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 Table of Contents
 Pesticide potpourri
 Gypsum for peanuts
 Checking tobacco barns for heat...
 Curing tobacco
 Replacement fertilization...
 Pesticides registrations and...
 Publications


FLAG IFAS PALMM UF



Agronomy notes
ALL VOLUMES CITATION SEARCH THUMBNAILS PAGE IMAGE ZOOMABLE
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00066352/00035
 Material Information
Title: Agronomy notes
Uniform Title: Agronomy notes (Gainesville, Fl.)
Physical Description: v. : ill. ; 28 cm.
Language: English
Creator: Florida Cooperative Extension Service
Publisher: Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida.
Place of Publication: Gainesville
Creation Date: June 2003
 Subjects
Subjects / Keywords: Crops and soils -- Florida   ( lcsh )
Crop yields -- Florida   ( lcsh )
Agriculture -- Florida   ( lcsh )
Agronomy -- Florida   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
periodical   ( marcgt )
serial   ( sobekcm )
 Notes
Statement of Responsibility: Florida Cooperative Extension Service, University of Florida, Institute of Food and Agricultural Sciences.
General Note: Description based on: January 1971; title from caption.
Funding: Florida Historical Agriculture and Rural Life
 Record Information
Source Institution: Marston Science Library, George A. Smathers Libraries, University of Florida
Holding Location: Florida Agricultural Experiment Station, Florida Cooperative Extension Service, Florida Department of Agriculture and Consumer Services, and the Engineering and Industrial Experiment Station; Institute for Food and Agricultural Services (IFAS), University of Florida
Rights Management: All rights reserved, Board of Trustees of the University of Florida
Resource Identifier: aleph - 000956365
notis - AER9014
System ID: UF00066352:00035

Table of Contents
    Table of Contents
        Page 1
    Pesticide potpourri
        Page 2
    Gypsum for peanuts
        Page 2
    Checking tobacco barns for heat exchange leaks
        Page 2
    Curing tobacco
        Page 3
    Replacement fertilization for tobacco
        Page 3
    Pesticides registrations and actions
        Page 4
    Publications
        Page 4
        Page 5
Full Text






AGRONOMY
UNIVERSITY OF
FLORIDA NOTES
IFAS EXTENSION


June, 2003


DATES TO REMEMBER
July 7 Perennial Peanut Field Day Moultrie, GA
July 8 Agronomy Weed Science Field Day (Deep South Weed Tour) Jay
Research Farm
Sept. 3-4 17h Annual Georgia Peanut Tour Macon, GA
Sept. 5 Row Crop Field Day Jay Research Farm
Aug. 28 Peanut Field Day Marianna



IN THIS ISSUE


COTTON
Pesticide Potpourri ............... .................... ......... 2

PEANUTS
Gypsumfor Peanuts ............... ........................... 2

TOBACCO
Checking Tobacco Barns for Heat Exchanger Leaks ..................... 2
C during T tobacco ..................................... .......... 3
Replacement Fertilization for Tobacco ................................ 3

MISCELLANEOUS
Pesticide Registrations and Actions .................................. 4
Publications ........................................ ............ 4


The Institute of Food and Agricultural Sciences (IFAS) is an Equal Employment Opportunity Affirmative Action Employer authorized to provide
research, educational information and other services only to individuals and institutions that function without regard to race, color, sex, age,
handicap or national origin. For information on obtaining other extension publications, contact your county Cooperative Extension Office. Florida
Cooperative Extension Service / Institute of Food and Agricultural Sciences / University ofFlorida / Christine Taylor Waddill, Director.









Pesticide Potpourri

Nearly a decade after it was discovered, an
exotoxin derived from the Bacillus
thuringiensis bacterium is on the verge of
gaining commercial approval in the U.S. for
incorporation into transgenic cotton plants as
another pest insect management tool. VIP
cotton (for vegetative insecticidal protein) is
said to offer broad spectrum, full season
control of major lepidopteran pests, and
potentially Spodoptera species. However,
selected field testing in 2002 produced mixed
results with a report of excellent control of
several key insects, but inadequate impact on
others. Structurally, functionally, and
biochemically VIP is different from B.t.
delta-endotoxins. When pest insect larvae
feed on VIP cotton plants, the critical protein
is ingested, causing the larvae to stop feeding
and expire. Further field testing is
anticipated during 2003, perhaps including
head-to-head comparative trials between
current B.t.-cotton and VIP cotton.
(Syngenta Crop Protection via IPMnet,
4/25/03).

MAM

Gypsum for Peanuts

If soil tests indicate a need, or if peanuts are
being grown for seed purposes or are of the
virginia market-type, apply gypsum by the
time plants are blooming. Gypsum is a
readily available source of calcium, which is
needed as the pegs enter the soil to help
insure good pod fill and reduce some soil-
bome pod diseases. Gypsum is needed for
seed peanuts to insure good germination and
vigor, and large seeded peanuts usually show
a response to gypsum. In addition, gypsum
helps insure brighter hulls, which is
important for the in-shell trade. Since little
calcium taken up by the roots is moved to
the pegs and pods, uptake must be by these


structures. Gypsum recommendations are
for 400 pounds per acre for runner peanuts
and 800 pounds per acre for large-seeded
peanuts, applied in an 18-inch band over the
row. These rates are based on bagged, dry
gypsum because of consistency in purity and
moisture content. However most gypsum is
applied broadcast and is derived from the
manufacture of super-phosphate, or from
electrical power plants where gypsum is
formed as a by-product of pollution control
methods. Since this gypsum is broadcast and
contains varying amounts of moisture, a ton
per acre is usually used for large-seeded
peanuts and about half that for runner
peanuts.

EBW

Checking Tobacco Barns for Heat
Exchanger Leaks

All tobacco curing barns have been
converted from direct combustion units to
the heat exchanger system. Not allowing the
combustion gases to pass through the
tobacco has greatly reduced the level of
tobacco- specific nitrosamines (TSNA) in the
cured leaf. The nitrogen gases created by
combustion reacted with the tobacco to form
TSNA. However cracks or leaks may
develop in the heat exchanger and again
allow combustion gases to enter the curing
chamber, thereby allowing TSNA to form.
No reliable and inexpensive method of
measuring nitrogen oxides is available, so
carbon dioxide meters have become the best
method of determining if there are cracks or
leaks in the heat exchanger. County agents
have access to such a meter and can test
barns for growers. These checks should be
made before tobacco is placed in the barn for
curing.

EBW









Pesticide Potpourri

Nearly a decade after it was discovered, an
exotoxin derived from the Bacillus
thuringiensis bacterium is on the verge of
gaining commercial approval in the U.S. for
incorporation into transgenic cotton plants as
another pest insect management tool. VIP
cotton (for vegetative insecticidal protein) is
said to offer broad spectrum, full season
control of major lepidopteran pests, and
potentially Spodoptera species. However,
selected field testing in 2002 produced mixed
results with a report of excellent control of
several key insects, but inadequate impact on
others. Structurally, functionally, and
biochemically VIP is different from B.t.
delta-endotoxins. When pest insect larvae
feed on VIP cotton plants, the critical protein
is ingested, causing the larvae to stop feeding
and expire. Further field testing is
anticipated during 2003, perhaps including
head-to-head comparative trials between
current B.t.-cotton and VIP cotton.
(Syngenta Crop Protection via IPMnet,
4/25/03).

MAM

Gypsum for Peanuts

If soil tests indicate a need, or if peanuts are
being grown for seed purposes or are of the
virginia market-type, apply gypsum by the
time plants are blooming. Gypsum is a
readily available source of calcium, which is
needed as the pegs enter the soil to help
insure good pod fill and reduce some soil-
bome pod diseases. Gypsum is needed for
seed peanuts to insure good germination and
vigor, and large seeded peanuts usually show
a response to gypsum. In addition, gypsum
helps insure brighter hulls, which is
important for the in-shell trade. Since little
calcium taken up by the roots is moved to
the pegs and pods, uptake must be by these


structures. Gypsum recommendations are
for 400 pounds per acre for runner peanuts
and 800 pounds per acre for large-seeded
peanuts, applied in an 18-inch band over the
row. These rates are based on bagged, dry
gypsum because of consistency in purity and
moisture content. However most gypsum is
applied broadcast and is derived from the
manufacture of super-phosphate, or from
electrical power plants where gypsum is
formed as a by-product of pollution control
methods. Since this gypsum is broadcast and
contains varying amounts of moisture, a ton
per acre is usually used for large-seeded
peanuts and about half that for runner
peanuts.

EBW

Checking Tobacco Barns for Heat
Exchanger Leaks

All tobacco curing barns have been
converted from direct combustion units to
the heat exchanger system. Not allowing the
combustion gases to pass through the
tobacco has greatly reduced the level of
tobacco- specific nitrosamines (TSNA) in the
cured leaf. The nitrogen gases created by
combustion reacted with the tobacco to form
TSNA. However cracks or leaks may
develop in the heat exchanger and again
allow combustion gases to enter the curing
chamber, thereby allowing TSNA to form.
No reliable and inexpensive method of
measuring nitrogen oxides is available, so
carbon dioxide meters have become the best
method of determining if there are cracks or
leaks in the heat exchanger. County agents
have access to such a meter and can test
barns for growers. These checks should be
made before tobacco is placed in the barn for
curing.

EBW









Pesticide Potpourri

Nearly a decade after it was discovered, an
exotoxin derived from the Bacillus
thuringiensis bacterium is on the verge of
gaining commercial approval in the U.S. for
incorporation into transgenic cotton plants as
another pest insect management tool. VIP
cotton (for vegetative insecticidal protein) is
said to offer broad spectrum, full season
control of major lepidopteran pests, and
potentially Spodoptera species. However,
selected field testing in 2002 produced mixed
results with a report of excellent control of
several key insects, but inadequate impact on
others. Structurally, functionally, and
biochemically VIP is different from B.t.
delta-endotoxins. When pest insect larvae
feed on VIP cotton plants, the critical protein
is ingested, causing the larvae to stop feeding
and expire. Further field testing is
anticipated during 2003, perhaps including
head-to-head comparative trials between
current B.t.-cotton and VIP cotton.
(Syngenta Crop Protection via IPMnet,
4/25/03).

MAM

Gypsum for Peanuts

If soil tests indicate a need, or if peanuts are
being grown for seed purposes or are of the
virginia market-type, apply gypsum by the
time plants are blooming. Gypsum is a
readily available source of calcium, which is
needed as the pegs enter the soil to help
insure good pod fill and reduce some soil-
bome pod diseases. Gypsum is needed for
seed peanuts to insure good germination and
vigor, and large seeded peanuts usually show
a response to gypsum. In addition, gypsum
helps insure brighter hulls, which is
important for the in-shell trade. Since little
calcium taken up by the roots is moved to
the pegs and pods, uptake must be by these


structures. Gypsum recommendations are
for 400 pounds per acre for runner peanuts
and 800 pounds per acre for large-seeded
peanuts, applied in an 18-inch band over the
row. These rates are based on bagged, dry
gypsum because of consistency in purity and
moisture content. However most gypsum is
applied broadcast and is derived from the
manufacture of super-phosphate, or from
electrical power plants where gypsum is
formed as a by-product of pollution control
methods. Since this gypsum is broadcast and
contains varying amounts of moisture, a ton
per acre is usually used for large-seeded
peanuts and about half that for runner
peanuts.

EBW

Checking Tobacco Barns for Heat
Exchanger Leaks

All tobacco curing barns have been
converted from direct combustion units to
the heat exchanger system. Not allowing the
combustion gases to pass through the
tobacco has greatly reduced the level of
tobacco- specific nitrosamines (TSNA) in the
cured leaf. The nitrogen gases created by
combustion reacted with the tobacco to form
TSNA. However cracks or leaks may
develop in the heat exchanger and again
allow combustion gases to enter the curing
chamber, thereby allowing TSNA to form.
No reliable and inexpensive method of
measuring nitrogen oxides is available, so
carbon dioxide meters have become the best
method of determining if there are cracks or
leaks in the heat exchanger. County agents
have access to such a meter and can test
barns for growers. These checks should be
made before tobacco is placed in the barn for
curing.

EBW









Curing Tobacco

In 2002 several growers had curing
difficulties in that a disease called barn rot
developed in the curing barn. If current
rainy conditions continue, barn rot may also
be a problem in 2003. It is usually more of a
problem on the first harvests because these
leaves are thinner and more susceptible to
infection. Barn rot is caused by bacteria
which also cause a field disease known as
hollow stalk, jelly rot, soft rot, and possibly
other names. It generally enters the leaf or
stalk through a wound, and often the black
mid-rib of leaves that are infected with
necrotic potato virus-Y have the bacterial
infection. If the disease is present in the
field, it can easily cause major losses in the
curing barn because the humidity and
temperature used to yellow tobacco are ideal
for the bacterial disease to develop. The
tobacco turns black, has an offensive odor,
and is generally useless to the buyer. The
TSNA levels are also high in this tobacco,
which is called 'oxidized' by the graders.
There are no chemicals labeled for
prevention or control of bacterial soft rot,
and none are expected. Even if there is little
field disease, barn rot can still become a
problem when the leaves are wet when
placed in the barn. To avoid the problem of
barn rot, do not harvest when the leaves are
wet from dew or rain and do not harvest
leaves that are infected in the field. If there
is some moisture on the leaves, it would be
advisable to remove this moisture by opening
the vents and running the barn fan to blow
dry air through the leaves. If it is raining or
at night when the humidity is high, a very
small amount of heat for a few hours would
lower the humidity and be beneficial, but be
careful not to dry the leaf and set the green
color in the tobacco. It would also help to
harvest only ripe leaves, so that the coloring
stage of curing can be kept to a minimum.
The disease becomes less active as the


temperatures are raised for leaf drying and
the humidity is lowered.

EBW

Replacement Fertilization for Tobacco

It is likely that recent heavy rains have
leached nutrients from the soil in many
Florida tobacco fields, particularly if the
plants have not reached the topping stage.
In such cases, the upper leaves may not
mature properly and may be pale in color
after curing, often receiving a 'slick' grade.
On the other hand, applying excessive or
unneeded nitrogen fertilizer could result in
green leaves that also do not mature
properly, but will be green in color and also
receive a reduced grade. Guides for
replacement fertilization do not normally
cover tobacco that has been transplanted
more than seven weeks, but experience has
shown that, if needed and done in
moderation, applications of replacement
fertilizer can be beneficial. The source of
replacement fertilizer is important in that a
nitrate source of nitrogen be used, and that
potash be included in the application.
Nitrate of soda-potash (15-0-14) has
traditionally been the most popular and
effective source of replacement nitrogen and
potash. Rates for late application have
ranged from about 100-175 pounds of
material per acre, which supplies 15-25
pounds of N per acre. Foliar sprays would
not supply this level of nutrients.
Replacement fertilizer should be applied as
soon as possible after leaching occurs. Since
conventional equipment for applying
fertilizer to the side of the plants is not
possible because of the size of plants, other
application methods are needed. When the
planting pattern allowed, some farmers have
put dry fertilizer in every other row middle
with a distributer that was raised above the
tobacco with a specially built frame. Others









Curing Tobacco

In 2002 several growers had curing
difficulties in that a disease called barn rot
developed in the curing barn. If current
rainy conditions continue, barn rot may also
be a problem in 2003. It is usually more of a
problem on the first harvests because these
leaves are thinner and more susceptible to
infection. Barn rot is caused by bacteria
which also cause a field disease known as
hollow stalk, jelly rot, soft rot, and possibly
other names. It generally enters the leaf or
stalk through a wound, and often the black
mid-rib of leaves that are infected with
necrotic potato virus-Y have the bacterial
infection. If the disease is present in the
field, it can easily cause major losses in the
curing barn because the humidity and
temperature used to yellow tobacco are ideal
for the bacterial disease to develop. The
tobacco turns black, has an offensive odor,
and is generally useless to the buyer. The
TSNA levels are also high in this tobacco,
which is called 'oxidized' by the graders.
There are no chemicals labeled for
prevention or control of bacterial soft rot,
and none are expected. Even if there is little
field disease, barn rot can still become a
problem when the leaves are wet when
placed in the barn. To avoid the problem of
barn rot, do not harvest when the leaves are
wet from dew or rain and do not harvest
leaves that are infected in the field. If there
is some moisture on the leaves, it would be
advisable to remove this moisture by opening
the vents and running the barn fan to blow
dry air through the leaves. If it is raining or
at night when the humidity is high, a very
small amount of heat for a few hours would
lower the humidity and be beneficial, but be
careful not to dry the leaf and set the green
color in the tobacco. It would also help to
harvest only ripe leaves, so that the coloring
stage of curing can be kept to a minimum.
The disease becomes less active as the


temperatures are raised for leaf drying and
the humidity is lowered.

EBW

Replacement Fertilization for Tobacco

It is likely that recent heavy rains have
leached nutrients from the soil in many
Florida tobacco fields, particularly if the
plants have not reached the topping stage.
In such cases, the upper leaves may not
mature properly and may be pale in color
after curing, often receiving a 'slick' grade.
On the other hand, applying excessive or
unneeded nitrogen fertilizer could result in
green leaves that also do not mature
properly, but will be green in color and also
receive a reduced grade. Guides for
replacement fertilization do not normally
cover tobacco that has been transplanted
more than seven weeks, but experience has
shown that, if needed and done in
moderation, applications of replacement
fertilizer can be beneficial. The source of
replacement fertilizer is important in that a
nitrate source of nitrogen be used, and that
potash be included in the application.
Nitrate of soda-potash (15-0-14) has
traditionally been the most popular and
effective source of replacement nitrogen and
potash. Rates for late application have
ranged from about 100-175 pounds of
material per acre, which supplies 15-25
pounds of N per acre. Foliar sprays would
not supply this level of nutrients.
Replacement fertilizer should be applied as
soon as possible after leaching occurs. Since
conventional equipment for applying
fertilizer to the side of the plants is not
possible because of the size of plants, other
application methods are needed. When the
planting pattern allowed, some farmers have
put dry fertilizer in every other row middle
with a distributer that was raised above the
tobacco with a specially built frame. Others









have dissolved the fertilizer in water and
used sprayers to dribble the fertilizer solution
between every other row. Another
technique has been to use a centrifugal
broadcast fertilizer spreader that can be
raised high enough to distribute the dry
fertilizer over several rows of tobacco.
Aerial application has also been used, but
now it may be difficult to locate such a
service. Growers that have equipment to
inject fertilizer into a low pressure pivot
irrigation system may want to use this
method because of ease and uniformity of
application. Since the soils may be wet,
growers may want to limit the amount of
irrigation they use to apply the fertilizer. In
tests simulating such a procedure, only 0.05
inches of irrigation was applied and there
was no bur on the leaves. In these tests,
granular nitrate of potash (13-0-44) was
used because it has a low salt index and goes
into solution rather easily.


EBW


Pesticide Registrations and Actions

Clincher (cyhalofop-butyl) herbicide (EPA
Registration number 62719-357) for
selective postemergence grass weed control
in rice was registered on April 4, 2003.
(FDACS PREC Agenda, 5/1/03).

On April 30, EPA announced the granting of
tolerances for the herbicide safener
mefenpyr-diethyl (used with fenoxaprop) in
wheat and barley. The tolerances are 0.05
ppm for barley/wheat grain, 0.2 ppm for
barley/wheat straw, and 0.5 ppm for
barley/wheat straw. (Federal Register,
4/30/03).

On April 30, EPA announced the granting of
tolerances for the herbicide pyraflufen-ethyl
in corn (0.01 ppm), potato (0.02 ppm), and
soybean (0.01 ppm). (Federal Register,
4/30/03).


MAM


Publications


The following publications have been recently UPDATED and are available through EDIS. A
PDF file for each publication is also available.


SS-AGR-07
SS-AGR-08
SS-AGR-11
SS-AGR-12
SS-AGR-13
SS-AGR-17
SS-AGR-18
SS-AGR-25
SS-AGR-40
SS-AGR-44
SS-AGR-45
SS-AGR-46
SS-AGR-48
SS-AGR-49
SS-AGR-54


Weed Management in Small Grains Harvested for Grain 2003
Weed Management in Pastures and Rangeland 2003
Weed Management in Transgenic, Herbicide-Resistant Soybeans
Florida's Organo-Auxin Herbicide Rule 2003
Weed Management in Transgenic, Herbicide-Resistant Cotton
Brazilian Pepper Tree Control
Smutgrass Control in Perennial Grass Pastures
Tifton-9 Pensacola Bahiagrass
Cherokee Red Clover
Peanut Varieties for 2003
Natural Area Weeds: Chinese Tallow (Sapium sebiferum L.)
Liming for Production of Forage Crops in Florida
Summer Forage Legume Guide
Winter Forage Legume Guide
White Clover









have dissolved the fertilizer in water and
used sprayers to dribble the fertilizer solution
between every other row. Another
technique has been to use a centrifugal
broadcast fertilizer spreader that can be
raised high enough to distribute the dry
fertilizer over several rows of tobacco.
Aerial application has also been used, but
now it may be difficult to locate such a
service. Growers that have equipment to
inject fertilizer into a low pressure pivot
irrigation system may want to use this
method because of ease and uniformity of
application. Since the soils may be wet,
growers may want to limit the amount of
irrigation they use to apply the fertilizer. In
tests simulating such a procedure, only 0.05
inches of irrigation was applied and there
was no bur on the leaves. In these tests,
granular nitrate of potash (13-0-44) was
used because it has a low salt index and goes
into solution rather easily.


EBW


Pesticide Registrations and Actions

Clincher (cyhalofop-butyl) herbicide (EPA
Registration number 62719-357) for
selective postemergence grass weed control
in rice was registered on April 4, 2003.
(FDACS PREC Agenda, 5/1/03).

On April 30, EPA announced the granting of
tolerances for the herbicide safener
mefenpyr-diethyl (used with fenoxaprop) in
wheat and barley. The tolerances are 0.05
ppm for barley/wheat grain, 0.2 ppm for
barley/wheat straw, and 0.5 ppm for
barley/wheat straw. (Federal Register,
4/30/03).

On April 30, EPA announced the granting of
tolerances for the herbicide pyraflufen-ethyl
in corn (0.01 ppm), potato (0.02 ppm), and
soybean (0.01 ppm). (Federal Register,
4/30/03).


MAM


Publications


The following publications have been recently UPDATED and are available through EDIS. A
PDF file for each publication is also available.


SS-AGR-07
SS-AGR-08
SS-AGR-11
SS-AGR-12
SS-AGR-13
SS-AGR-17
SS-AGR-18
SS-AGR-25
SS-AGR-40
SS-AGR-44
SS-AGR-45
SS-AGR-46
SS-AGR-48
SS-AGR-49
SS-AGR-54


Weed Management in Small Grains Harvested for Grain 2003
Weed Management in Pastures and Rangeland 2003
Weed Management in Transgenic, Herbicide-Resistant Soybeans
Florida's Organo-Auxin Herbicide Rule 2003
Weed Management in Transgenic, Herbicide-Resistant Cotton
Brazilian Pepper Tree Control
Smutgrass Control in Perennial Grass Pastures
Tifton-9 Pensacola Bahiagrass
Cherokee Red Clover
Peanut Varieties for 2003
Natural Area Weeds: Chinese Tallow (Sapium sebiferum L.)
Liming for Production of Forage Crops in Florida
Summer Forage Legume Guide
Winter Forage Legume Guide
White Clover










SS-AGR-57 Tifton 85 Bermudagrass
SS-AGR-64 Grass Tetany in Cattle
SS-AGR-66 Cover Crops
SS-AGR-69 Silage Crops for Diary and Beef Cattle
SS-AGR-86 The Story Behind the IFAS Assessment of Non-Native Plants in Florida's Natural
Areas
SS-AGR-101 Application Equipment and Techniques
SS-AGR-102 Calibration of Herbicide Applicators
SS-AGR108 Using Herbicides Safely and Herbicide Toxicity
SS-AGR-109 Adjuvants
SS-AGR-110 Weed Management in Grazed Fence Rows and Non-Cropped Areas
SS-AGR-112 Poison Control Centers
SS-AGR-165 Carrotwood (Cupaniopsis anacardioides)
CIR 1204 Help Protect Florida's Natural Areas from Non-native Invasive Plants


The following NEW publications are available through EDIS. A PDF file for each publication is
also available.

SS-AGR-191 What is Agricultural Biotechnology?
SS-AGR-192 Plant Biotechnology and the Environment


The use oftrade names does not constitute a guarantee or warrant of products named and does not signify approval to the exclusion of similar
products.
Prepared by: J. M. Bennett, Chairman; C. G. Chambliss, Extension Agronomist; G. E. MacDonald, Weed Researcher, M. A. Mossler, Pest
Management Information Specialist, E. B. Whitty, Extension Agronomist. D. L. Wright, Extension Agronomist.