
formity known as "mouse ear" ob-
served primarily in dooryard
plantings and in coastal areas has
been identified as manganese de-
ficiency (Fig. 8). It has little eco-
nomic importance but may be of
considerable concern to homeown-
ers whose trees occasionally are
severely injured. It is usually
found when leaf manganese levels
are less than 100 ppm. Manganese
levels in normal pecan leaves in
Florida range from 300 to over
2,000 ppm. "Mouse eared" trees
are often found near limerock

driveways, waste building mate-
rials or growing in soils that na-
turally contain shell or marl, all
situations with very high soil pH
"Mouse ear" can be corrected by
a soil application of from 2 to 10
pounds of -manganese sulfate per
tree depending on tree size and
severity of symptoms. Sulfur can
be used at the rate of 1 to 5 pounds
per tree to lower the soil pH and
increase availability of the man-
ganese. All of these materials
should be broadcast evenly to the
tree drip line.
BORON Deficiency of boron
on pecans has not been recognized
in Florida and no significant re-
sponses to boron have been ob-
tained. Normal boron content of
leaves seems to range from 10 to
90 ppm. It should be pointed out,

w _

Fig. 8 Lower leaves show "Mouse ear" symptoms.
Upper leaves are normal after manganese application.

however, that the leguminous
cover crops have a relatively high
boron requirement. Hence, it is
often necessary to include boron
in fertilizer for pecans to insure
a good cover crop. Fertilizers

which contain sufficient boron to
provide the equivalent of 10 to 15
pounds per acre of borax will pro-
vide adequate boron in most areas
where a deficiency might be en-


Chemical weed killers presently
approved for use in Florida pecan
orchards include dalapon (Dow-
pon), diuron (Karmex), trifluralin
(Treflan), and dichlobenil (Caso-
ron). Dalapon is effective in con-
trolling most perennial grasses.
Use 5 to 10 pounds of product
(Dowpon) in 20 to 50 gallons of
water per treated acre as a di-
rected broadcast spray or as a spot
treatment only to areas where
perennial grasses are established.
Add 1 or 2 quarts of an agricul-
tural surfactant per 100 gallons of
spray to assure good wetting of
grass foliage. Apply when grasses
are actively growing either in the
spring or in the fall before harvest.
Retreat once or twice at approxi-
mately 3 week intervals or as re-
growth warrants for a total of no
more than 3 applications a year.
Do not apply the last application
in the fall closer to harvest than

2 weeks before shuck split. Do not
disk or mow treated areas less
than 2 weeks after spraying. Do
not graze treated areas. Treat-
ment is most effective when used
in a program with a suitable pre-
emergence herbicide such as diu-
ron at 2 to 4 pounds product (Kar-
mex) per treated acre.
Trifluralin and dichlobenil con-
trol a broad spectrum of weeds but
must be incorporated (disk, roto-
tiller, etc.) into the soil immedi-
ately after application. Use 2 to
4 pints of Treflan or 8 to 12 pounds
of Casoron W-50 per treated acre
as a broadcast spray.
Additional herbicides are ex-
pected to be approved for pecans
within the next year. Consult the
Florida Cooperative Extension
Service for current herbicide rec-
ommendations. Carefully read the
label on all products before using.


A number of orchards in the
pecan belt of Florida have been
neglected to such an extent that
they are liabilities rather than as-
sets. Some of them can be re-
claimed for profitable production
by proper fertilization and man-
agement. Selection of an orchard
for rejuvenation implies that the
grower will first determine wheth-
er there is a reasonable chance
that it can be made productive.

The soil must be examined to de-
termine that there is ample light-
textured soil above the clay and
that hardpans, claypans or high
water table are not present. Trees
should be checked' to be certain
that they are of varieties known
to produce satisfactory crops in
the area. Varieties and soil are
the two most important factors in
determining whether rejuvenation
will be successful.

Trees can be rejuvenated by ini-
tiating a regular orchard manage-
ment program but it must be re-
membered that soils in a neglected
orchard may be far below a pro-
ductive level of fertility. It may
be desirable to use extra fertilizer
to overcome the deficiency in fer-
tility and re-establish rapid vigor-
ous growth as quickly as possible.
Neglected trees with a trunk cir-
cumference of 2 to 3 feet should
be fertilized the first year with 8
to 10 pounds of nitrogen (24 to 30
pounds of ammonium nitrate) and
4 or 5 pounds of potash (7 to 10
pounds of muriate of potash) per
tree. This should be broadcast un-
der the branch spread of the tree.
The best time for this application
is between December 15 and Feb-
ruary 1. Neglected orchards are of-
ten zinc deficient, thus it would be
well to apply 3 pounds of zinc sul-
fate per tree at the same time.
Trees of larger or smaller trunk
circumference should be fertilized
at proportionately heavier or light-

er rates. Standard management and
fertilization practices may usually
be followed after the first year in
an orchard undergoing rejuvena-
tion. Above average rates of fer-
tilization may be continued in
some orchards, however, through
the second and possibly the third
Dead branches should be pruned
out as far as feasible together with
other branches as necessary to aid
in the development of well-branch-
ed symmetrical trees. Steps should
also be taken early in the rejuve-
nation program to free the tree of
excessive quantities of moss or
Trees of unproductive varieties
may be cut out to provide more
space for remaining trees or top-
worked to better varieties. Top-
working should be delayed until
growth becomes vigorous because
the percentage of success from
grafts or buds is quite low on trees
in poor condition.


Spanish moss shades and re-
tards growth when trees become
heavily laden. Moss is commonly
killed during the dormant period
by a thorough wetting with a
spray of 4 to 6 pounds of neutral

copper in 100 gallons of water. The
dead moss will hang in the trees
for some time but will eventually
be blown out. If the moss is hang-
ing in heavy, thick masses, a sec-
ond application may be required
for a complete kill.


Growth and production will be
reduced and disease and insect
problems will increase when trees
have attained large size and are
crowding each other in the or-
chard. It is advisable to provide
more space under such conditions
by cutting out trees in alternate

diagonal rows or by reducing the
size of the tops of the trees. This
can be done by cutting back trees
in alternate rows by the same
method that would be used in top-
working. After a new top has been
grown sufficiently to bear nuts on
these cut back trees, the remaining

trees can be cut back in the same
manner. This will not eliminate
any of the trees, but will reduce
the size of the top to a point where
there is room for further develop-
ment. It will require 10 to 15 years
for the new tops to attain size that
will cause any serious crowding.
Pecan trees normally require
little pruning, except to thin, re-
juvenate or remove crossed-over,
broken or dead branches. Some

growers are rather severely prun-
ing large mature trees to rejuve-
nate them.
Undesirable branches should be
cut close to laterals or to the main
trunk to eliminate projecting
stubs. It is important that branch-
es be cut properly, so wounds will
callus rapidly and thus reducing
infection by wood-decaying organ-


TREES Trees of undesirable
seedlings and varieties can be
changed to a desired type by top-
working. Either budding or graft-
ing can be employed, but patch
budding is used by most growers.
Cleft grafting is done during the
dormant season, usually from late
December to the middle of Febru-
ary. Bark grafting is done in April
and patch budding in the summer
months when the trees are in
Cleft Grafting Branches
should be cut back to 4 inches in
diameter or a little less. The en-
tire cut surface should be covered
with grafting wax after scions
have been inserted. It is often ad-
visable to tie in the scion with cord
or budding tape so there will be no
danger of the stock pulling away
and preventing a union. It is im-
portant that the cambial layers of
both stock and scion match. Trees
which were grafted can be budded
during the summer if the former
scions fail to live.
Inlay Bark Graft Method -
Scionwood for inlay bark grafts
should be cut. in late February
from strong 1 or 2-year-old shoots

in 12-inch lengths and stored at
32 to 40F in moist sawdust, peat
or sphagnum to keep it from dry-
ing out. Grafts are placed in 2 to
4 inch diameter limbs during April
using the methods illustrated in
Fig. 9. Grafting should be delayed
until about the time pollen sheds
if limbs bleed badly. Scions are
usually cut 5 to 6 inches long with
a sloping cut about 1% inches long
at the basal end. This is placed
against the limb and outline cuts
are made through the bark or the
stock. The bark is then removed
and the scion fitted snugly into the
groove. Two small nails (%. to 7/A
inch long) are driven through the
grafts to hold them firmly in place
in the limb with care not to split
or injure the scion. All cut sur-
faces are coated with grafting
wax. Alternatively, the graft and
stock may be covered with highly
reflective aluminum foil which
greatly reduces the temperature
around the graft with a slit to let
the scions protrude. A plastic bag
is then pulled down over the stock
covering the foil and tied in place
to maintain high humidity.
After-care is similar to that for
other methods of grafting. Suck-



Fig. 9 Inlay bark graft method.

A. Pare down the rough, scaly portion of the bark to provide a smooth
surface for marking the outline of the scion.

B. Lay the beveled side of the scion against the pared place on the stock.
With the point of a knife, cut through the bark of the stock along each
side and across the bottom of the scion.

C. Remove the patch of bark from the stock and place the scion in the space.

D. Nail the scion in place.

E. In the same manner, place another scion on the opposite side of the stock.

F. Cover all cut surfaces with grafting wax or a tree-healing compound.

ers are rubbed off and undesirable
limbs of the stock gradually re-
moved over a 1 or 2 year period.
One scion should be cut back about
1/ the way the following winter if
both scions on a limb grow.
Budding Trees to be budded
are cut back during the dormant
season, leaving several of the
branches intact to insure proper
growth until the new buds are es-
tablished. Small trees not more
than 4 to 6 inches in trunk diam-
eter may be safely trimmed to a
single stub. Trees larger than 6
inches in diameter are pruned to
leave branches 4 to 6 inches in
Shoots will grow in the spring
where the branches have been cut
off. These will be large enough to
bud by July but the work can be
done up to the first of September.
Ring and patch methods are used
(Details are given in the following
section on Nursery Propagation).
It will be necessary to thin out un-
budded shoots after scion growth
starts. Part of these may be left
for protection but they should be
cut back to about 1/ of their
length during the year following
budding. Most of the scions will
not begin growth until the spring
following their insertion but some
type of support to prevent break-
age later may be necessary. Shoots
with live scions are cut back to
just above the bud before growth
starts and the wrap may then be
removed. However, the wrap may
be removed earlier if the tie binds
the stock so tightly as to create a
constriction and prevent normal
growth. This will be indicated by
a swelling which will develop on
the stock above the bud.

Part of the original branches
that were left on the trees can be
removed by the end of the second
year and the remainder removed
the third year if a good proportion
of the scions grow well. The same
procedure should be followed when
trees are topworked by grafting.
Well developed tops can be de-
veloped by topworking if care is
exercised in properly distributing
the scions over the tree. The new
top develops rapidly and will pro-
duce nuts in 2 to 4 years, depend-
ing upon the variety. However,
quantity production should not be
expected before the scions are 5
to 7 years old.
Production of pecan trees for
planting orchards is a highly spe-
cialized business which requires
capital and skill. Pecan seedlings
are the stock on which varieties
are worked in the nursery. The
stock is generally grown from
small to medium-sized nuts pro-
duced by vigorous, thrifty trees
which may be seedlings or varie-
Seedlings grown from nuts of
scab-susceptible varieties or from
nuts of seedling trees from the
West often will themselves be
highly susceptible to scab. Nuts
from trees of Curtis are preferred
by a number of Florida nursery-
men because they germinate well
and produce uniform stocks.
Soils with a sandy to sandy loam
texture are preferred for growth
of nursery stock. However, deep,
well-aerated soils are not as im-
portant as for trees being set in
the permanent orchard. In fact,
some nurserymen claim that soils
with a mottled heavy-textured

layer at a depth of 18 to 24 inches
are particularly desirable for nurs-
ery trees since such soil conditions
prevent the development of a deep
tap root and encourage the devel-
opment of extensive lateral roots.
It is easier to dig a higher per-
centage of roots in such soils and
the chance of tree survival after
transplanting will be improved.
Planting The Nuts Nuts
should be planted in the fall as
soon after maturity as possible.
Nuts may be stratified and plant-
ed in the field later if losses from
rodents are likely to be excessive.
Stratification may be done in a
well-drained location under a shed
or in the open by spreading nuts
and sand in alternate layers about
2 inches thick, with a top covering
of about 8 inches of sand or soil.
Nuts generally are sown in the
field, however, without stratifica-
tion. Sowing should be completed
by December 15 if possible. Nuts
kept at room temperature until
January or February should be
soaked for 36 to 72 hours before
sowing. Soil in the seedbed is
worked into a good state of culti-
vation, after which furrows about
31/2 to 4 feet apart are opened with
a narrow plow to a depth of 4 to
6 inches. Nuts are then dropped
4 to 6 inches apart in each furrow
and covered with a plow to a depth
of about 4 inches. The crust of the
soil should be broken in the early
spring as the small seedlings begin
to emerge. Planting machines are
available but are not generally
Fertilization of Nursery Stock -
Well-developed, vigorous seedlings
which will result in a higher per-
centage of success from the bud-

ding or grafting operation and a
higher percentage of marketable
trees are produced with a well-
defined and maintained fertilizer
program. A heavy tonnage of
summer leguminous cover crop
worked into the soil prior to sow-
ing will prove profitable. New land
or land that has not been fertilized
in recent years should have 500
to 800 lbs. per acre of 6-6-6 or 8-8-8
broadcast over it and worked thor-
oughly into the soil before nuts
are sown. This may not be neces-
sary on land that had been pre-
viously fertilized for other crops.
A 6-6-6 or 8-8-8 fertilizer applied
at the rate of about 500 lbs. per
acre in bands at the time of sowing
or in the spring shortly after the
young shoots appear will supply
the young seedlings with adequate
nutrition for their early stages of
growth. The application may be
repeated in June or July, or am-
monium nitrate at 100 to 150 lbs.
per acre may be used if additional
growth stimulation seems desir-
able the first year. Two applica-
tions of 6-6-6 or 8-8-8 at 500 lbs.
per acre should be made in Febru-
ary, and in June or July of the sec-
ond year. Ammonium nitrate may
be substituted for the June or July
application. Seedlings are usually
grafted at the end of the second
year. A fertilizer program similar
to that recommended for the two-
year-old seedlings should be suffi-
cient to produce a good size grafted
tree. More growth can be encour-
aged if necessary by increasing the
amount of fertilizer, especially ni-
trogen, the third year. Application
of fertilizer after the end of July
is not recommended, as the stim-
ulation of late growth may result

in formation of wood immature at
digging time.
Budding Annular, ring, and
patch are the methods of budding
used. Seedlings are large enough
to bud the second year. Budding
is begun just as early as mature
buds are present, which is about
June 15 to July 1, and may con-
tinue to September. The bark of
buds and stocks generally unite in
3 or 4 weeks, at which time the
wrap may be removed. The wraps
can be left on if they are not bind-
ing until late winter when the
stocks are cut back to just above
the scion. Seedling shoots will
grow along with the scion and
these must be removed. Scions
will require staking for several
months to give them support.
Ring Budding was formerly the
principal method used but has been
largely superseded by the patch
bud. It can be done any time dur-
ing the growing season when the
bark will slip freely.
A similar ring of bark contain-
ing the bud is cut with the same
knife from a budstick of the same
diameter and is placed where the
ring was removed from the stock.
The scion must not be removed
after it has been set in place. It
is bound firmly in place with plas-
tic budding tape wound to cover.
all cuts. Tying is important and
must be done properly, as careless-
ness in this operation is often the
cause of failure.
Patch Budding is a modified
form of ring budding which is also
done when the bark will slip. The
details in making the cut and in-
serting the bud are similar (Fig.
10). The main difference is that a

square or rectangular patch of
bark is removed from the stock
and an identical patch with a bud
in the center is removed from the
stick of budwood. Sticks of bud-
wood smaller than the stocks can
be utilized. The work should be
done rapidly to prevent drying out
of the tissues. The patch is wrap-
ped as described for ring budding.
Grafting Seedlings too small
to bud during the second summer
are grafted the following winter,
although some year-old seedlings
may be large enough to graft at
the end of the first season. The
whip and tongue graft (Fig. 11)
is used almost exclusively, the
scions inserted just below soil sur-
face. A cleft or side graft is used
when old stocks an inch or more in
diameter are to be worked. The
seedlings are barred off with a
small turn plow ahd the remaining
soil removed from the stock with
hand rakes. The part to receive
the scions is then rubbed with a
piece of burlap. January and
February are generally the best
months for grafting. Scions are
inserted and tied in place with
wax cord after which the soil is
pulled up around the grafts as
soon as possible for protection and
to prevent drying out. The fur-
rows are leveled to leave only the
top bud of the scion showing above
ground level. Fertilizers, if need-
ed, are applied just before the
seedlings are grafted. It is not
necessary to upwrap the grafts. In
the spring there will be numerous
shoots forced from the stock and
these will have to be removed,
leaving only the scions. Most of
the trees should be well developed
by fall and ready for digging.


Fig. 10 Patch budding pecans.

A. Make 2 parallel cuts extending halfway around the stock with a double-
blade knife. A single vertical cut is made at one side connecting the
parallel cuts. Similar parallel cuts are made above and below the desired
bud on the budstick. Then 2 vertical cuts are made so that the bark patch
with the bud can be removed from the budstick.

B. Raise the flap of bark on the stock.

C. Fit the bud snugly against the one cut side of the stock and tear off the
flap of bark on the other side so that it slightly overlaps the bud patch.

D. Wrap the patch with a rubber budding strip or budding tape.

E. Wrapping completed

F. Growth of patch bud.



Fig. 11 Whip grafting pecans.

A. Select a scion which closely corresponds to the
grafted. Cut the scion 4 to 6 inches in length. S
well-developed buds.

B. Make a diagonal cut 11/2 to 2 inches in length al
Make a diagonal cut the same length on the sto.
straight and smooth.

C. Make a cleft cut down the stock. The cut shou
length and one-third of the distance down from the

D. Make the same type of cleft cut in the scion.

E. Place scion on stock, interlocking the cleft cuts and
layers of stock and scion on one side of the graft.

F. Using a rubber budding strip or grafting tape, star
the graft cuts and wrap in an overlapping manner t
graft cuts.

G. Wrapping secures the scion and stock together and

H. Whip grafted tree.

size of the stock to be
cion should have 2 or 3

t the base of the scion.
ck. All cuts should be

Ild be about % inch in
tip of the diagonal cut.

I matching the cambium

t just below the area of
:o a point just about the

prevents drying out.




W. J. French and S. S. Fluker1

Disease and insects are often the
limiting factors in the production
of pecans in Florida. The nut re-
quires about 7 months to develop
and during that time is subject to
attack by a variety of pests. A
good disease and insect control
program is important, not only in
protecting the maturing crop, but
it is essential to the production of
high yields year after year. Trees
which are prematurely defoliated
by insects, mites, and diseases fre-
quently set a light crop the follow-
ing year. Although today's pecan
grower is fortunate to have effec-
tive fungicides, insecticides, 'and
improved spray equipment avail-
able to him, spraying for pest con-
trol is not an easy job. It requires
attention to many details that on
the surface may seem unimpor-
tant. Perhaps the three most im-
portant factors in a spray program
are timing, coverage, and rate.-.
STiming Pecan diseases, such
as scab, must be prevented by pro-
viding a protective covering of
fungicide over all susceptible tis-
sue from theAtime the first leaves
unfold until the nut is developed.
If the disease becomes established
on young foliage it is more difficult
to prevent infection on the nuts
during the remainder of the sea-
son. Some insects such as nut
casebearer, pecan weevil, and hick-
ory shuckworm occur in orchards
at particular and somewhat pre-
dictable times. Timing of sprays
for control of these insects is very
important and each grower should
'Assistant Plant Pathologist and
search Center, Monticello, Florid

learn to recognize the vulnerable
stages of these insects and time
his sprays accordingly. Excessive
use of insecticides should be avoid-
ed as it may create insect problems
that otherwise would not exist, as
well as adding to the pollution of
our environment.
Coverage In applying spray
materials, all leaves, twigs, and
nuts should be covered. Hydraulic
machines are designed to use large
volumes of water to carry the
chemicals to the trees. Sprays
should be applied until water runs
off leaves in the upper portion of
the tree. Do not attempt to con-
centrate or use low volume sprays
with hydraulic equipment (Table
IV). Air blast and mist blowers
are designed for low volume ap-
plication. Air blast equipment
should be adjusted before the
spray season begins to deliver the
desired volume of spray in the
proper pattern as is dictated by
tree size. Consult instruction man-
uals or spray machine represent-
ative for advice on correct place-
ment of spray nozzles. Remember,
when spraying with air blast
sprayers, the pesticide is carried
to the tree in a small volume of
water which is diluted by a larger
volume of air. Too fast a rate of
travel will result in insufficient
coverage where the trees are not
filled with spray-laden air. Rate of
travel should not exceed 2.5 miles
per hour. A machine with too
small an air capacity will not re-
place the air contained in the tree
Assistant Entomologist, Agricultural Re-

with spray-ladened air, thus poor
coverage results. Small to medium
sized trees can be row sprayed
while very large trees should be
Rates Fungicides and insecti-
cides are recommended at specific
rates of application which have
been found to be effective and non-
phytotoxic under Florida condi-
tions. It is, therefore, very impor-
tant to 1. Know required rate of
chemical per tree. 2. Calculate the
gallons of spray per tree the ma-
chine will deliver at a given rate
of travel. 3. Calculate the amount
of chemical to add per tank. Ex-
ample: Du-Ter is recommended at
0.08 pounds of 47.5% formulation
per tree. If 10 trees are sprayed
per 100 gallons of water then 10
times 0.08 equals 0.8 pounds of

Du-Ter required per 100 gallons or
4 pounds per 500 gallon tank.
The following spray schedule
(Table 1) will give commercial
control of important disease and
insect pests. The schedule is de-
signed for scab susceptible varie-
ties. Scab resistant varieties are
susceptible to other leaf spot dis-
eases and should be sprayed with
fungicides two or three times dur-
ing the summer. Where rosette is
present, use a spray of neutral
zinc (2 pounds) or zinc sulphate (2
pounds of 65%). Zinc sulphate is
very corrosive and will rust ma-
chinery. It must be washed out
with soap and water after use.
Foliar nutrient sprays should be
applied separately; do not mix
with fungicides or insecticides.


Parathion, EPN, and Guthion
are especially toxic to man and
should be applied only to commer-
cial pecans by properly trained
and equipped operators. Read the
entire label before opening any
pesticide container and heed all
cautions and warnings. Store pes-
ticides in original labeled contain-

ers out of reach of children, pets,
livestock, under lock and key. Dis-
pose of left-over spray materials
and all empty containers promptly
and safely. Follow the recommend-
ed dosage and waiting periods to
avoid excess residues and injury
to plants and animals. Avoid drift
of pesticides to adjacent areas.

(Approx. date for CONTROL For rates see
north Florida) Table II


1. 1st prepollination Scab Du-Ter or Cyprex Do not use Cyprex on
spray: When leaves Moore or Van Deman Var.
first show green. Leaf- Do not graze livestock
case in treated groves except
Approx. April 1 bearer where Malathion or Bor-
deaux are used alone.
(If a spray program was
not followed last year
add an insecticide to
control over-wintering
leaf and nut casebearer.)
2. 2nd prepollination Scab Increase gallonage per
spray: When leaves tree as the foliage
are half grown. Downy grows. Wettable powders
Spot such as Du-Ter are some-
Approx. April 15 Du-Ter or Cyprex times physically incom-
Nursery patible with emulsifi-
blight able concentrates. Check
compatibility of Du-Ter
with EC insecticides
before mixing large
3. 1st cover spray: Scab Du-Ter or Cyprex Proper timing for nut
When nuts are casebearer is very im-
1a" long. Powdery Add sulphur to Du- portant. Dimethoate
mildew Ter or Cyprex or is effective principal-
Approx. May 1 use Bordeaux alone. ly against aphids. Bor-
Nut deaux is not compatible
case- 1. Thiodan or with any of the other
bearer 2. Parathion or materials listed.
3. EPN or
4. Guthion or
5. Malathion



Any of the above.

Dimethoate or any
of the above.


TABLE I continued
NO. (Approx. date for CONTROL For rates see
north Florida) Table II
4. 2nd cover spray: Scab If weather is rainy,
Three weeks apply fungicide at two-
after No. 3. Powdery See 1st week intervals or in-
mildew cover spray crease by 2.
Approx. May 21 Aphids

5. Scab Begin checking small nuts
3rd cover spray: Downy spot for shuckworm damage. See
Three weeks Brown leaf 4th cover spray for recom-
after No. 4. spot mendation.
Powdery See 1st
Approx. mid-June mildew cover spray
6. 4th cover snrav: Scab Ar.r I sn.. An i +;A

First or second
week in July.



See 1st
cover spray

ppy, J -rcu au Illlr
shuckworm sprays at two
week intervals.

Guthion, EPN, or Parathion

7. 5th cover spray:
Last week in July
or first week in

6th cover spray:
Mid-August to
1st week in Sept.

Downy spot
Brown leaf

Downy spot
Brown leaf

'For scab-resistant varieties delete

See 1st
cover spray

Apply EPN for pecan weevils
when three or four adult
weevils can be jarred from
tree. Repeat application
in three weeks.

Guthion, EPN, or Parathion

See 1st
cover spray

Do not apply after shucks
start to open. If rainy
weather conditions exist,
it may be necessary to
apply 7th cover spray.

Parathion or
EPN, Guthion, or Parathion


fungicide from all but sprays No. 3 and 6.

S 8.


Gallons of spray applied per medium sized tree
Chemical 20 10 6.66 5 4 2.5 2
Formulation (Dilute) (2x) (3x) (4x) (5x) (8x) (10x)

per tree Pounds of wettable powder per 100 gallons of water
Du-Ter 0.08 0.4 0.8 1.1 1.6 2.0 3.2 4.0
47.5% WP
Cyprex 0.20 1 2 2.7 4 5 8 10
65% WP
Sulfur or
Ivalathion 0.60 3 6 9 12 15 24 30
25% WP
Parathion 0.40 2 4 6 8 10 16 20
15% WP
b/o v P or 0.40 1 2 3 4 5 8 10
EPN 50% WP
Thiodan 50% WP 0.40 2 4 6 8 10 16 20
Bordeaux Mixture
(copper suiplrate .8-.2 4-1 8-2 *
and lime)

Ounces Ounces of emulsifiable concentrate
per tree per 100 gallons of water
2 lo/gal EC 4 20 40 60 80 100 160 200
or Malathion
5 lb/gal EC
EPN 5 lb/gal EC 2.5 12.5 25 37.5 50 62.5 100 125
2.67 lb/gal EC 3.2 16 32 48 64 80 128 160
(DeFend or Cygon)
Thiodan 9.6 48 96 144 192 240 384 480
2 lb/gal EC
EPN 2 lb/gal EC 6.4 32 64 96 128 160 256 320
or Guthion
2 lb/gal EC

473 milliliters
2 pts.
4 qts. = 8 pts.

.1 lb. = 1.6 oz.
.4 lb. = 6.4 oz.
.8 lb. = 12.8 oz.

'These figures are for medium size (25-35 ft.) trees. For larger trees multiply
either the amount of pesticide formulation per 100 gallons or gallons per tree by
1.25. For smaller trees multiply either gallons per tree or amount of pesticide
formulation by .75.
*Low volume application of Bordeaux mixture is not recommended.

1 pint
1 qt.
1 gal.
1 oz.
1 lb.

= 16 oz.
= 32 oz.
= 128 oz.
= approx.
= 16 oz.

EPN 0.5 Do not apply within 21 days of harvest.
Do not graze meat or dairy animals in
treated orchards.
Guthion Extended* Do not apply after shucks begin to open.
Do not graze livestock in treated orchards
within 21 days after treatment.
Malathion 8.0 No time limitations.
Parathion Extended* Do not apply within 15 days of harvest
or after shucks open.
Do not graze meat or dairy animals in
treated orchards.
Bordeaux Mixture Exempt No time limitations.
Du-Ter 0.05 Limit: 6.5 lbs of 47.5% formulation/acre.
Do not apply after shucks start to open.
Do not graze livestock in treated orchards.
Cyprex 0.3 Limit: 7.0 lbs. of 65.0% formulation/acre.
Do not apply after shucks start to open.
Do not graze meat or dairy animals in
treated orchards.
Sulfur Safe No time limitations.
Thiodan 0.2 Do not apply after shucks begin to open.
Do not graze meat or dairy animals in
treated orchards.
Dimethoate 0.1 Do not apply within 21 days of harvest.
Apply only with ground equipment. Do
not graze livestock in treated orchards.
* Indicates that action is being taken to acquire data to petition for a tolerance.


Small Medium Large
(Under 25 feet) (25-35 feet) (over 35 feet)
Hydraulic 15 20 30
Air blast 4 10 5 15 7/2 30
Mist blower 3 4 5
Airplane 11% 2 21/2
For additional information regarding the control of insects and diseases, ask your
County Extension Director for the latest recommendations which are issued annually
by the Florida Agricultural Experiment Station.

This public document was promulgated at an
annual cost of $1,381.35, or .1381 cents per copy
to inform growers on pecan production.

(Acts of May 8 and June 30, 1914)
Cooperative Extension Service, IFAS, University of Florida
and United States Department of Agriculture, Cooperating
Joe N. Busby, Dean

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