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 Manage for lower cost producti...
 Poor small grain growth
 Top-dress winter grazing in...
 Beware of coffeeweeds in pastu...
 Summary of the agricultural health...


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/UF00066352/00064
 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: December 2005
 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: UF00066352:00064

Table of Contents
    Table of Contents
        Page 1
    Manage for lower cost production
        Page 2
    Poor small grain growth
        Page 2
    Top-dress winter grazing in January
        Page 2
    Beware of coffeeweeds in pastures
        Page 2
    Summary of the agricultural health study
        Page 3
        Page 4
Full Text





AGRONOMY
UNIVERSITY OF
FLORIDA NOTES
IFAS EXTENSION


December, 2005


IN THIS ISSUE

FORAGE
Manage for Lower Cost Production .
Poor Small Grain Growth .........
Top-dress Winter Grazing in January

WEED CONTROL
Beware of Coffeeweeds in Pastures ..


MISCELLANEOUS
Summary of the Agricultural Health Study ...........................


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 of Florida / Larry Arrington, Interim
Dean.









Manage for Lower Cost Production

Prices for fuel and fertilizer are at an all time
high. It is important for growers to consider
ways to use these resources more efficiently.
The following ideas for reducing fuel and
fertilizer prices are being implemented and
have solid research and farmer experience
behind them: 1) consider switching to
conservation tillage to minimize equipment
cost. 2) Use residual herbicides at planting,
along with glyphosate, to reduce the need
for directed applications. 3) Consider using
new genetically modified cotton technology
that will allow growers to use broadcast
glyphosate all season to save time and fuel.
4) If cover crops are to be planted, low
populations of legumes (like crimson clover)
may be used to supply some of the nitrogen
to the following cotton crop. 5) Include
cattle in cotton rotations with winter annuals
for grazing. This will result in better
utilization of nutrients by recycling nitrogen
that will be available for following crops.
Cattle in cropping systems have proven to
make the farm system more profitable and
better utilizes land and labor resources by
letting animals harvest forages. Some of
these practices will take longer to implement
into farm activity than others, but all have
shown benefit in research and farm practice.

David L. Wright

Poor Small Grain Growth

Over the years, one of the biggest causes of
poor small grain growth has been due to
lack of deep tillage. If fields are spotty with
irregular growth, this is a good indication
that deep tillage was not done over the field.
The lack of deep tillage will often show
when root systems are shallow and above
average rainfall has leached nitrogen below
the limited root system. It is very difficult


to compensate when this occurs. Many
people will try applying additional nitrogen,
but this will also leach below the shallow
root system. Sulfur may then be applied,
but the results are rarely beneficial. Poor
crop growth is most commonly seen if the
compaction layer is in the top 4-6 inches,
with fewer problems if the compaction zone
is 10-12 inches deep. Regardless, these
fields should have deep tillage done on a
routine basis to overcome these obstacles.

DavidL. Wright

Top-dress Winter Grazing in January

If small grain were planted in October or
November, it is advisable to split nitrogen
applications by using another 40-50 lbs/A in
January to stimulate growth. Applications
every 6-8 weeks keeps winter annuals
growing well without exposing large
amounts of fertilizer to leaching. Herbicides
may be applied with liquid nitrogen and
sulfur to control most broadleaf weeds. If
clovers are present in the winter grazing,
broadleaf herbicides should not be used.

DavidL. Wright




Beware of Coffeeweeds in Pastures

Coffeeweeds, both sicklepod and coffee
senna, are common pasture weeds. These
weeds are toxic to livestock, but are
unpalatable and rarely grazed when suitable
forage is present. However, coffeeweeds
are more tolerant to frost than many other
plant species. After a light frost, bahiagrass
and other pasture grasses will brown-out
while coffeeweeds remain green. It is at this









Manage for Lower Cost Production

Prices for fuel and fertilizer are at an all time
high. It is important for growers to consider
ways to use these resources more efficiently.
The following ideas for reducing fuel and
fertilizer prices are being implemented and
have solid research and farmer experience
behind them: 1) consider switching to
conservation tillage to minimize equipment
cost. 2) Use residual herbicides at planting,
along with glyphosate, to reduce the need
for directed applications. 3) Consider using
new genetically modified cotton technology
that will allow growers to use broadcast
glyphosate all season to save time and fuel.
4) If cover crops are to be planted, low
populations of legumes (like crimson clover)
may be used to supply some of the nitrogen
to the following cotton crop. 5) Include
cattle in cotton rotations with winter annuals
for grazing. This will result in better
utilization of nutrients by recycling nitrogen
that will be available for following crops.
Cattle in cropping systems have proven to
make the farm system more profitable and
better utilizes land and labor resources by
letting animals harvest forages. Some of
these practices will take longer to implement
into farm activity than others, but all have
shown benefit in research and farm practice.

David L. Wright

Poor Small Grain Growth

Over the years, one of the biggest causes of
poor small grain growth has been due to
lack of deep tillage. If fields are spotty with
irregular growth, this is a good indication
that deep tillage was not done over the field.
The lack of deep tillage will often show
when root systems are shallow and above
average rainfall has leached nitrogen below
the limited root system. It is very difficult


to compensate when this occurs. Many
people will try applying additional nitrogen,
but this will also leach below the shallow
root system. Sulfur may then be applied,
but the results are rarely beneficial. Poor
crop growth is most commonly seen if the
compaction layer is in the top 4-6 inches,
with fewer problems if the compaction zone
is 10-12 inches deep. Regardless, these
fields should have deep tillage done on a
routine basis to overcome these obstacles.

DavidL. Wright

Top-dress Winter Grazing in January

If small grain were planted in October or
November, it is advisable to split nitrogen
applications by using another 40-50 lbs/A in
January to stimulate growth. Applications
every 6-8 weeks keeps winter annuals
growing well without exposing large
amounts of fertilizer to leaching. Herbicides
may be applied with liquid nitrogen and
sulfur to control most broadleaf weeds. If
clovers are present in the winter grazing,
broadleaf herbicides should not be used.

DavidL. Wright




Beware of Coffeeweeds in Pastures

Coffeeweeds, both sicklepod and coffee
senna, are common pasture weeds. These
weeds are toxic to livestock, but are
unpalatable and rarely grazed when suitable
forage is present. However, coffeeweeds
are more tolerant to frost than many other
plant species. After a light frost, bahiagrass
and other pasture grasses will brown-out
while coffeeweeds remain green. It is at this









Manage for Lower Cost Production

Prices for fuel and fertilizer are at an all time
high. It is important for growers to consider
ways to use these resources more efficiently.
The following ideas for reducing fuel and
fertilizer prices are being implemented and
have solid research and farmer experience
behind them: 1) consider switching to
conservation tillage to minimize equipment
cost. 2) Use residual herbicides at planting,
along with glyphosate, to reduce the need
for directed applications. 3) Consider using
new genetically modified cotton technology
that will allow growers to use broadcast
glyphosate all season to save time and fuel.
4) If cover crops are to be planted, low
populations of legumes (like crimson clover)
may be used to supply some of the nitrogen
to the following cotton crop. 5) Include
cattle in cotton rotations with winter annuals
for grazing. This will result in better
utilization of nutrients by recycling nitrogen
that will be available for following crops.
Cattle in cropping systems have proven to
make the farm system more profitable and
better utilizes land and labor resources by
letting animals harvest forages. Some of
these practices will take longer to implement
into farm activity than others, but all have
shown benefit in research and farm practice.

David L. Wright

Poor Small Grain Growth

Over the years, one of the biggest causes of
poor small grain growth has been due to
lack of deep tillage. If fields are spotty with
irregular growth, this is a good indication
that deep tillage was not done over the field.
The lack of deep tillage will often show
when root systems are shallow and above
average rainfall has leached nitrogen below
the limited root system. It is very difficult


to compensate when this occurs. Many
people will try applying additional nitrogen,
but this will also leach below the shallow
root system. Sulfur may then be applied,
but the results are rarely beneficial. Poor
crop growth is most commonly seen if the
compaction layer is in the top 4-6 inches,
with fewer problems if the compaction zone
is 10-12 inches deep. Regardless, these
fields should have deep tillage done on a
routine basis to overcome these obstacles.

DavidL. Wright

Top-dress Winter Grazing in January

If small grain were planted in October or
November, it is advisable to split nitrogen
applications by using another 40-50 lbs/A in
January to stimulate growth. Applications
every 6-8 weeks keeps winter annuals
growing well without exposing large
amounts of fertilizer to leaching. Herbicides
may be applied with liquid nitrogen and
sulfur to control most broadleaf weeds. If
clovers are present in the winter grazing,
broadleaf herbicides should not be used.

DavidL. Wright




Beware of Coffeeweeds in Pastures

Coffeeweeds, both sicklepod and coffee
senna, are common pasture weeds. These
weeds are toxic to livestock, but are
unpalatable and rarely grazed when suitable
forage is present. However, coffeeweeds
are more tolerant to frost than many other
plant species. After a light frost, bahiagrass
and other pasture grasses will brown-out
while coffeeweeds remain green. It is at this









Manage for Lower Cost Production

Prices for fuel and fertilizer are at an all time
high. It is important for growers to consider
ways to use these resources more efficiently.
The following ideas for reducing fuel and
fertilizer prices are being implemented and
have solid research and farmer experience
behind them: 1) consider switching to
conservation tillage to minimize equipment
cost. 2) Use residual herbicides at planting,
along with glyphosate, to reduce the need
for directed applications. 3) Consider using
new genetically modified cotton technology
that will allow growers to use broadcast
glyphosate all season to save time and fuel.
4) If cover crops are to be planted, low
populations of legumes (like crimson clover)
may be used to supply some of the nitrogen
to the following cotton crop. 5) Include
cattle in cotton rotations with winter annuals
for grazing. This will result in better
utilization of nutrients by recycling nitrogen
that will be available for following crops.
Cattle in cropping systems have proven to
make the farm system more profitable and
better utilizes land and labor resources by
letting animals harvest forages. Some of
these practices will take longer to implement
into farm activity than others, but all have
shown benefit in research and farm practice.

David L. Wright

Poor Small Grain Growth

Over the years, one of the biggest causes of
poor small grain growth has been due to
lack of deep tillage. If fields are spotty with
irregular growth, this is a good indication
that deep tillage was not done over the field.
The lack of deep tillage will often show
when root systems are shallow and above
average rainfall has leached nitrogen below
the limited root system. It is very difficult


to compensate when this occurs. Many
people will try applying additional nitrogen,
but this will also leach below the shallow
root system. Sulfur may then be applied,
but the results are rarely beneficial. Poor
crop growth is most commonly seen if the
compaction layer is in the top 4-6 inches,
with fewer problems if the compaction zone
is 10-12 inches deep. Regardless, these
fields should have deep tillage done on a
routine basis to overcome these obstacles.

DavidL. Wright

Top-dress Winter Grazing in January

If small grain were planted in October or
November, it is advisable to split nitrogen
applications by using another 40-50 lbs/A in
January to stimulate growth. Applications
every 6-8 weeks keeps winter annuals
growing well without exposing large
amounts of fertilizer to leaching. Herbicides
may be applied with liquid nitrogen and
sulfur to control most broadleaf weeds. If
clovers are present in the winter grazing,
broadleaf herbicides should not be used.

DavidL. Wright




Beware of Coffeeweeds in Pastures

Coffeeweeds, both sicklepod and coffee
senna, are common pasture weeds. These
weeds are toxic to livestock, but are
unpalatable and rarely grazed when suitable
forage is present. However, coffeeweeds
are more tolerant to frost than many other
plant species. After a light frost, bahiagrass
and other pasture grasses will brown-out
while coffeeweeds remain green. It is at this









time that animals are more likely to browse
coffeeweed in search of fresh forage.

The symptoms of coffeeweed poisoning
range from weakness and dark urine, in
slight cases, to "alert downers" in more
extreme situations. An alert downer will be
fully aware and willing to eat, but unable to
stand. The toxin in coffeeweed has not been
identified and treatment for affected animals
is unknown. Therefore, if an animal
consumes a sufficient quantity of
coffeeweed and becomes a downer, there are
no effective treatments and recovery is not
likely.

Coffeeweeds are annual plants that
germinate each spring from seed and die in
the winter. Therefore, the most effective
means of controlling coffeeweed this time of
year is by mowing. Clipping areas with
high coffeeweed density is essential while
controlling individual plants is less
important. Mowing should completely
eliminate the weed and regrowth is not
likely to occur until next spring when seed
germination begins.

Jason A. Ferrell

Summary of the Agricultural Health
Study

The Agricultural Health Study is a long-
term survey of pesticide applicators and
their families with the primary objective to
determine if pesticides used in their work
are associated with health problems. More
than 55,000 farm pesticide applicators,
30,000 farm spouses, and 5,000 commercial
applicators participated in the study, which
was conducted in North Carolina and Iowa.
The team effort was conducted by the
National Cancer Institute, National Institute
of Environmental Health Sciences, U.S.
EPA, University of Iowa, the Battelle


Centers for Public Health Research and
Evaluation, and the National Institute of
Occupational Safety and Health. The study
reflected agriculture in those two states,
primarily corn, soybean and hog production
in Iowa, while North Carolina's agriculture
is a much more diverse group of
commodities. Of the farm wives, 51 percent
actually engaged in active farm work and 40
percent of those mixed or applied pesticides.

The survey took many factors into account,
primarily related to participant lifestyles and
their medical histories. A major survey
hypothesis was that cancer rates of pesticide
applicators are greater than those of the
general population. Other questions of
interest were how spouses differ in exposure
to pesticides and if certain pesticides pose
greater risks to applicators and their
spouses. Of the 50 pesticides identified used
by the applicators and their spouses, 2,4-D
and glyphosate were the two used greatest in
both Iowa and North Carolina.

The study also introduced an interesting
approach to estimating a person's lifetime
exposure level to pesticides. This was done
by assigning a point value based on a
person's average work-day exposure, the
number of days exposed per year and the
number of years of pesticide use. The work-
day exposure factor used a point system
based upon practices involving mixing,
application, equipment repair and use of
protective equipment. For example, more
points were assigned to applicators who
repaired their own equipment versus those
who did not. Exposure levels were then
correlated with cancer and other health-
related incidents reported by those
participating in the survey.

Although this study only involved
correlation, and not cause and effect, there
were some interesting findings. The overall









cancer risk for pesticide applicators was
lower than that of the overall population and
of the 20 specific types of cancers, pesticide
applicators had lower incidence in 18 of
those. Applicators did have greater risk (14
percent) of prostate cancer and their spouses
were shown to have greater skin melanoma
risk compared to the general population. In
Iowa, applicators' children had slightly
higher rates of all cancers and lymphomas
compared to Iowa's general population.
With prostate cancer, there was more
association in those who were rated to have
"high exposure" to methyl bromide and to
chlorinated pesticides (men over 50 years of
age with a family history of prostate cancer).
Methyl bromide was a common soil
fumigant used in North Carolina, and the
greatest number of incidents with prostate
cancer was reported to be in North Carolina.
With men who had a family history of
prostate cancer, there were 5 pesticides
showing a correlation. Farmers' wives had
no clear association for any of the 50
pesticides related to breast cancer incidence.
Comparing those farmers' wives (ages 21 to
40) who mixed and applied pesticides versus
those who did not, there were some


differences in female reproductive health
aspects. The wives who mixed and applied
pesticides appeared to have longer and
missed menstrual periods compared to those
who did not mix and apply. Several other
health aspects were of interest, including
nervous system health. The use of
fungicides was associated with retinal
degeneration in both farmers and their
wives. Other health aspects were reported
and the entire study may be viewed at
http://extension.tox.ncsu.edu/index.html.

The study is ongoing and will continue until
at least 2013. Although the study is based
upon correlation and not cause and effect,
these findings stress the continuous need to
take into account why it is important to
safely use pesticides. Such basics, including
reviewing labels and properly using
protective equipment, are important.
Prostate screenings are a necessity,
especially in men over the age of 50.
Finally, using sunscreen and covering
exposed skin, should be stressed, especially
under Florida's conditions.

FredM. Fishel


The use of trade 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; M.B. Adjei, Forage Agronomist (mbadjei@ifas.ufl.edu); J.A. Ferrell, Extension Agronomist
(jaferrell@ifas.ufl.edu); F.M. Fishel, Pesticide Coordinator (weeddr@ifas.ufl.edu); C.R. Rainbolt, Extension Agronomist
(crrainbolt@ifas.ufl.edu); B.A. Sellers, Extension Agronomist (sellersb@ifas.ufl.edu); E.B. Whitty, Extension Agronomist
(ebw@ifas.ufl.edu); D.L. Wright, Extension Agronomist (dlw@ifas.ufl.edu).