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 Chapter
 Crop harvest in Florida
 Corn for late planting
 Bronze wilt in cotton
 Timing cotton defoliation...
 Nitrogen status in the cotton...
 Fall forage update 2000
 Grasses
 Tobacco barn retrofitting
 Assistance to tobacco growers
 New formulation to replace Roundup...
 August crop estimates


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/UF00066352/00078
 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: July 2004
 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: UF00066352:00078

Table of Contents
    Chapter
        Page 1
    Crop harvest in Florida
        Page 2
    Corn for late planting
        Page 2
    Bronze wilt in cotton
        Page 2
    Timing cotton defoliation and harvest
        Page 2
    Nitrogen status in the cotton plant
        Page 2
    Fall forage update 2000
        Page 2
    Grasses
        Page 3
    Tobacco barn retrofitting
        Page 4
    Assistance to tobacco growers
        Page 4
    New formulation to replace Roundup Ultra
        Page 5
    August crop estimates
        Page 6
Full Text





AGRONOMY


NOTES


DATES TO REMEMBER


September 11-15
September 20-22
October 17-19


IN THIS ISSUE


Florida Association of Extension Professionals Annual Meeting Stuart
Soil and Crop Science Society of Florida Annual Meeting Tallahassee
Sunbelt Agricultural Exposition Moultrie, GA


PAGE


CORN
C orn H harvest in F lorida ................................................................................................................ 2
C o rn for L ate P lantin g .................................................................................................................. 2

COTTON
B ronze W ilt in C otton ...................................................................................... ............ ........... 2
Timing Cotton Defoliation and Harvest............................................... ............................. 2
Nitrogen Status in the Cotton Plant .............................. .. ........................................... 2

FORAGE
F all F orange U update 2000 ........................................................ ................................................ 2

TOBACCO
T tobacco B arn R retrofitting ........................................................ .............................................. 4
A assistance to Tobacco G row ers ............................................... ............................................... 4

WEEDS
New Formulation to Replace Roundup Ultra ............................ .... ............................ 5

GENERAL
A ugust C rop E stim ates ........................................................ .................................. ............ 6


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/ University of Florida / Christine Taylor Waddill, Director.


'! FLORIDA








CORN HARVEST IN FLORIDA

Much of the unirrigated corn in Florida was not harvested due
to the drought. Some fields had enough rain to keep them
going but the yield potential of the best fields without irriga-
tion was low. Irrigated corn is turning out an average yield,
but was expensive to grow because of the amount of water
needed to make the crop (as much as 20 inches). Prices are
low, but much of the crop grown is needed in the livestock
and dairy industry. Because silage is expensive to haul, it
must be grown near the dairy farms to make it a viable part of
the ration. Corn silage value in the state is now greater than
that grown for grain.

DLW

CORN FOR LATE PLANTING

We have looked at corn with tropical germplasm for many years
to allow good yields of silage and grain from late planting.
Tropical hybrids generally had good disease tolerance and
some tolerance to fall armyworm and corn earworm. How-
ever, in most years, insects reduce yield of grain and silage
by over 50% when planted in June and July. Hybrids were
released from the Mid-west that contained Bt that gave good
control of insects. However, these hybrids did not have the
disease resistance necessary to survive after the silk and tas-
sel period. The adapted tropical hybrids were generally around
135 day maturity hybrids while the mid west Bt hybrids were
about 115 day maturity. We will have a tropical Bt hybrid
available for use in the Southeast this coming year with a
maturity of about 125 days if it is successful at several test
sites across the south this year. Current evaluations look very
good for insect and disease tolerance. This may provide a
big boost to dairy producers who wish to double crop or those
who wish to grow grain after a winter crop of vegetables or
small grain.

DLW

BRONZE WILT IN COTTON

Bronze wilt has shown up again in cotton in the Southeast. The
exact cause is not known, but it shows up on certain varieties
and there are a few things that appear to trigger it. Bronze
wilt showed up in certain varieties in 1998 from late planting
(June) and amounted to less than 3% of the stand in most
cases. It usually shows up by the 10-15 node stage or earlier.
It does not appear to spread, but appears to have certain en-
vironmental factors that trigger it. After seeing the affected
plants, cotton continues to grow while these affected plants
die and are over shadowed by the developing plants. Most
plants that have bronze wilt symptoms (wilted leaves, higher
temperature if felt inthe heat of the day, and sometimes bronz-
ing or reddish discoloration of the leaves) occur at skips in
the stand --of which we have had many this year due to drought
and poor moisture conditions during germination and growth.
Much of the cotton was planted late this year or planted early


and did not germinate until late June when rains began. Bronze
wilt may occur on irrigated cotton that was late planted on
the same varieties. Even though bronze wilt occurs on cer-
tain varieties, final yield may be as good or better than on
varieties that did not show the symptoms. Seldom has it made
an impact on yield. Cotton companies are aware of the prob-
lem and are working on it. There is nothing to do to control
the problem once observed.

DLW

TIMING COTTON DEFOLIATION AND HARVEST

Timing of defoliants on cotton is critical to highyields and high
quality fiber. When NAWF (nodes above white flower) be-
come 5 or less, the crop is progressing rapidly towards cut-
out. Harvest aid timings are often based on boll maturity as
determined by slicing with a knife. Whenbolls can no longer
be sliced easily with a knife, the fiber is mature. Apply har-
vest aid chemicals when two conditions have been met: 50-
60% open bolls, and NACB (nodes above cracked bolls) =
4. Cotton and peanut compete for time, and labor on many
farms and peanut yield loss is more critical than for cotton
with delayed harvests. However, harvest aids are generally
more effective at higher temperatures when many farmers
are still harvesting peanuts. Lower rates of harvest aid chemi-
cals should be used in high temperatures to avoid sticking
leaves, which contributes to trash in the lint. Defoliation
should occur about 2 weeks prior to picking. This allows
time for bolls to open and is prior to regrowth that may stain
the lint.
JAT


NITROGEN STATUS IN THE COTTON PLANT

Late N application often complicate defoliation by delaying
maturity and causing regrowth after defoliation. N fertilizer
after the 3rd week of bloom causes late growth and is not
recommended. A heavy boll load will also slow growth and
utilize available N and make for shorter internodes reducing
the need for growth regulators. If you are monitoring petiole
nitrate-N levels and the concentration is greater than 3000
ppm, there can be problems in defoliation and regrowth.
Weather also interacts with N to further complicate the defo-
liation process. Excess moisture and high residual N at defo-
liation usually results in poor defoliation and fast regrowth.
Plan on the N status of the cotton plant to be low at defolia-
tion time and do not use high rates of N late in the season.

JAT

FALL FORAGE UPDATE 2000

Introduction
Cool season forages can supply excellent grazing for live-
stock. They are usually higher in total digestible nutrients








CORN HARVEST IN FLORIDA

Much of the unirrigated corn in Florida was not harvested due
to the drought. Some fields had enough rain to keep them
going but the yield potential of the best fields without irriga-
tion was low. Irrigated corn is turning out an average yield,
but was expensive to grow because of the amount of water
needed to make the crop (as much as 20 inches). Prices are
low, but much of the crop grown is needed in the livestock
and dairy industry. Because silage is expensive to haul, it
must be grown near the dairy farms to make it a viable part of
the ration. Corn silage value in the state is now greater than
that grown for grain.

DLW

CORN FOR LATE PLANTING

We have looked at corn with tropical germplasm for many years
to allow good yields of silage and grain from late planting.
Tropical hybrids generally had good disease tolerance and
some tolerance to fall armyworm and corn earworm. How-
ever, in most years, insects reduce yield of grain and silage
by over 50% when planted in June and July. Hybrids were
released from the Mid-west that contained Bt that gave good
control of insects. However, these hybrids did not have the
disease resistance necessary to survive after the silk and tas-
sel period. The adapted tropical hybrids were generally around
135 day maturity hybrids while the mid west Bt hybrids were
about 115 day maturity. We will have a tropical Bt hybrid
available for use in the Southeast this coming year with a
maturity of about 125 days if it is successful at several test
sites across the south this year. Current evaluations look very
good for insect and disease tolerance. This may provide a
big boost to dairy producers who wish to double crop or those
who wish to grow grain after a winter crop of vegetables or
small grain.

DLW

BRONZE WILT IN COTTON

Bronze wilt has shown up again in cotton in the Southeast. The
exact cause is not known, but it shows up on certain varieties
and there are a few things that appear to trigger it. Bronze
wilt showed up in certain varieties in 1998 from late planting
(June) and amounted to less than 3% of the stand in most
cases. It usually shows up by the 10-15 node stage or earlier.
It does not appear to spread, but appears to have certain en-
vironmental factors that trigger it. After seeing the affected
plants, cotton continues to grow while these affected plants
die and are over shadowed by the developing plants. Most
plants that have bronze wilt symptoms (wilted leaves, higher
temperature if felt inthe heat of the day, and sometimes bronz-
ing or reddish discoloration of the leaves) occur at skips in
the stand --of which we have had many this year due to drought
and poor moisture conditions during germination and growth.
Much of the cotton was planted late this year or planted early


and did not germinate until late June when rains began. Bronze
wilt may occur on irrigated cotton that was late planted on
the same varieties. Even though bronze wilt occurs on cer-
tain varieties, final yield may be as good or better than on
varieties that did not show the symptoms. Seldom has it made
an impact on yield. Cotton companies are aware of the prob-
lem and are working on it. There is nothing to do to control
the problem once observed.

DLW

TIMING COTTON DEFOLIATION AND HARVEST

Timing of defoliants on cotton is critical to highyields and high
quality fiber. When NAWF (nodes above white flower) be-
come 5 or less, the crop is progressing rapidly towards cut-
out. Harvest aid timings are often based on boll maturity as
determined by slicing with a knife. Whenbolls can no longer
be sliced easily with a knife, the fiber is mature. Apply har-
vest aid chemicals when two conditions have been met: 50-
60% open bolls, and NACB (nodes above cracked bolls) =
4. Cotton and peanut compete for time, and labor on many
farms and peanut yield loss is more critical than for cotton
with delayed harvests. However, harvest aids are generally
more effective at higher temperatures when many farmers
are still harvesting peanuts. Lower rates of harvest aid chemi-
cals should be used in high temperatures to avoid sticking
leaves, which contributes to trash in the lint. Defoliation
should occur about 2 weeks prior to picking. This allows
time for bolls to open and is prior to regrowth that may stain
the lint.
JAT


NITROGEN STATUS IN THE COTTON PLANT

Late N application often complicate defoliation by delaying
maturity and causing regrowth after defoliation. N fertilizer
after the 3rd week of bloom causes late growth and is not
recommended. A heavy boll load will also slow growth and
utilize available N and make for shorter internodes reducing
the need for growth regulators. If you are monitoring petiole
nitrate-N levels and the concentration is greater than 3000
ppm, there can be problems in defoliation and regrowth.
Weather also interacts with N to further complicate the defo-
liation process. Excess moisture and high residual N at defo-
liation usually results in poor defoliation and fast regrowth.
Plan on the N status of the cotton plant to be low at defolia-
tion time and do not use high rates of N late in the season.

JAT

FALL FORAGE UPDATE 2000

Introduction
Cool season forages can supply excellent grazing for live-
stock. They are usually higher in total digestible nutrients








CORN HARVEST IN FLORIDA

Much of the unirrigated corn in Florida was not harvested due
to the drought. Some fields had enough rain to keep them
going but the yield potential of the best fields without irriga-
tion was low. Irrigated corn is turning out an average yield,
but was expensive to grow because of the amount of water
needed to make the crop (as much as 20 inches). Prices are
low, but much of the crop grown is needed in the livestock
and dairy industry. Because silage is expensive to haul, it
must be grown near the dairy farms to make it a viable part of
the ration. Corn silage value in the state is now greater than
that grown for grain.

DLW

CORN FOR LATE PLANTING

We have looked at corn with tropical germplasm for many years
to allow good yields of silage and grain from late planting.
Tropical hybrids generally had good disease tolerance and
some tolerance to fall armyworm and corn earworm. How-
ever, in most years, insects reduce yield of grain and silage
by over 50% when planted in June and July. Hybrids were
released from the Mid-west that contained Bt that gave good
control of insects. However, these hybrids did not have the
disease resistance necessary to survive after the silk and tas-
sel period. The adapted tropical hybrids were generally around
135 day maturity hybrids while the mid west Bt hybrids were
about 115 day maturity. We will have a tropical Bt hybrid
available for use in the Southeast this coming year with a
maturity of about 125 days if it is successful at several test
sites across the south this year. Current evaluations look very
good for insect and disease tolerance. This may provide a
big boost to dairy producers who wish to double crop or those
who wish to grow grain after a winter crop of vegetables or
small grain.

DLW

BRONZE WILT IN COTTON

Bronze wilt has shown up again in cotton in the Southeast. The
exact cause is not known, but it shows up on certain varieties
and there are a few things that appear to trigger it. Bronze
wilt showed up in certain varieties in 1998 from late planting
(June) and amounted to less than 3% of the stand in most
cases. It usually shows up by the 10-15 node stage or earlier.
It does not appear to spread, but appears to have certain en-
vironmental factors that trigger it. After seeing the affected
plants, cotton continues to grow while these affected plants
die and are over shadowed by the developing plants. Most
plants that have bronze wilt symptoms (wilted leaves, higher
temperature if felt inthe heat of the day, and sometimes bronz-
ing or reddish discoloration of the leaves) occur at skips in
the stand --of which we have had many this year due to drought
and poor moisture conditions during germination and growth.
Much of the cotton was planted late this year or planted early


and did not germinate until late June when rains began. Bronze
wilt may occur on irrigated cotton that was late planted on
the same varieties. Even though bronze wilt occurs on cer-
tain varieties, final yield may be as good or better than on
varieties that did not show the symptoms. Seldom has it made
an impact on yield. Cotton companies are aware of the prob-
lem and are working on it. There is nothing to do to control
the problem once observed.

DLW

TIMING COTTON DEFOLIATION AND HARVEST

Timing of defoliants on cotton is critical to highyields and high
quality fiber. When NAWF (nodes above white flower) be-
come 5 or less, the crop is progressing rapidly towards cut-
out. Harvest aid timings are often based on boll maturity as
determined by slicing with a knife. Whenbolls can no longer
be sliced easily with a knife, the fiber is mature. Apply har-
vest aid chemicals when two conditions have been met: 50-
60% open bolls, and NACB (nodes above cracked bolls) =
4. Cotton and peanut compete for time, and labor on many
farms and peanut yield loss is more critical than for cotton
with delayed harvests. However, harvest aids are generally
more effective at higher temperatures when many farmers
are still harvesting peanuts. Lower rates of harvest aid chemi-
cals should be used in high temperatures to avoid sticking
leaves, which contributes to trash in the lint. Defoliation
should occur about 2 weeks prior to picking. This allows
time for bolls to open and is prior to regrowth that may stain
the lint.
JAT


NITROGEN STATUS IN THE COTTON PLANT

Late N application often complicate defoliation by delaying
maturity and causing regrowth after defoliation. N fertilizer
after the 3rd week of bloom causes late growth and is not
recommended. A heavy boll load will also slow growth and
utilize available N and make for shorter internodes reducing
the need for growth regulators. If you are monitoring petiole
nitrate-N levels and the concentration is greater than 3000
ppm, there can be problems in defoliation and regrowth.
Weather also interacts with N to further complicate the defo-
liation process. Excess moisture and high residual N at defo-
liation usually results in poor defoliation and fast regrowth.
Plan on the N status of the cotton plant to be low at defolia-
tion time and do not use high rates of N late in the season.

JAT

FALL FORAGE UPDATE 2000

Introduction
Cool season forages can supply excellent grazing for live-
stock. They are usually higher in total digestible nutrients








CORN HARVEST IN FLORIDA

Much of the unirrigated corn in Florida was not harvested due
to the drought. Some fields had enough rain to keep them
going but the yield potential of the best fields without irriga-
tion was low. Irrigated corn is turning out an average yield,
but was expensive to grow because of the amount of water
needed to make the crop (as much as 20 inches). Prices are
low, but much of the crop grown is needed in the livestock
and dairy industry. Because silage is expensive to haul, it
must be grown near the dairy farms to make it a viable part of
the ration. Corn silage value in the state is now greater than
that grown for grain.

DLW

CORN FOR LATE PLANTING

We have looked at corn with tropical germplasm for many years
to allow good yields of silage and grain from late planting.
Tropical hybrids generally had good disease tolerance and
some tolerance to fall armyworm and corn earworm. How-
ever, in most years, insects reduce yield of grain and silage
by over 50% when planted in June and July. Hybrids were
released from the Mid-west that contained Bt that gave good
control of insects. However, these hybrids did not have the
disease resistance necessary to survive after the silk and tas-
sel period. The adapted tropical hybrids were generally around
135 day maturity hybrids while the mid west Bt hybrids were
about 115 day maturity. We will have a tropical Bt hybrid
available for use in the Southeast this coming year with a
maturity of about 125 days if it is successful at several test
sites across the south this year. Current evaluations look very
good for insect and disease tolerance. This may provide a
big boost to dairy producers who wish to double crop or those
who wish to grow grain after a winter crop of vegetables or
small grain.

DLW

BRONZE WILT IN COTTON

Bronze wilt has shown up again in cotton in the Southeast. The
exact cause is not known, but it shows up on certain varieties
and there are a few things that appear to trigger it. Bronze
wilt showed up in certain varieties in 1998 from late planting
(June) and amounted to less than 3% of the stand in most
cases. It usually shows up by the 10-15 node stage or earlier.
It does not appear to spread, but appears to have certain en-
vironmental factors that trigger it. After seeing the affected
plants, cotton continues to grow while these affected plants
die and are over shadowed by the developing plants. Most
plants that have bronze wilt symptoms (wilted leaves, higher
temperature if felt inthe heat of the day, and sometimes bronz-
ing or reddish discoloration of the leaves) occur at skips in
the stand --of which we have had many this year due to drought
and poor moisture conditions during germination and growth.
Much of the cotton was planted late this year or planted early


and did not germinate until late June when rains began. Bronze
wilt may occur on irrigated cotton that was late planted on
the same varieties. Even though bronze wilt occurs on cer-
tain varieties, final yield may be as good or better than on
varieties that did not show the symptoms. Seldom has it made
an impact on yield. Cotton companies are aware of the prob-
lem and are working on it. There is nothing to do to control
the problem once observed.

DLW

TIMING COTTON DEFOLIATION AND HARVEST

Timing of defoliants on cotton is critical to highyields and high
quality fiber. When NAWF (nodes above white flower) be-
come 5 or less, the crop is progressing rapidly towards cut-
out. Harvest aid timings are often based on boll maturity as
determined by slicing with a knife. Whenbolls can no longer
be sliced easily with a knife, the fiber is mature. Apply har-
vest aid chemicals when two conditions have been met: 50-
60% open bolls, and NACB (nodes above cracked bolls) =
4. Cotton and peanut compete for time, and labor on many
farms and peanut yield loss is more critical than for cotton
with delayed harvests. However, harvest aids are generally
more effective at higher temperatures when many farmers
are still harvesting peanuts. Lower rates of harvest aid chemi-
cals should be used in high temperatures to avoid sticking
leaves, which contributes to trash in the lint. Defoliation
should occur about 2 weeks prior to picking. This allows
time for bolls to open and is prior to regrowth that may stain
the lint.
JAT


NITROGEN STATUS IN THE COTTON PLANT

Late N application often complicate defoliation by delaying
maturity and causing regrowth after defoliation. N fertilizer
after the 3rd week of bloom causes late growth and is not
recommended. A heavy boll load will also slow growth and
utilize available N and make for shorter internodes reducing
the need for growth regulators. If you are monitoring petiole
nitrate-N levels and the concentration is greater than 3000
ppm, there can be problems in defoliation and regrowth.
Weather also interacts with N to further complicate the defo-
liation process. Excess moisture and high residual N at defo-
liation usually results in poor defoliation and fast regrowth.
Plan on the N status of the cotton plant to be low at defolia-
tion time and do not use high rates of N late in the season.

JAT

FALL FORAGE UPDATE 2000

Introduction
Cool season forages can supply excellent grazing for live-
stock. They are usually higher in total digestible nutrients








CORN HARVEST IN FLORIDA

Much of the unirrigated corn in Florida was not harvested due
to the drought. Some fields had enough rain to keep them
going but the yield potential of the best fields without irriga-
tion was low. Irrigated corn is turning out an average yield,
but was expensive to grow because of the amount of water
needed to make the crop (as much as 20 inches). Prices are
low, but much of the crop grown is needed in the livestock
and dairy industry. Because silage is expensive to haul, it
must be grown near the dairy farms to make it a viable part of
the ration. Corn silage value in the state is now greater than
that grown for grain.

DLW

CORN FOR LATE PLANTING

We have looked at corn with tropical germplasm for many years
to allow good yields of silage and grain from late planting.
Tropical hybrids generally had good disease tolerance and
some tolerance to fall armyworm and corn earworm. How-
ever, in most years, insects reduce yield of grain and silage
by over 50% when planted in June and July. Hybrids were
released from the Mid-west that contained Bt that gave good
control of insects. However, these hybrids did not have the
disease resistance necessary to survive after the silk and tas-
sel period. The adapted tropical hybrids were generally around
135 day maturity hybrids while the mid west Bt hybrids were
about 115 day maturity. We will have a tropical Bt hybrid
available for use in the Southeast this coming year with a
maturity of about 125 days if it is successful at several test
sites across the south this year. Current evaluations look very
good for insect and disease tolerance. This may provide a
big boost to dairy producers who wish to double crop or those
who wish to grow grain after a winter crop of vegetables or
small grain.

DLW

BRONZE WILT IN COTTON

Bronze wilt has shown up again in cotton in the Southeast. The
exact cause is not known, but it shows up on certain varieties
and there are a few things that appear to trigger it. Bronze
wilt showed up in certain varieties in 1998 from late planting
(June) and amounted to less than 3% of the stand in most
cases. It usually shows up by the 10-15 node stage or earlier.
It does not appear to spread, but appears to have certain en-
vironmental factors that trigger it. After seeing the affected
plants, cotton continues to grow while these affected plants
die and are over shadowed by the developing plants. Most
plants that have bronze wilt symptoms (wilted leaves, higher
temperature if felt inthe heat of the day, and sometimes bronz-
ing or reddish discoloration of the leaves) occur at skips in
the stand --of which we have had many this year due to drought
and poor moisture conditions during germination and growth.
Much of the cotton was planted late this year or planted early


and did not germinate until late June when rains began. Bronze
wilt may occur on irrigated cotton that was late planted on
the same varieties. Even though bronze wilt occurs on cer-
tain varieties, final yield may be as good or better than on
varieties that did not show the symptoms. Seldom has it made
an impact on yield. Cotton companies are aware of the prob-
lem and are working on it. There is nothing to do to control
the problem once observed.

DLW

TIMING COTTON DEFOLIATION AND HARVEST

Timing of defoliants on cotton is critical to highyields and high
quality fiber. When NAWF (nodes above white flower) be-
come 5 or less, the crop is progressing rapidly towards cut-
out. Harvest aid timings are often based on boll maturity as
determined by slicing with a knife. Whenbolls can no longer
be sliced easily with a knife, the fiber is mature. Apply har-
vest aid chemicals when two conditions have been met: 50-
60% open bolls, and NACB (nodes above cracked bolls) =
4. Cotton and peanut compete for time, and labor on many
farms and peanut yield loss is more critical than for cotton
with delayed harvests. However, harvest aids are generally
more effective at higher temperatures when many farmers
are still harvesting peanuts. Lower rates of harvest aid chemi-
cals should be used in high temperatures to avoid sticking
leaves, which contributes to trash in the lint. Defoliation
should occur about 2 weeks prior to picking. This allows
time for bolls to open and is prior to regrowth that may stain
the lint.
JAT


NITROGEN STATUS IN THE COTTON PLANT

Late N application often complicate defoliation by delaying
maturity and causing regrowth after defoliation. N fertilizer
after the 3rd week of bloom causes late growth and is not
recommended. A heavy boll load will also slow growth and
utilize available N and make for shorter internodes reducing
the need for growth regulators. If you are monitoring petiole
nitrate-N levels and the concentration is greater than 3000
ppm, there can be problems in defoliation and regrowth.
Weather also interacts with N to further complicate the defo-
liation process. Excess moisture and high residual N at defo-
liation usually results in poor defoliation and fast regrowth.
Plan on the N status of the cotton plant to be low at defolia-
tion time and do not use high rates of N late in the season.

JAT

FALL FORAGE UPDATE 2000

Introduction
Cool season forages can supply excellent grazing for live-
stock. They are usually higher in total digestible nutrients








CORN HARVEST IN FLORIDA

Much of the unirrigated corn in Florida was not harvested due
to the drought. Some fields had enough rain to keep them
going but the yield potential of the best fields without irriga-
tion was low. Irrigated corn is turning out an average yield,
but was expensive to grow because of the amount of water
needed to make the crop (as much as 20 inches). Prices are
low, but much of the crop grown is needed in the livestock
and dairy industry. Because silage is expensive to haul, it
must be grown near the dairy farms to make it a viable part of
the ration. Corn silage value in the state is now greater than
that grown for grain.

DLW

CORN FOR LATE PLANTING

We have looked at corn with tropical germplasm for many years
to allow good yields of silage and grain from late planting.
Tropical hybrids generally had good disease tolerance and
some tolerance to fall armyworm and corn earworm. How-
ever, in most years, insects reduce yield of grain and silage
by over 50% when planted in June and July. Hybrids were
released from the Mid-west that contained Bt that gave good
control of insects. However, these hybrids did not have the
disease resistance necessary to survive after the silk and tas-
sel period. The adapted tropical hybrids were generally around
135 day maturity hybrids while the mid west Bt hybrids were
about 115 day maturity. We will have a tropical Bt hybrid
available for use in the Southeast this coming year with a
maturity of about 125 days if it is successful at several test
sites across the south this year. Current evaluations look very
good for insect and disease tolerance. This may provide a
big boost to dairy producers who wish to double crop or those
who wish to grow grain after a winter crop of vegetables or
small grain.

DLW

BRONZE WILT IN COTTON

Bronze wilt has shown up again in cotton in the Southeast. The
exact cause is not known, but it shows up on certain varieties
and there are a few things that appear to trigger it. Bronze
wilt showed up in certain varieties in 1998 from late planting
(June) and amounted to less than 3% of the stand in most
cases. It usually shows up by the 10-15 node stage or earlier.
It does not appear to spread, but appears to have certain en-
vironmental factors that trigger it. After seeing the affected
plants, cotton continues to grow while these affected plants
die and are over shadowed by the developing plants. Most
plants that have bronze wilt symptoms (wilted leaves, higher
temperature if felt inthe heat of the day, and sometimes bronz-
ing or reddish discoloration of the leaves) occur at skips in
the stand --of which we have had many this year due to drought
and poor moisture conditions during germination and growth.
Much of the cotton was planted late this year or planted early


and did not germinate until late June when rains began. Bronze
wilt may occur on irrigated cotton that was late planted on
the same varieties. Even though bronze wilt occurs on cer-
tain varieties, final yield may be as good or better than on
varieties that did not show the symptoms. Seldom has it made
an impact on yield. Cotton companies are aware of the prob-
lem and are working on it. There is nothing to do to control
the problem once observed.

DLW

TIMING COTTON DEFOLIATION AND HARVEST

Timing of defoliants on cotton is critical to highyields and high
quality fiber. When NAWF (nodes above white flower) be-
come 5 or less, the crop is progressing rapidly towards cut-
out. Harvest aid timings are often based on boll maturity as
determined by slicing with a knife. Whenbolls can no longer
be sliced easily with a knife, the fiber is mature. Apply har-
vest aid chemicals when two conditions have been met: 50-
60% open bolls, and NACB (nodes above cracked bolls) =
4. Cotton and peanut compete for time, and labor on many
farms and peanut yield loss is more critical than for cotton
with delayed harvests. However, harvest aids are generally
more effective at higher temperatures when many farmers
are still harvesting peanuts. Lower rates of harvest aid chemi-
cals should be used in high temperatures to avoid sticking
leaves, which contributes to trash in the lint. Defoliation
should occur about 2 weeks prior to picking. This allows
time for bolls to open and is prior to regrowth that may stain
the lint.
JAT


NITROGEN STATUS IN THE COTTON PLANT

Late N application often complicate defoliation by delaying
maturity and causing regrowth after defoliation. N fertilizer
after the 3rd week of bloom causes late growth and is not
recommended. A heavy boll load will also slow growth and
utilize available N and make for shorter internodes reducing
the need for growth regulators. If you are monitoring petiole
nitrate-N levels and the concentration is greater than 3000
ppm, there can be problems in defoliation and regrowth.
Weather also interacts with N to further complicate the defo-
liation process. Excess moisture and high residual N at defo-
liation usually results in poor defoliation and fast regrowth.
Plan on the N status of the cotton plant to be low at defolia-
tion time and do not use high rates of N late in the season.

JAT

FALL FORAGE UPDATE 2000

Introduction
Cool season forages can supply excellent grazing for live-
stock. They are usually higher in total digestible nutrients








and protein than our summer perennial grasses. Planting
and growing these forage crops can involve considerable ex-
pense. For these reasons they are often used only to supple-
ment frosted perennial grass pastures or low-quality hay.
Some producers may reserve them for young animals that
need higher quality forages. Winter forages cannot be grown
everywhere in the state, nor on every soil type. Some areas
and some soils are too dry during the cool season to success-
fully grow plants. Therefore, the type of winter forage and
the site where it is grown should be carefully selected. Be-
low are the recommended cool season forages and varieties
that can be grown in Florida with some success.

Recommended Cultivars (Varieties):

Grasses
RYE -- Rye is the small grain most widely used for winter
grazing. Rye is more cold tolerant than oats and generally
produces more forage than either oats or wheat. Do not plant
too early; wait until cool weather begins. Normally rye from
northern states will produce little forage in late fall or early
winter and will usually be severely damaged by leaf rust. Rec-
ommended varieties are Florida 401 and Florida Black for late
fall and early winter grazing. Wrens 96, Florida 402, Wrens
Abruzzi, Bates, Elbon, Bonel, Oklon, Maton, Pennington
Wintergraze 70, Gurley Grazer 2000, and Grazemaster for
winter and spring grazing. (Wrens 96, a new cultivar release,
is a good seed producer in Florida. Maton, Elbon, Bonel, or
Oklon are very poor seed producers.)

OATS -- May be planted and grazed earlier than rye. Very
palatable, but susceptible to freeze injury. Recommended
varieties are Florida 502, Florida 501, and Coker 820 for
early season grazing. Horizon 314 Chapman, Harrison, Terral
Secretariat LA495, Coker 227, Ozark, AR-County Seeds 833,
811, and LA604 for winter and spring grazing. Horizon 314
is a new variety that is available for the first time in 2000. It
has improved crown rust resistance, winter hardiness, and
grain and forage production.

WHEAT -- Similar to oats in yield and palatability. Less
susceptible to freeze injury than oats. Wheat should not be
planted for grazing before October 15. Plant only Hessian
fly resistant varieties for grazing. Recommended varieties
for grazing are Florida 304, Pioneer 2684, Coker 9835, Rob-
erts, GA--Gore, GA--Dozier.

RYEGRAS S -- Ryegrass is a valuable winter and spring graz-
ing crop for use on flatwoods soils or the heavier sandy loam
soils in northwest Florida. Ryegrass may be seeded alone or
with a small grain on a prepared seedbed or overseeded onto
permanent grass pastures. Seeding ryegrass with a small
grain crop lengthens the grazing season. Recommended
varieties are Jumbo, Florlina, Surrey, Jackson, Florida 80,
Magnolia, Rio, Gulf, Southern Star, Tetrablend 444, Big
Daddy, TAM 90, and Rustmaster. (Other new varieties may
be suitable but have not been tested in Florida.)


TALL FESCUE -- Fescue may be useful in a cow/calf opera-
tion at certain locations in North Florida. Gains are not ad-
equate for rapidly growing stockers. It should be planted on
clay soils or on flatwood soils that remain moist throughout
the year. Plant from November 1-December 15 period on
bermudagrass or bahiagrass. Georgia 5 is the only variety
recommended in Florida.

Legumes
WHITE CLOVER -- is usually a winter annual but may act
as a perennial under optimum fertility and moisture condi-
tions. It is adapted to moist soils throughout Florida. Pro-
duction and persistence can be limited by nematodes and other
pests. Recommended varieties are Osceola, Louisiana S-1,
Nolins Improved White, Improved Louisiana white, Regal
Ladino and Arcadia.

RED CLOVER -- is a winter annual under Florida condi-
tions and usually does not reseed itself. It will not tolerate
flooding. Recommended varieties are Cherokee, Pennscott,
Kenland, Florie, Redland, Kenstar, and Nolins. (Cherokee,
developed in Florida, is highest yielding cultivar.)

ALFALFA -- is usually grown as a winter annual in Florida.
Best use is for haylage, green chopping or hay. Requires
good management and high fertility. It will not tolerate flood-
ing or a high water table. Acreage is low in Florida because
of cost and management requirements. There are no recom-
mended varieties at this time.

CRIMSON CLOVER -- is a reseeding annual adapted to fer-
tile well-drained soils. It has a relatively short grazing sea-
son. It may be grown in combination with ryegrass or a small
grain crop. Recommended varieties are Flame, Dixie, Chief,
and Tibbee.

ARROWLEAF CLOVER -- is an annual that is similar to
crimson clover in soil adaptation, management and fertility
requirements. It is mainly grown on heavier soils in North-
west Florida. It makes more growth in late spring than crim-
son. Recommended varieties are Yuchi and Amclo.

LUPINE -- is an annual adapted to well drained soils in North
and West Florida. It is an excellent cover crop. In recent
years seed supply has been low, and production has been lim-
ited by diseases and insects. Only sweet varieties are suit-
able forforage. Recommended varieties are Tifblue and Frost.

SWEETCLOVER grows on slightly drier soils than white
clover. It will not tolerate flooding. It has an earlier but
shorter grazing season than white clover. It should be re-
seeded each year. Recommended varieties are Hubam and
Floranna.

AUSTRIAN WINTER PEAS -- (Common). This annual le-
gume is best suited to well drained soils with a high clay
content.








VETCH -- grows best on well-drained, fertile, loamy soils.
It has not generally been highly productive in Florida. Rec-
ommended varieties are Vantage, Nova II, Cahaba White,
Hairy and Common.

Remember the following:

Planting cool season forages on a clean-tilled seedbed will
result in earlier and more total production as compared to
overseeding on a grass sod. If overseeding bahiagrass, the
sod should be disked or chopped for 30 to 50 percent distur-
bance. For overseeding bermudagrass, a pasture drill or no-till
drill can be used alone. Excess forage should always be re-
moved as hay or by grazing before planting. Recent experi-
ence suggests that planting of cool season annual grasses on
bahia should be delayed until mid-November or later.

Success of winter pastures depends on rainfall. This is espe-
cially true when overseeding.

In central and south peninsular Florida sod seeding
overseedingg) of cool season annuals into an established grass
sod often fails due to insufficient soil moisture and this is
generally not recommended unless irrigation is available.

Look for opportunities to plant on a clean-till seedbed such
as: following vegetables or a row crop, after lifting sod, or in
a pasture renovation program where the sod is plowed or
turned under.

In South Central Florida, small grains and ryegrass have been
successfully grown on flatwoods in a pasture renovation pro-
gram. If the sod is turned with a moldboard plow (late
October-early November), the soil harrowed, planted, and
packed the same day, there will usually be enough moisture
conserved to establish the new planting. If equipment and
labor does not allow for such a rapid progression of work,
then it may be best to turn the sod and disk in early to
mid-October and wait (hope) for a good rain before planting.

Winter legumes are more dependable on the heavier clay soils
of Northwest Florida or on sandy soils that are underlain by a
clay layer as compared to deep upland sands or sandy
flatwoods. But white clover and ryegrass overseeded can
also be grown successfully on certain flatwoods areas in
Northeast Florida and South Central Florida where the soil
remains moist throughout the growing season.

Conserved Forage:

In early August, estimate the quantity of hay that will be
needed for the coming cool season. If additional hay is
needed, fertilize perennial grasses in order to harvest extra
hay in the fall or make arrangements to purchase extra hay.

Since both the supply and quality of hay may be low in some
areas, this might be a good time to try hay ammoniation. The


quality of old rank bahiagrass and bermudagrass often har-
vested in mid to late summer could be improved by treat-
ment with anhydrous ammonia. Because of the possibility of
toxicity symptoms (and death) in young calves, it is recom-
mended that ammoniated hay not be fed to lactating cows or
to cows just prior to calving. "Ammoniated hay should be
reserved for feeding to developing heifers, herd bulls or cull
cows that are held over the winter to obtain a greater price in
the spring market" (W. F. Brown and W. E. Kunkle, IFAS
Bulletin 888, "Improving the Feeding Value of Hay by An-
hydrous Ammonia Treatment, 1997."

Hay should be analyzed for protein and total digestible nutri-
ents (TDN). Some hays may supply the nutritional needs of
certain classes of animals without any additional protein or
energy supplements. Contact your county agricultural ex-
tension agent for information about the IFAS Extension For-
age Testing Service.

Stockpiled or standing hay crop Floralta and Bigalta
Limpograss may be fertilized from mid-August through Oc-
tober in order to accumulate growth that can be grazed dur-
ing the late fall early winter period. This accumulated growth
can supply the energy needs of a mature cow, but the protein
content of the grass will be low and a protein supplement
must be fed in order to obtain expected animal performance.
See Table 1.
CGC

TOBACCO BARN RETROFITTING

It is expected that all tobacco barns used in 2001 will be
required to have non-direct fire curing units in order for price
supports to be available to the farmer. By keeping the com-
bustion gases away from direct contact with the tobacco
leaves, compounds known as tobacco-specific nitrosamines
will not form. Several Florida growers have already installed
the required units, but many more were installed in the other
tobacco-producing states. The experiences of these growers
should be useful to those who have not made the change.
There are a number of commercial choices for the heat ex-
changer and burners, or the grower may want to construct his
own unit. There are choices between LP gas or fuel oil burn-
ers for individual barns, or steam or hot water from boilers
that serve multiple barns. Information will be made avail-
able over the next few months about the available equipment.
Since there will be a heavy demand for the equipment, Florida
growers should place their orders well before the expected
June 1 deadline to retrofit the barns.

EBW

ASSISTANCE TO TOBACCO GROWERS

There may some confusion among tobacco growers as to vari-
ous forms of financial and other assistance that has been or
will be made available to them. There was a first-year direct








VETCH -- grows best on well-drained, fertile, loamy soils.
It has not generally been highly productive in Florida. Rec-
ommended varieties are Vantage, Nova II, Cahaba White,
Hairy and Common.

Remember the following:

Planting cool season forages on a clean-tilled seedbed will
result in earlier and more total production as compared to
overseeding on a grass sod. If overseeding bahiagrass, the
sod should be disked or chopped for 30 to 50 percent distur-
bance. For overseeding bermudagrass, a pasture drill or no-till
drill can be used alone. Excess forage should always be re-
moved as hay or by grazing before planting. Recent experi-
ence suggests that planting of cool season annual grasses on
bahia should be delayed until mid-November or later.

Success of winter pastures depends on rainfall. This is espe-
cially true when overseeding.

In central and south peninsular Florida sod seeding
overseedingg) of cool season annuals into an established grass
sod often fails due to insufficient soil moisture and this is
generally not recommended unless irrigation is available.

Look for opportunities to plant on a clean-till seedbed such
as: following vegetables or a row crop, after lifting sod, or in
a pasture renovation program where the sod is plowed or
turned under.

In South Central Florida, small grains and ryegrass have been
successfully grown on flatwoods in a pasture renovation pro-
gram. If the sod is turned with a moldboard plow (late
October-early November), the soil harrowed, planted, and
packed the same day, there will usually be enough moisture
conserved to establish the new planting. If equipment and
labor does not allow for such a rapid progression of work,
then it may be best to turn the sod and disk in early to
mid-October and wait (hope) for a good rain before planting.

Winter legumes are more dependable on the heavier clay soils
of Northwest Florida or on sandy soils that are underlain by a
clay layer as compared to deep upland sands or sandy
flatwoods. But white clover and ryegrass overseeded can
also be grown successfully on certain flatwoods areas in
Northeast Florida and South Central Florida where the soil
remains moist throughout the growing season.

Conserved Forage:

In early August, estimate the quantity of hay that will be
needed for the coming cool season. If additional hay is
needed, fertilize perennial grasses in order to harvest extra
hay in the fall or make arrangements to purchase extra hay.

Since both the supply and quality of hay may be low in some
areas, this might be a good time to try hay ammoniation. The


quality of old rank bahiagrass and bermudagrass often har-
vested in mid to late summer could be improved by treat-
ment with anhydrous ammonia. Because of the possibility of
toxicity symptoms (and death) in young calves, it is recom-
mended that ammoniated hay not be fed to lactating cows or
to cows just prior to calving. "Ammoniated hay should be
reserved for feeding to developing heifers, herd bulls or cull
cows that are held over the winter to obtain a greater price in
the spring market" (W. F. Brown and W. E. Kunkle, IFAS
Bulletin 888, "Improving the Feeding Value of Hay by An-
hydrous Ammonia Treatment, 1997."

Hay should be analyzed for protein and total digestible nutri-
ents (TDN). Some hays may supply the nutritional needs of
certain classes of animals without any additional protein or
energy supplements. Contact your county agricultural ex-
tension agent for information about the IFAS Extension For-
age Testing Service.

Stockpiled or standing hay crop Floralta and Bigalta
Limpograss may be fertilized from mid-August through Oc-
tober in order to accumulate growth that can be grazed dur-
ing the late fall early winter period. This accumulated growth
can supply the energy needs of a mature cow, but the protein
content of the grass will be low and a protein supplement
must be fed in order to obtain expected animal performance.
See Table 1.
CGC

TOBACCO BARN RETROFITTING

It is expected that all tobacco barns used in 2001 will be
required to have non-direct fire curing units in order for price
supports to be available to the farmer. By keeping the com-
bustion gases away from direct contact with the tobacco
leaves, compounds known as tobacco-specific nitrosamines
will not form. Several Florida growers have already installed
the required units, but many more were installed in the other
tobacco-producing states. The experiences of these growers
should be useful to those who have not made the change.
There are a number of commercial choices for the heat ex-
changer and burners, or the grower may want to construct his
own unit. There are choices between LP gas or fuel oil burn-
ers for individual barns, or steam or hot water from boilers
that serve multiple barns. Information will be made avail-
able over the next few months about the available equipment.
Since there will be a heavy demand for the equipment, Florida
growers should place their orders well before the expected
June 1 deadline to retrofit the barns.

EBW

ASSISTANCE TO TOBACCO GROWERS

There may some confusion among tobacco growers as to vari-
ous forms of financial and other assistance that has been or
will be made available to them. There was a first-year direct








Table 1.
Seeding Rates Seeding Depth
Seed-Propagated Planting Dates (lb/A Broadcast) (inch)
Crops'

Alfalfa Oct. 1 Nov. 15 12-20 1/4 /2

Clover, Arrowleaf Oct. 1 Nov. 15 8 10 0 2

Clover, Berseem Oct. 1 Nov. 15 16 20 1/4 2

Clover, Crimson Oct. 1 Nov. 15 20 26 1/4 2

Clover, Red Oct. Nov. 15 6-12 1/4 2

Clover, Subterranean Oct. 1 Nov. 15 18 22 1/4 2

Clover, White Oct. 1 Nov. 15 3 4 0- 1/4

Fescue, Tall Nov. 1 Dec. 15 16-20 1/4 2

Oats for forage Sept. 15 Nov. 15 96 128 (3-4 bu) 1 2

Pea, Austrian Winter Oct. 1 Nov. 15 45 60 2 1

Rye for forage Oct. 15 Nov. 15 84 112 (1/5 2 bu) 1 -2

Ryegrass, Italian Oct. 1 Nov. 15 20 30 0 2
(annual)

Sweetclover Oct. 1 -Nov. 15 12 15 1/4 2

Turnips Oct. 1 -Nov. 15 5 -6 1/4 2

Vetch, hairy Oct. 1 Nov. 15 20 30 1 2

Wheat for forage Oct. 15 Nov. 15 90 120 (1.5 2 bu) 1 -2

1 Always check seed quality. Seed germination should be 80% or higher for best results.
2 Planting date range: in general, cool season forage crops in north Florida can be planted in
the early part of the planting date range and in south Florida, the latter part of the planting date
range.


payment that should already have been received from the
Phase II funds. This is being provided annually over a 12-
year period from the tobacco companies to partially com-
pensate growers for loss of quota that resulted from the to-
bacco settlements. These are not legislated funds, and dis-
bursements were made by Chase Manhattan Bank. In the
case of legislated funds, Congress passed a disaster bill last
fall that included tobacco growers, and these payments should
already have been received. A second disaster bill was passed
by the Congress this past spring, and payments should be
dispersed soon. The Florida Legislature passed a bill, using
tobacco settlement funds, that provides the Florida Depart-
ment of Agriculture and Consumer Services $2.5 million to
buy equipment which tobacco farmers no longer need in the
production of the crop. There was an additional $2.5 million
appropriated to IFAS to provide direct on-farm assistance to
tobacco growers. The details for use of the Florida legisla-
tive appropriations will be announced later.


NEW FORMULATION TO REPLACE ROUNDUP
ULTRA

Monsanto has discontinued making Roundup Ultra and has
replaced this product with the new "Roundup UltraMAX."
Roundup UltraMAX is a 5 lb/gal formulation, vs. Roundup
Ultra which was a 4 lb/gal formulation. Roundup UltraMAX
will be labeled for use as Roundup Ultra has been. Because
of the formulation change, recommendations in "pints/acre"
will no longer be used. Instead, the use rates for annual weeds
will range from 13 to 40 fl. oz/acre depending on the weed
species and height. Perennial weeds will be controlled at
ranges of 0.5 4 qt/acre and will have different water volume
(gal per acre of total solution) depending on the perennial
species. A surfactant was not recommended with any
Roundup Ultra applications. However, with Roundup
UltraMAX, there are a few situations in which a surfactant
will be beneficial.


EBW








AUGUST CROP ESTIMATES

The National Agricultural Statistics Service made the following crop acreage and yield estimates as of August 1:

Florida United States

Crop Acreage for Yield per Acre Acreage for Yield per Acre
Harvest (x1000) Harvest (x1000)

Cotton 92 420 lb 13,425 648 lb

Peanuts 80 2400 lb 1,466 2587 lb

Sugarcane 448 36 ton 993 35.8 ton

Tobacco 4.9 2500 lb 647 2169 lb

Corn, hay, soybeans, and wheat are no longer estimated for Florida.
EBW


The use of tradenames 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; E.B. Whitty, Extension Agronomist; C. G. Chambliss, Extension Agronomist; Joyce A. Tredaway;
Extension Agronomist, and D. L. Wright, Extension Agronomist, North Florida Research and Education Center.