Group Title: Agronomy Notes
Title: Agronomy notes
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 Material Information
Title: Agronomy notes
Uniform Title: Agronomy notes (Gainesville, Fl.)
Physical Description: v. : ill. ; 28 cm.
Language: English
Creator: Agronomy Department
Florida Cooperative Extension Service
Publisher: Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida
Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida.
Place of Publication: Gainesville
Publication Date: September 2010
Copyright Date: 2010
Subject: 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 )
Statement of Responsibility: Florida Cooperative Extension Service, University of Florida, Institute of Food and Agricultural Sciences.
Additional Physical Form: Also available to subscribers via the World Wide Web.
Additional Physical Form: Electronic reproduction of copy from George A. Smathers Libraries, University of Florida also available.
General Note: Description based on: January 1971; title from caption.
 Record Information
Bibliographic ID: UF00066352
Volume ID: VID00127
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: alephbibnum - 000956365
notis - AER9014

Full Text


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 ivithout 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/LUniversity of Florida/1Villie Ferrer-Chancy, Interim Dean.

"Agronomy Notes" is prepared by: Maria Gallo, Interim Chair and Y. Newman, Extension Forage Specialist ..t ..!II. .1.... J. Ferrell, Extension
W eed Specialist l.. .IIl..t..~I I~ ..I. Fred Fishel ....Is. .I I ..I~g. i .>ward Frank I l _s! l.. ..II ..I....J. larois, Plant Pathologist I!~! .. ...t..~~ I I~~..I..ark
Mossler .I !I I .I......i..I I..I. Brent Sellers II. i 1...1.11.. 1... ~ ~. D. Wright, Extension Agronomist !!_!lng~ ~ .I I..In 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.

Fettures :

Crops :
Defoliating Cotton ......................................... Page 2
Hardest and Inclement Weather .................. Page 3
Peanut Grades ............ ........................... Page 2
Soybean Diseases and Soybean Rust .................. Page 3


Watch-out for Fall C ~.'.: t. in Pastu~res......... Page 6
What Bahiagrass Mlole C ickEet Damage
to Look for in the Fall................................. Page 7

Ba~yer Agrees to Terminate All Uses ofAldicarb
............................ Page 5
Weed Sdence Website..................................... Page 4

Miscel** ** ********
Calendar ....................... .................... Page 8

Crops Dr. David Wright, Extension Agronomist
Norz Florida REC, Quing,

Peanut Grades

Harvest timing is critical to high peanut grades and yield. Foreign matter and shelled kernels are usually an
indication of improper peanut picker adjustment. Foreign matter comes from screens being too open allowing
foreign material into the peanut stream or harvesting improperly cured vines or during conditions that are too
damp to blow foreign material through the combine. It may also be an indication of lack of weed control
during the growing season. Loose shelled kernels is the percent of peanut which have been shelled during the
harvest process which may be due to too high picker speed or too much air blowing peanuts against something
sharp in the combine or the picker fingers being set too aggressively.
If a peanut grade were 73% SMK and 2% OK for a 75 grade, the other 25% would be shells. Some peanut
varieties have thicker shells and will have lower grades than other varieties. Many growers may start digging
too soon if they have large acreages and the first few loads of peanuts will grade in the upper 60's or low 70's.
This can be caused by digging too early or having periods of drought when pegs did not set and a crop was set
early and one later when moisture returned making it difficult to determine when to dig with both very mature
and immature pods would occur on the same plant. Irrigated peanuts are usually easier to determine proper
digging date since moisture can be supplied for a continuous set of peanuts. Other factors like disease control
and weather conditions can determine digging date and these often cause yield losses. Vines should be kept
disease free as much as possible in case weather forces you to delay digging by a week or more and healthy
vines will retain mature peanuts better than dying, diseased vines. A week early or late digging peanuts can
make 500 lbs/A difference or more in yield and several points in grade. Five hundred pounds of peanuts are
worth about $100-125 and the difference between a grade of 69 and 75 on a 4000 lb/A peanut crop is worth
about $50-60. Many growers now used GPS to ensure that they are digging exactly over the row since data has
shown that as little as a 2 inch movement off the row can result in a 200 lb/A loss in yield. A key for high
yields and profit is to keep vines healthy and dig on time.

Crops Dr. Ddaid Wright, Extension Agr/onomist
Nodrz Florida REC, Quing,

Defoliating Cotton

Defoliation timing is often based on percent open bolls,
nodes above cracked boll (NACB) or heat unit
accumulation after cutout. Defoliation should be planned
two weeks in advance of harvest. If it will be longer
before harvest, defoliation should be delayed. Generally,
once the NACB reaches 4 or the field is greater than 60 to
70 open, cotton should be defoliated to prevent quality
loss from weathering. Which defoliant to use is difficult
to determine. A defoliation guide can be found in EDIS at
http://edis~ifas.ufl .edu/an l88 This guide gives many
different scenarios that can be of help under different
weather conditions.

Proper defoliation leads to good picking conditions.
Photo by David Wright.

Crops Dr. David Wright, Extension Agronomist
North Florida REC, Quing,

Harvest and Inclemtent W/eather

Growers experienced a difficult harvest season in the fall of 2009 due to rain as soon as harvest began through
early 2010. It is critical that there is enough harvest capacity to get a peanut crop in. Within a week of the time
when peanut is ready, it should be harvested or yield losses of 200-500 lbs/A may occur after that.
Furthermore, the entire crop can be lost with a 4 week delay. Due to peanut being an underground crop and
dependent on keeping the vines healthy until harvest, peanuts always have a precedent of being harvested first
ahead of cotton, soybeans or other crops. Harvest capacity is critical for peanut and also for cotton. Southeast
cotton has had quality problems, and timely defoliation and harvest are critical to keeping the quality high and
preserving the yield. Late season hurricanes can cause tremendous losses in lint and quality. Some of our
growers will Einished up harvesting in January of this year knowing that quality and yield was lost. Timely
harvests are just as important on cotton as peanuts and the work load should be managed to harvest both on

Crops Dr. David Wright, Extension Agronomist
No7r~th Florida REC, Quing

Dr. Jim Marois, Plaznt Pathologist

Soybean Diseases and Soybean Rust
Soybean rust infection in kudzu was knocked back in the winter of 2009-2010. The cold winter of 30
consecutive days below freezing was a record which we thought may have knocked the disease from the
continent but it has been found in kudzu in
many of the counties across North Florida v.
once again. Inoculum had built up each year ->h *cF:-YI
with more infected kudzu sites since it was
first found in the late fall of 2004. It had:
impacted soybean yield in some areas each of
the last few years and fungicides were 7
effective in controlling it. We believe that it .
may take 2-3 years for the inoculum levels to ..
reach the point that it had gotten to in 2009
and the impact to soybean growers. We have
learned how to control it over the past 5 years
and have a good base knowledge of what it
may do if the levels increase again. As to this
point this year, no rust has been found in
soybeans so it may not impact yield this
year but growers should still be diligent Soybean rust pustules on the underside of the leaf. No yellow halos.
since other diseases can cause yield losses Photo by David Wright.
in soybean and at prices of $10/bu, it does
not take much increase in yield to justify an application of fungicide. Weather conditions this fall will determine
the spread and spore buildup for this coming year. Periods of dry weather this fall will slow down the spore
build up.

Weed Science Dr. Jason Ferrell, Extension Weed Specialist
Dr. Brent Sellers, Extension Weed Specialist

Weed Science Website

For each discipline there are dozens of extension publications that cover many topics. But finding the one
publication you need, when you need it, can be difficult. To help address this issue we have developed the
University of Florida Weed Science Website (ww Iftee) cm)

This website is divided into three general sections: recommendations, fact sheets, and slide presentations. The
recommendations section contains information on all crops or areas where herbicides will be applied (turf,
vegetables, aquatic sites, agronomic crops, etc) while fact sheets cover information on specific weeds.

The section titled Slides' contains numerous PowerPoint presentations that are available for download. The
purpose of these presentations is to assist county faculty programming with the most current information.
Additionally, the Technical Training section contains automated, voice-over presentations that were developed for
teaching important concepts related to weed control. Please watch these modules and provide feedback toward
their usefulness. Also, if additional topics or information is needed, please notify us and we will attempt to get
that material added.

We hope this website provides useful information in an easy to navigate setting.

_ _

Weed Control Dr. Fred Fishel, Pesticide Information Director
weeddr(aluf .edu

Bayer Agrees to Terminate All Uses of Aldicarb

/""1I Ba ver CropSience

-c~ 7 he U.S.Environmental Protection Agency and Bay~er CropSciencee the manufacturer, have
aI reached an agreement to end use of the pesticide aldicarb in the United States. A new risk
assessment conducted by EPA based on recently submitted toxicity data indicates that aldicarb, an
upo i N-methyl carbamate insecticide, no longer meets the agency's rigorous food safety standards.
To address the most significant risks, and most significantly to Florida's agricultural industry,
Bayer has agreed first to end aldicarb use on citrus and potatoes and will adopt risk mitigation
measures for other uses to protect groundwater resources. New measures to protect shallow drinking water wells in
vulnerable areas of the southeastern U.S. coastal plain and lower application rates will be immediately added to product
labels for use on cotton, soybeans, and peanuts.

The company will voluntarily phase out production of aldicarb by December 31i, 2014. All remaining aldicarb uses will end
no later than August 2018. Additionally, EPA plans to revoke the tolerances (legal pesticide residues allowed in food)
associated with these commodities.

Aldicarb is registered for use as a systemic insecticide and nematicide on agricultural crops, and is formulated and marketed
solely as a granular pesticide under the trade name Temik. During the phase-out, the pesticide will continue to be registered
for use on cotton, dry beans, peanuts, soybeans, sugar beets, and sweet potatoes. Aldicarb products are not intended for sale
to homeowners or for use in residential settings. A restricted use pesticide, aldicarb may be applied only by trained, certified
pesticide applicators.

The memorandum of agreement and the agency's updated dietary risk assessment and supporting materials will be available
in the aldicarb reregistration docket, EPA-HQ-OPP-2005-0163, and in the aldicarb Special Review docket, EPA-HQ-OPP-
2006-0197, at

More information: htto://www.eva.aov/ovesrrdl1/REDs/factsheets/aldicarb fs.html

Dr. Yoana Newman, Extension F~orage Specialist

Dr. Mark Mossler, Pesticide Information

Malathion 57% EC 2 pints per acre INone No restrictions

Sevin XLR 1 to 1.5 quarts/acre 14 days for hay or grazing Two (2) or less per year

Lannate LV %/ to 3 7 days for grazing No more than 4 applications per year
pints per acre 3 days for having
Dimilin 2L 2 fl oz per acre/cutting INo restrictions for grazing No more than 6 fl oz per year. Cannot
1 day for hay apply more than 2 fl oz per acre/cutting
Tracer 1-3 fl oz/acre 3 days for hay or until it
has dried if grazing
Baythroid XL 2.6-2.8 fl ozlacre none No more than 4 applications per year
B.t. See label none Inone

Coragen 3.5-5.0 fl oz/acre None No more than 4 applications per year
Karate 2.6-3.4 fl oz/acre 0 days for grazing No more than 3 applications per year
7 days for having
Mustang 3.0-4.0 fl oz/acre INone No more than 5 applications per year
* This information is for preliminary planning purposes only. Be sure to always read and follow pesticide labels and
guidelines for any product you plan to use.
**Thanks to the UF/Pesticide Information Office for their assistance on product update.

Fall Arm~y Worm, Adu~lt (left) and Larvae _;
>.4Photos ly Lyle Bu~ss.

Watch out for Fall Caterpillars in Pastures
Ranchers and hay growers need to be watching out for caterpillar presence,
armyworms (Spodoptera sp.) and loopers (M~oscis sp), given the present weather
conditions. The best time to check (and to spray) for these insects is either early in
the morning or close to sunset, at which time they are most active. By walking
your pastures frequently you will be able to detect their presence when they are
small and easy to control. A product like Dimilin 2L (which is an insect growth
regulator that disrupts the normal molting process of the insect larvae) with
residual effect is recommended only when the worms are small (1/2 inch or Looper I.\ . < spp.)
smaller) and before populations build Due to the mode of action, Dimilin 2-L is Photo by, Yoana N~vewman,
slow to control, and signs of control with this product may not be seen until 5 to 7
days after treatment. If needing to control worms in less than a week other products should be used (see Table
below). If infestations are already in place try grazing the affected area before treating.

Product*c, ** k

Restrictions (waiting time
prior to utilization)

Maximum number of applications



~Forage Dr. Yoana Newvman, Extension Forage Specialist
Dr. Howard F~rank, Entomologist
jhfrank @uf .edu

What Bahiagrass Mole Cricket

Damage to Look for in the Fall? i

In September, look for galleries (horizontal tunnels just below:
the surface), churned up soil, and patches of yellow grass that f
later turns brown before completely dying--caused by the new
adults and the developing nymphs.

Mole crickets are active in the fall as well as spring, and can e
substantially reduce forage production in pastures and hay Hields
in Florida by tunneling of the sod. They feed on leaves and FieldApplication ofBenefdzal Niematodes for biological con-
stems ofbahiagrass but mainly on the root system. Roots trol ofllole CrickEets. Photo by, How~ard Frank.
damaged by mole crickets cannot provide the necessary support
and cannot take up water and nutrients to nourish the plant,
causing death of the roots and over time the affected bahiagrass
stand. The most harmful of the three pest species is the tawny
mole cricket, Scapteriscus vicinus, and the notes below refer
to that species.

Dr. Howard Frank, entomologist and expert on mole crickets
describes the following life cycle for this pest: with the
beginning of the spring, usually in March, the female insects fly
while the males make tunnels and sing to attract females. The
females lay eggs in April and May. Eggs incubate for three ,
weeks, whereupon nymphs (which look like tiny adults but
have no wings) start hatching and developing. The nymphs feed Detail ofApplication Rig. Photo by, Yoana Nie2wman,
and develop from May through early September, whereupon
many of them become adults (a few spend the winter as large
nymphs). In cold weather, mole crickets become inactive deep
underground, but they will still move close to the surface and feed during warm spells.

The only commercial control available and recommended at this time is to treat using beneficial nematodes
(Nematac is the commercial product from Becker Underwood) that kills pest mole crickets. The product Nematac is
best applied subsurface using a chisel rig when the soil is wet. (see extension publication EDIS # ENY 663/ IN413).
Or, a boom sprayer may be used when the soil is completely soaked, or during rain. The nematodes should be
applied in strips (apply one strip, skip seven, apply one, etc.) across a mole-cricket-infested pasture, because the
nematodes are alive and will fill in the untreated strips in about six months.

A parasitic wasp called Larra bicolor that was first released in Alachua County has now spread to almost all
counties in central and northern Florida. This wasp provides some level of free biological control of pest mole
crickets wherever it occurs, and eventually should spread everywhere in Florida. The wasp gets its energy by
feeding on nectar at flowers of certain plants. These plants include Spermacoce verticillata (shrubby false
buttonweed or larraflower) and Chamaecrista fa;sciculata (partridge pea). Propagation of these wildflowers will
benefit the wasp (see extension EDIS publication EENY-268).

,* .

1' "Strengthening the Goat Indusr~y"
*, September 12-15'".2010
http://wwafamu.edulgoats r
'., ,**
*.,r ,*

Sponrsorec$ by: L5F AFAIS, Center for Tropical Algricultrare (CTA)J LASDA TSTAIR f APHilS PPC2

To followed the link, press "CCtrl"J and put cursor ovler link, and "click."

Sept. 12-15 National Goat Conference, Leon Civic Center, Tallahassee

Sept. 14-17 International Citrus & Beverag~e Conference, Clearwater Beach

Sept. 16 Florida Equine Institute and Allied Trade Show, Southeastern
Livestock Parillion, Ocala

Sept. 23 Perennial Peanut Field Day North Florida Research and
Education Center, 9:30 am, Quincey

Oct. 5 9th Annual Fall Field Day and Open House--North Florida
REC http~:/ /

Oct. 12 Ona Field Day http~:/ / /
Ona REC, Ona

Oct. 11-14 UF-CTA Potential Invasive Pests Workshop,
Coconut Grove (Mliami), Mayfair Hotel


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