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 Table of Contents
 Drought stricken corn
 Late planted corn
 Cutout in cotton and drought
 Peanut growth and management in...
 Is there a difference between milestone...
 Goatweed and pastures
 How herbicides work - GARLON/R...
 Progress of EPA's review of all...


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Agronomy notes
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Permanent Link: http://ufdc.ufl.edu/UF00066352/00071
 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: August 2006
 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: UF00066352:00071

Table of Contents
    Table of Contents
        Page 1
    Drought stricken corn
        Page 2
    Late planted corn
        Page 2
    Cutout in cotton and drought
        Page 2
    Peanut growth and management in dry weather
        Page 3
    Is there a difference between milestone and forefront?
        Page 3
    Goatweed and pastures
        Page 3
    How herbicides work - GARLON/REMEDY
        Page 4
    Progress of EPA's review of all pesticides
        Page 5
Full Text






AGRONOMY

UNIVERSITY OF
FLORIDA N T
IFAS EXTENSION

Vol. 30:8 August 2006


DATES TO REMEMBER

August 3: Extension Row Crops Field Day, Jay, Florida.




IN THIS ISSUE

CORN
Drought Stricken Corn
Late Planted Corn

COTTON
Cutout in Cotton and Drought

PEANUTS
Peanut Growth and Management in Dry Weather

WEED CONTROL
Is There a Difference Between Milestone and Forefront?
Goatweed in Pastures
How Herbicides Work GARLON/REMEDY

MISCELLANEOUS
Progress of EPA's Review of All Pesticides


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, Dean.










Drought Stricken Corn

Care should be taken in grazing drought stricken
corn and other annual summer grasses. During
these conditions it is possible for nitrate to
accumulate and result in nitrate toxicity in
animals. Highest levels of nitrates are always
found in the bottom parts of the stalk and
decrease as they go up the plant; leaves
commonly have the lowest nitrate levels.
Therefore, the upper portion of plants can often
be utilized with less possibility of toxicity to the
grazing animal than if grazed to the ground.
However, when rains begin, nitrate levels will be
reduced and the plants again become suitable
forage. It is important to note that if there is any
doubt about the suitability of the forage, a
sample should be sent for analysis or the crop
should be destroyed as to not threaten animal
health.

David Wright

Late Planted Corn

Certain types of corn can be planted in July and
early August with satisfactory yields for grain
and silage. Most of the corn hybrids that
produce satisfactory levels of grain or silage
came from tropical countries and are often called
"tropical cor". However, these hybrids are not
radically different from hybrids developed from
the Midwest, but disease resistance is often
greater in these lines. There are some tropical
corn hybrids that have very good resistance to
diseases and we have one commercial hybrid
that has the Bt gene for insect control (mainly
fall armyworm and corn earworm). Be sure to
select tropical hybrids for planting in July and
August since most of the other hybrids have
been shown to have less than 50% of the yield of
these hybrids. The Bt hybrids tend to add more
to yield in June, July, and August planting than
they do to April or May plantings.

David Wright

Cutout in Cotton and Drought

Cotton has prematurely bloomed out the top or
reached cutout in many cotton fields due to dry


weather. Cotton is only 15-30" tall in many of
these fields with white blooms showing in the
top of the plant. "Cutout" in cotton is when
there is a marked decrease in growth, flowering,
and boll retention. It is usually not a clearly
defined event, but occurs over a 1 to 2 week
period. The best way to monitor this is to count
nodes above the highest white flower. When
you have only 4-5 nodes above white flower
(NAWF), the cutout stage has been reached.
This is often noticeable when many white
blooms near the top of the plant are obvious.
NAWF declines by about one node for every
week of bloom. However, this decline is
affected by the use of growth regulator, fertility,
and moisture. If the plant is stressed before
bloom as has been the case with drought this
year, the plant may start out blooming at 7
NAWF. However, if you get into a rainy period,
this may stay at 7 for several weeks. It normally
takes 4-5 weeks of effective bloom to make a
high yielding crop. Cotton will normally have
an effective bloom period from early to mid July
until the first week of September, depending on
planting date. These late blooms often
contribute little to final yield. If NAWF is
decreasing too rapidly, growers should attempt
to determine the cause of the stress and alleviate
it if possible. If cutout is due to a high boll load,
this is good and will lead to early maturity and
harvest. If cutout is due to water stress, or
fertility, appropriate steps should be taken to
keep the plants growing and setting fruit until an
appropriate boll load is set. On some extremely
fertile, moist soils, cutout may not occur until
weeks past the effective bloom date (about 7-10
of September since it takes at least 60 days to
mature a boll late in the fall). Defoliation should
then be determined by the larger, earlier set bolls
that will contribute most to final yield with little
thought for the status of the late bolls. Fields
near cutout in the first week of August were
either planted early or have some stress factor
such as the drought that has occurred this year.
Cotton may begin to grow again this year if
normal summer rains start in August. This may
activate any nitrogen that was applied and can
result in vegetative growth at the expense of boll
set. Yield has already been impacted in many
fields due to the dry weather and it may be too
late for many of










Drought Stricken Corn

Care should be taken in grazing drought stricken
corn and other annual summer grasses. During
these conditions it is possible for nitrate to
accumulate and result in nitrate toxicity in
animals. Highest levels of nitrates are always
found in the bottom parts of the stalk and
decrease as they go up the plant; leaves
commonly have the lowest nitrate levels.
Therefore, the upper portion of plants can often
be utilized with less possibility of toxicity to the
grazing animal than if grazed to the ground.
However, when rains begin, nitrate levels will be
reduced and the plants again become suitable
forage. It is important to note that if there is any
doubt about the suitability of the forage, a
sample should be sent for analysis or the crop
should be destroyed as to not threaten animal
health.

David Wright

Late Planted Corn

Certain types of corn can be planted in July and
early August with satisfactory yields for grain
and silage. Most of the corn hybrids that
produce satisfactory levels of grain or silage
came from tropical countries and are often called
"tropical cor". However, these hybrids are not
radically different from hybrids developed from
the Midwest, but disease resistance is often
greater in these lines. There are some tropical
corn hybrids that have very good resistance to
diseases and we have one commercial hybrid
that has the Bt gene for insect control (mainly
fall armyworm and corn earworm). Be sure to
select tropical hybrids for planting in July and
August since most of the other hybrids have
been shown to have less than 50% of the yield of
these hybrids. The Bt hybrids tend to add more
to yield in June, July, and August planting than
they do to April or May plantings.

David Wright

Cutout in Cotton and Drought

Cotton has prematurely bloomed out the top or
reached cutout in many cotton fields due to dry


weather. Cotton is only 15-30" tall in many of
these fields with white blooms showing in the
top of the plant. "Cutout" in cotton is when
there is a marked decrease in growth, flowering,
and boll retention. It is usually not a clearly
defined event, but occurs over a 1 to 2 week
period. The best way to monitor this is to count
nodes above the highest white flower. When
you have only 4-5 nodes above white flower
(NAWF), the cutout stage has been reached.
This is often noticeable when many white
blooms near the top of the plant are obvious.
NAWF declines by about one node for every
week of bloom. However, this decline is
affected by the use of growth regulator, fertility,
and moisture. If the plant is stressed before
bloom as has been the case with drought this
year, the plant may start out blooming at 7
NAWF. However, if you get into a rainy period,
this may stay at 7 for several weeks. It normally
takes 4-5 weeks of effective bloom to make a
high yielding crop. Cotton will normally have
an effective bloom period from early to mid July
until the first week of September, depending on
planting date. These late blooms often
contribute little to final yield. If NAWF is
decreasing too rapidly, growers should attempt
to determine the cause of the stress and alleviate
it if possible. If cutout is due to a high boll load,
this is good and will lead to early maturity and
harvest. If cutout is due to water stress, or
fertility, appropriate steps should be taken to
keep the plants growing and setting fruit until an
appropriate boll load is set. On some extremely
fertile, moist soils, cutout may not occur until
weeks past the effective bloom date (about 7-10
of September since it takes at least 60 days to
mature a boll late in the fall). Defoliation should
then be determined by the larger, earlier set bolls
that will contribute most to final yield with little
thought for the status of the late bolls. Fields
near cutout in the first week of August were
either planted early or have some stress factor
such as the drought that has occurred this year.
Cotton may begin to grow again this year if
normal summer rains start in August. This may
activate any nitrogen that was applied and can
result in vegetative growth at the expense of boll
set. Yield has already been impacted in many
fields due to the dry weather and it may be too
late for many of










Drought Stricken Corn

Care should be taken in grazing drought stricken
corn and other annual summer grasses. During
these conditions it is possible for nitrate to
accumulate and result in nitrate toxicity in
animals. Highest levels of nitrates are always
found in the bottom parts of the stalk and
decrease as they go up the plant; leaves
commonly have the lowest nitrate levels.
Therefore, the upper portion of plants can often
be utilized with less possibility of toxicity to the
grazing animal than if grazed to the ground.
However, when rains begin, nitrate levels will be
reduced and the plants again become suitable
forage. It is important to note that if there is any
doubt about the suitability of the forage, a
sample should be sent for analysis or the crop
should be destroyed as to not threaten animal
health.

David Wright

Late Planted Corn

Certain types of corn can be planted in July and
early August with satisfactory yields for grain
and silage. Most of the corn hybrids that
produce satisfactory levels of grain or silage
came from tropical countries and are often called
"tropical cor". However, these hybrids are not
radically different from hybrids developed from
the Midwest, but disease resistance is often
greater in these lines. There are some tropical
corn hybrids that have very good resistance to
diseases and we have one commercial hybrid
that has the Bt gene for insect control (mainly
fall armyworm and corn earworm). Be sure to
select tropical hybrids for planting in July and
August since most of the other hybrids have
been shown to have less than 50% of the yield of
these hybrids. The Bt hybrids tend to add more
to yield in June, July, and August planting than
they do to April or May plantings.

David Wright

Cutout in Cotton and Drought

Cotton has prematurely bloomed out the top or
reached cutout in many cotton fields due to dry


weather. Cotton is only 15-30" tall in many of
these fields with white blooms showing in the
top of the plant. "Cutout" in cotton is when
there is a marked decrease in growth, flowering,
and boll retention. It is usually not a clearly
defined event, but occurs over a 1 to 2 week
period. The best way to monitor this is to count
nodes above the highest white flower. When
you have only 4-5 nodes above white flower
(NAWF), the cutout stage has been reached.
This is often noticeable when many white
blooms near the top of the plant are obvious.
NAWF declines by about one node for every
week of bloom. However, this decline is
affected by the use of growth regulator, fertility,
and moisture. If the plant is stressed before
bloom as has been the case with drought this
year, the plant may start out blooming at 7
NAWF. However, if you get into a rainy period,
this may stay at 7 for several weeks. It normally
takes 4-5 weeks of effective bloom to make a
high yielding crop. Cotton will normally have
an effective bloom period from early to mid July
until the first week of September, depending on
planting date. These late blooms often
contribute little to final yield. If NAWF is
decreasing too rapidly, growers should attempt
to determine the cause of the stress and alleviate
it if possible. If cutout is due to a high boll load,
this is good and will lead to early maturity and
harvest. If cutout is due to water stress, or
fertility, appropriate steps should be taken to
keep the plants growing and setting fruit until an
appropriate boll load is set. On some extremely
fertile, moist soils, cutout may not occur until
weeks past the effective bloom date (about 7-10
of September since it takes at least 60 days to
mature a boll late in the fall). Defoliation should
then be determined by the larger, earlier set bolls
that will contribute most to final yield with little
thought for the status of the late bolls. Fields
near cutout in the first week of August were
either planted early or have some stress factor
such as the drought that has occurred this year.
Cotton may begin to grow again this year if
normal summer rains start in August. This may
activate any nitrogen that was applied and can
result in vegetative growth at the expense of boll
set. Yield has already been impacted in many
fields due to the dry weather and it may be too
late for many of










these fields to make an average crop if weather
conditions improve.

David Wright

Peanut Growth and Management in Dry
Weather

Peanuts have not grown as rapidly as normal
with dry soil conditions. Although many fields
of peanuts have not lapped in the middles, there
is plenty of season left to make a peanut crop.
Management for the remainder of the season
includes weed and disease control as well as
applications of boron (B) if needed. Boron is a
highly mobile nutrient and many deficient fields
were found in 2005 with the high amount of
rainfall during the growing season. High
application rates of other nutrients can, in turn,
make B deficiency more pronounced.
Deficiencies are most often found on highly
weathered, sandy soils. The deficiency that we
most often associate with B deficiency is
internal fruit damage that we call "hollow
heart", which reduces the quality and value of
the crop. However, in more severe cases, B
deficiency can result in split stems and roots, on
the lower part of the stem with shortened
intemodes, terminal death, and extensive
secondary branching. Leaves may be dark green
and mottled with few or no peanuts developing
on stubbed pegs. Boron application is a routine
recommendation for peanuts grown in Florida
even if deficiencies are not seen. Boron may be
applied early with herbicides or with fungicides
to keep from making additional trips across the
field. Split applications are desirable on sandy
fields with a total of V2 to 34 pound of B per acre
for the year. The crop may take up less then a
tenth of a pound per acre but it is still important
for crop production.

David Wright

Is There a Difference Between Milestone and
Forefront?

Milestone is a relatively new herbicide that has
been heavily advertised in Florida for the past
year since it provides excellent control of
tropical soda apple (TSA). In just a few months,


it replaced Remedy as the most common
herbicide used for TSA control. However, UF
IFAS research has shown that Milestone is a
very specific herbicide that fails to control many
common weeds such as dogfennel and
blackberry. In light of the limited weed control
spectrum of Milestone, Forefront herbicide is
also being sold in Florida. These two products
hitting the market so close together that it has
caused some confusion about which product is
best to use.

Forefront is a combination of Milestone + 2,4-D.
The 2,4-D in this mixture comes at little or no
additional cost and it improves control of
dogfennel and several other weeds. Therefore,
you will likely see more weeds controled with
Forefront that Milestone for an equivalent price.

When spot-treating TSA, either Milestone or
Forefront will be effective options. When
broadcasting the herbicide to the entire field,
Forefront will generally control more weeds
than if using Milestone alone.

Jason Ferrell

Goatweed in Pastures

Goatweed has been a problematic in Florida for
many years, primarily in citrus (Figure 1).
However, we are now seeing more and more
goatweed invade pastures and rangeland. This
weed is particularly troublesome, and dense, in
areas that have been overgrazed or previously
harvested for sod.










these fields to make an average crop if weather
conditions improve.

David Wright

Peanut Growth and Management in Dry
Weather

Peanuts have not grown as rapidly as normal
with dry soil conditions. Although many fields
of peanuts have not lapped in the middles, there
is plenty of season left to make a peanut crop.
Management for the remainder of the season
includes weed and disease control as well as
applications of boron (B) if needed. Boron is a
highly mobile nutrient and many deficient fields
were found in 2005 with the high amount of
rainfall during the growing season. High
application rates of other nutrients can, in turn,
make B deficiency more pronounced.
Deficiencies are most often found on highly
weathered, sandy soils. The deficiency that we
most often associate with B deficiency is
internal fruit damage that we call "hollow
heart", which reduces the quality and value of
the crop. However, in more severe cases, B
deficiency can result in split stems and roots, on
the lower part of the stem with shortened
intemodes, terminal death, and extensive
secondary branching. Leaves may be dark green
and mottled with few or no peanuts developing
on stubbed pegs. Boron application is a routine
recommendation for peanuts grown in Florida
even if deficiencies are not seen. Boron may be
applied early with herbicides or with fungicides
to keep from making additional trips across the
field. Split applications are desirable on sandy
fields with a total of V2 to 34 pound of B per acre
for the year. The crop may take up less then a
tenth of a pound per acre but it is still important
for crop production.

David Wright

Is There a Difference Between Milestone and
Forefront?

Milestone is a relatively new herbicide that has
been heavily advertised in Florida for the past
year since it provides excellent control of
tropical soda apple (TSA). In just a few months,


it replaced Remedy as the most common
herbicide used for TSA control. However, UF
IFAS research has shown that Milestone is a
very specific herbicide that fails to control many
common weeds such as dogfennel and
blackberry. In light of the limited weed control
spectrum of Milestone, Forefront herbicide is
also being sold in Florida. These two products
hitting the market so close together that it has
caused some confusion about which product is
best to use.

Forefront is a combination of Milestone + 2,4-D.
The 2,4-D in this mixture comes at little or no
additional cost and it improves control of
dogfennel and several other weeds. Therefore,
you will likely see more weeds controled with
Forefront that Milestone for an equivalent price.

When spot-treating TSA, either Milestone or
Forefront will be effective options. When
broadcasting the herbicide to the entire field,
Forefront will generally control more weeds
than if using Milestone alone.

Jason Ferrell

Goatweed in Pastures

Goatweed has been a problematic in Florida for
many years, primarily in citrus (Figure 1).
However, we are now seeing more and more
goatweed invade pastures and rangeland. This
weed is particularly troublesome, and dense, in
areas that have been overgrazed or previously
harvested for sod.










these fields to make an average crop if weather
conditions improve.

David Wright

Peanut Growth and Management in Dry
Weather

Peanuts have not grown as rapidly as normal
with dry soil conditions. Although many fields
of peanuts have not lapped in the middles, there
is plenty of season left to make a peanut crop.
Management for the remainder of the season
includes weed and disease control as well as
applications of boron (B) if needed. Boron is a
highly mobile nutrient and many deficient fields
were found in 2005 with the high amount of
rainfall during the growing season. High
application rates of other nutrients can, in turn,
make B deficiency more pronounced.
Deficiencies are most often found on highly
weathered, sandy soils. The deficiency that we
most often associate with B deficiency is
internal fruit damage that we call "hollow
heart", which reduces the quality and value of
the crop. However, in more severe cases, B
deficiency can result in split stems and roots, on
the lower part of the stem with shortened
intemodes, terminal death, and extensive
secondary branching. Leaves may be dark green
and mottled with few or no peanuts developing
on stubbed pegs. Boron application is a routine
recommendation for peanuts grown in Florida
even if deficiencies are not seen. Boron may be
applied early with herbicides or with fungicides
to keep from making additional trips across the
field. Split applications are desirable on sandy
fields with a total of V2 to 34 pound of B per acre
for the year. The crop may take up less then a
tenth of a pound per acre but it is still important
for crop production.

David Wright

Is There a Difference Between Milestone and
Forefront?

Milestone is a relatively new herbicide that has
been heavily advertised in Florida for the past
year since it provides excellent control of
tropical soda apple (TSA). In just a few months,


it replaced Remedy as the most common
herbicide used for TSA control. However, UF
IFAS research has shown that Milestone is a
very specific herbicide that fails to control many
common weeds such as dogfennel and
blackberry. In light of the limited weed control
spectrum of Milestone, Forefront herbicide is
also being sold in Florida. These two products
hitting the market so close together that it has
caused some confusion about which product is
best to use.

Forefront is a combination of Milestone + 2,4-D.
The 2,4-D in this mixture comes at little or no
additional cost and it improves control of
dogfennel and several other weeds. Therefore,
you will likely see more weeds controled with
Forefront that Milestone for an equivalent price.

When spot-treating TSA, either Milestone or
Forefront will be effective options. When
broadcasting the herbicide to the entire field,
Forefront will generally control more weeds
than if using Milestone alone.

Jason Ferrell

Goatweed in Pastures

Goatweed has been a problematic in Florida for
many years, primarily in citrus (Figure 1).
However, we are now seeing more and more
goatweed invade pastures and rangeland. This
weed is particularly troublesome, and dense, in
areas that have been overgrazed or previously
harvested for sod.










Goatweed (Scoparia dulcis) is considered an
annual weed, but it can also be exist as a
perennial in south Florida. Plants can grow at
least 36 inches tall, with leaves 0.5 to 3 inches
long on short petioles. Each goatweed plant is
capable of producing thousands of seeds that are
approximately 0.25 mm in diameter that can be
spread by wind, water, and equipment. In north
Florida, this weed flowers and sets seeds many
times until frost. In south Florida, it appears that
flowering and fruiting can occur year-round.

A study was conducted at the University of
Florida in the mid- to late 1980s that
investigated goatweed seed germination. The
authors found that goatweed seeds do not
germinate under dark conditions. This means
that there must be at least some light for
germination to occur. In fact, as little at 6 hours
of light resulted in approximately 18%
germination, with maximum germination
occurring with 9 to 13 hours of light. Therefore,
a thick, healthy sward would limit the amount of
goatweed germination in a pasture.

Proper pasture management can go along way in
controlling this weed, especially if you consider
that this plant can tolerate 2 lb/acre of
glyphosate quite well. To date, the only sure-
fire herbicide for goatweed control in pastures is
Cimarron at 0.3 oz/acre. However, this is
problematic for producers who graze bahiagrass
since Cimarron has the potential for severe
bahiagrass injury. For bahiagrass, at least 3
pints/acre ofWeedMaster will be needed for
suppression (not control).

Brent A. Sellers

How Herbicides Work -
GARLON/REMEDY

Garlon and Remedy are herbicides that contain
the active ingredient triclopyr. Garlon is
registered for use in forestry and industrial sites,
while Remedy is used for weed control in
pasture and rangelands. There are other
registrations for triclopyr in aquatic areas under
the trade name Renovate. Regardless of
triclopyr formulation or label specifications, this


herbicide is active on a wide range ofbroadleaf
weeds, both annual and perennial species.

Triclopyr is classified as a growth regulating
herbicide. It is applied postemergence, over-the-
top of weeds and desirable vegetation. Most
often, the desirable vegetation is pasture or
rangeland grasses. Triclopyr is readily absorbed
through the foliage and diffuses into leaf cells.
This herbicide is systemic, meaning it is mobile
within plants.

Once inside the cell, triclopyr will do one of the
following:

1) Cause herbicide activity, resulting in injury or
death of the plant
2) Be metabolized into non-toxic compounds
3) Be moved out of the cell and translocated into
other areas of the plant

If triclopyr is absorbed into the leaf, it either
causes injury or is metabolized. Movement of
triclopyr is dictated by whether the plant is
actively growing and moving sugars out of the
leaf. Triclopyr is, therefore, termed phloem
mobile and tracks with the flow of sugar. If the
leaf is exporting sugars, then triclopyr will likely
be moved out with the sugars, and subsequently
accumulate in those tissues that are the sugar
sink.

We do not know exactly how triclopyr affects
plants. However, we do know that triclopyr
causes uncontrolled growth, resulting in twisting
of stems, curling of leaves and sometimes split
stems. Some theorize that triclopyr is so similar
to the growth regulator auxin that the plant
becomes overloaded with this growth hormone
and essentially grows itself to death. Other
researchers suggest that triclopyr make the cell
walls loosen, inducing uncontrollable cell
elongation. Further work in this area has also
shown excess RNA and DNA biosynthesis,
leading to the thought that this stimulates excess
cell division.

Regardless of which theory you believe, the
bottom line is that some cells of the plant growth
more rapidly than others. This results in cells
that grow unevenly, with some cells/tissues










getting crushed and destroyed in the process.
The vascular system is disrupted, blocking water
flow and sugar movement; ultimately leading to
plant starvation and death.

Triclopyr has limited soil activity and does not
persist for a long time in the environment. As
mentioned previously, most tolerant plants
(grasses) are able to metabolize triclopyr very
rapidly into non-toxic compounds.

Greg MacDonald

Progress of EPA's Review of All Pesticides

The 1996 Food Quality Protection Act (FQPA)
has required EPA to review all pesticides every
15 years, including ones that have been
registered in the past and are still being used by
applicators. Reregistration Elgibility Decisions
(REDs) are then published for each reviewed
pesticide, outlining the risk mitigation measures
and any changes to the pesticide's uses, crops,
label, etc. Organophosphates and carbamates
were the first group of pesticides targeted under
FQPA.


As 2005 ended, a number of risk assessments
and REDs were published as part of the
extensive reregistration process under FQPA.
Some of the remaining organophosphates and
carbamates are being reviewed and risk
mitigation measures put into place. EPA has an
online document on pesticide reregistration
status. It provides the status of all pesticide
active ingredients in the review process. Details
on active ingredients are available via EPA's
Fact Sheets. Another quick access route to
online information about pesticides on the EPA
website is their "A Z Index." The entry point
for these and all pesticide-related topics is at
EPA's Office of Pesticide Programs
http://www.epa.gov/pesticides/


Fred 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.
Preparedby: J.M. Bennett, Chairman; M.B. Adjei, Forage Agronomist .i... ii, 1i ,i ..i, J.A. Ferrell, Extension Agronomist
Si. .II, .i ,.1l -.h.i F.M Fishel, Pesticide C -.1.. ..1I --.. .I.I, .i ,,1 .1, i C.R. Rainbolt, Extension Agronomist
,11 ....h..11 i i ,, .1., B.A. Sellers, Extension Agronomist III I, .1 ,,11 .1..I D.L. Wright, Extension Agronomist (dlw@ifas.ufl.edu).