Table of Contents

Agronomy notes
Full Citation
Permanent Link: http://ufdc.ufl.edu/UF00066352/00106
 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: November 2008
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 )
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.
 Record Information
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: aleph - 000956365
notis - AER9014
System ID: UF00066352:00106


This item has the following downloads:

November%202008%20Agronomy%20Notes ( PDF )

( PDF )

Table of Contents
    Table of Contents
        Page 1
        Page 2
        Page 3
        Page 4
        Page 5
        Page 6
Full Text

IFAS Extension

Agronomy Notes

Volume 32:11


Cotton Defoliation ....................................................... Page 2

Ti//age for Cool Season Winter Annuals and Small Grains; and
W heat Planting ......................................................... ............. Page 2
Summer Sod Stubble and Winter Forages; and
Forages of Florida Website: a New Resource.................. Page 3

Weed Control
Wild Radish Control ............................................. ................ Page 4
Special Local Needs 24(c) Pesticide Registrations ...Pages 4-5

Calendar, Web Links, d Field Days ....................................... Page 6

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.

"Agronomy Notes" is prepared by: J.M. Bennett, Chairman and Yoana Newman, Extension Forage
Specialist (ycnew@ufl.edu); R. Barnett, Professor Emeritus ofAg (rdbamet@ufl.edu); J. Ferrell,
Extension Weed Specialist (lCnc! .11!1 c ...ii F.M. Fishel, Pesticide Coordinator
(weeddr@ifas.ufl.edu); and D. Wright, Extension Agronomist (wright@ufl.edu). Designed by Cynthia
Hight (chight@ufl.edu). Photos, except where designated otherwise, by Tyler Jones
(tylerljones@ufl.edu) in the UF/IFAS photo department. 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

November 2008

Cotton Defoliation

Cotton is defoliated to prevent staining the lint during the
picking operation. It should be defoliated before November in
most cases. When cotton is defoliated in November
temperatures are usually cooler and the defoliants do not work
well and higher rates have to be used.

Most of the cotton that is not opened
would have been set in September
and those bolls are usually smaller
and contribute little to final yield if -' '"'d ofcotton from the base after
the crop was planted timely and set defoliation andpicking.
an early boll load. Cotton should be
picked 2 weeks after defoliation since
regrowth will occur with favorable environmental conditions. Defoliants
normally contain ethylene which is a ripening agent that causes leaf drop
and bolls to crack open and fluff out so that cotton can be picked in one
Defoliated and non defoliated cotton has operation instead of two.
Sbe. pickeoperation instead of two.
not been picked.
_Photo.: D. Wright Dr. David Wright, Extension Agronon


Tillage for cool season winter annuals and small grains- Small grain may often respond to deep tillage
(chisel plow, etc). In most cases responses will occur in cool, wet conditions when nitrogen and sulfur
leaches below the root zone and a compaction layer prevents crop roots from growing through the layer.
We have seen as much as 15 bu/a yield increases on wheat due to deep tillage. Wheat prices are
predicted to remain high for several years due to the demand for grain for energy, feed, and food. No-till
production of wheat can work in some years but is often limited by root restrictions and water and
nutrient uptake.
Dr. David Wright, Extension Agronomist

Good wheat varieties were in short supply this past fall. However, there is a good supply of good varieties
for planting this fall. Wheat for grain can be planted from early November through the middle of
December. Some of the better performing varieties in Florida are AGS 2060, Pioneer 26R61, AGS 2000,
and SS 8641 which should be planted early. Other varieties that have done well in the Deep South are
Oglethorpe and AGS 2031 which both should be planted early, and AGS 2020. Some nitrogen should be
applied at planting unless it is being planted after peanut and the hay was left in the field. Many of these
varieties will yield best when planted in November instead of December. Seeding rate should be about 22
seed per foot of row in 7" rows. Many old and non recommended varieties were used last year since seed
were in short supply. That is not the case this year.

Dr. David Wright, Extension Agronomist Dr. Ron Barnett
North Florida REC, Quincy Professor Emeritus
wright@ufl.edu rdbarnet@ufl.edu

AgronomyNotes Pagl


Summer Sod Stubble and Winter Forages

Too often overseeding of winter forages on bahiagrass or bermudagrass does not have a successful out come as a
consequence of too much summer grass still present at planting time that interferes with the soil to seed contact
and establishment of the winter forage. Particularly susceptible to the tall stubble from the summer grass are the
clovers because of the small size of their seed. To avoid this situation the summer sod needs to be cut or grazed
short, usually to a 3 inch stubble.

Additional 'scratching' or very light disking (2 to 3 inches penetration of the sod) is recommended to break the sod
and enhance seed to soil contact. Make sure you don't overdo the light disking because, although the rhizome
systems of bahiagrass can take it, it will promote the growth of winter weeds as the sod/soil is disturbed. Winter
forages with large size seed, such as small grains (oats, wheat, and rye) and vetches can stand taller stubbles.
Some times burning the summer grass residue is used but is the less preferred option if mowing or grazing can be
done because of dry field conditions that prevail usually prior to overseeding time.
Dr. Yoana Newman

Forages of Florida Website: a New Resource

We have a new support tool for forage production! It is the F


I Search r; -
I B .'' e- ...7,. ) .... ':

> Florida Forage Plants Florida Counties Extension
Grasses Pause the mouse over a county in the map
Legumes county's name. Or, move the mouse over a c
Natives list below to find it on the map You may clic
orthe name to no to that count's home paa

w Management
Cover Crops
Fertilization & Liming
Planting & Renovation
Soil Nutrient Management
b Problems
Insects & Nematodes
Pesticide Regulations
& Safety
Toxicitles & Disorders
WpRd t Rrish


Hardee Okeecho
Hendry Orange
Hernando Osceola
Highlands Palm Be
Hilsborough Pasco
Holmes Pinellas
Indian River Polk
Jackson Putnam
Jefferson St John

oranges of Florida website:


There you will find information about:

Forage Plants Grasses,
Legumes, and Natives for Florida (with
.... ,- ..... visual resources), including description,
adaptation, and management
information tailored to Florida

IFAS Extension

offices Publications (EDIS) related to
belowto see the
ount name n the forage production from different
k on eitherthe map d i
e. disciplines.

Links to Forage Events
and extension events, as well as to
bee other forage related sites.
The site also features a map of Florida
with access to the different county
s extension offices and agents. Be sure to
add this link to your "Favorites."

Dr. Yoana Newman
Extension Forage Specialist

Agronomy Notes Pag


Wild Radish Control

With cooler temperatures approaching, it is time to start thinking about wild radish
control. Wild radish seed germinates when soil temperatures reach approximately
65 degrees and forms a rosette on the soil surface (see photo). At this stage, 2,4-D
is highly effective at rates as low as 1 pt/A.

Waiting to spray until yellow flowers appear make control much more difficult,
require higher herbicides rates, and likely will cause injury to winter forages
(ryegrass, oats, etc.) So start scouting fields every few weeks over the next month
and be ready to spray for wild radish. Early intervention will provide better control,
Wild Radish in the rosette require less herbicide, lead to less injury, and allow more winter grazing.
growth stage.
Photo: J. Ferrell Dr. Jason Ferrell, Extension Weed Specialist

I jferrell@ufl.edu

Special Local Needs 24(c) Pesticide Registrations

Consider the two following scenarios:
A new pesticide application technology has been developed
specifically for nursery producers; however, current pesticide
labeling does not support its practice. The new technology
could result in fewer pounds of pesticides introduced into the
environment and less applicator exposure.

An insect pest introduced into Florida during the 1960s has
shown continuous activity on vegetable crops. Producers
recently discover that a pesticide already in use for other pests
will also control this pest, but it or the crop aren't listed on the UFIFAS Photo: T. Jones
pesticide's label.
These scenarios have a common theme pesticides that have been in use over the years could be adapted to fit
unique production situations within the state. How can producers call attention to these situations and convince
state and federal agencies to allow special use of pesticides? By applying for Special Local Need Registration,
also known as a 24(c). Producers bring their situations to the attention of scientists at the University of Florida
and their respective commodity associations. In turn, these groups provide supporting evidence to the Florida
Department of Agriculture and Consumer Services (FDACS). FDACS forwards the supporting documents to the
U.S. EPA for review and consideration of use approval. With these groups working cooperatively, special local
needs labels are written specifically for Florida to address these unique situations.
A special local need means an existing or imminent pest problem has been identified by producers of a given
agricultural commodity within Florida. Major pieces of supporting information required for such a use is that the
24(c) use:
Is covered by necessary tolerances or other clearances under the Federal Food, Drug, and Cosmetic Act. A
tolerance is a term that is used legally to describe the amount of a pesticide's residue that may remain on or in a
treated crop according to federal regulation.
Registration for the same use has not previously been denied, disapproved, suspended, or canceled by the
Environmental Protection Agency (EPA), or voluntarily canceled by the pesticide's registrant. This can
occur because of health or environmental concerns about an ingredient contained in the pesticide product. If
new data become available that resolve the EPA's concerns, then a 24(c) may be considered_
Agronomy Notes

Special Local Needs 24(c) Pesticide Registrations

The 24(c) registration is in accordance with the intent of the Federal Insecticide,
Fungicide, and Rodenticide Act (FIFRA).

If the proposed use or product falls into one of the following categories, FDACS must determine that it will not
cause unreasonable adverse effects on humans or the environment:

Use of a product which has a composition not similar to any current federally registered product.
Use of a product involving a use pattern not similar to any federally registered use of the same product or
a product of similar composition.
Use of a product for which other uses of the same product, or uses of a product of similar composition,
has had registration denied, disapproved, suspended, or canceled by the EPA.

FDACS can consider uses such as the following for 24(c) registrations:
SNew method of application or timing of application.
SNew pest.
O Altered rate.
O Application in particular soil type.
SNew product/different formulation.
O Products useful in managing pesticide resistance in a particular crop.

A price differential between products is generally not viewed as a legitimate justification for a 24(c) registration.

FDACS can issue 24(c) registrations for the purpose of avoiding the buildup of pest resistance. Documenting this
need is met if:

> The pesticide with the 24(c) registration has a different mode of action from that already available; or if
registering two pesticides under a 24(c), they must have different modes of action.

> There are currently registered pesticides; however, there is only one effective mode of action remaining.

> The pest has a history of developing resistance to existing or canceled pesticides and this resistance is
documented through field studies or references to field studies.

> The currently registered pesticide has a history of resistance which is documented through field studies or
references to field studies.

> Evidence must exist that the pest(s), use patterns, and climatic conditions for the proposed use under the
24(c) is the same or substantially similar to situations where resistance has been documented.

> A brief description of the resistance management plan and how the pesticide's use under a 24(c)
registration will fit into the plan.

Applicators who wish to use a product in a manner approved by the 24(c) registration are required to have in their
possession a copy of the supplemental 24(c) label at the time of application as well as the Section 3 label. They
are also required to fully follow all applicable directions, restrictions, Worker Protection Standard requirements,
and precautions on the EPA-registered label.

For additional information, contact the FDACS Pesticide Registration Section. Telephone: (850) 488-3731. http://

Dr. Fred Fishel
Pesticide Information Officer
weerAgronomy Notes
weeddri cufl.edu

Oct. 29 Urban Farming Workshop Building Sustainable Communities
Seminole County Extension Auditorium, Sanford, FL.
Registration of $10 includes lunch. 407-665-5554, rvt@ufl.edu

Nov. 5 2008 Florida Ag Expo
Gulf Coast Research and Education Center in Balm, FL
Visit http://flagexpo.ifas.ufl.edu or contact Christine Cooley
(813) 634-0000 x 3101 ccoolev@(ufl.edu

Nov. 11-14 Methyl Bromide Alternatives Conference
Orlando, FL, http://mbao.org/

Dec. 3-4 National Organic Standards Training
Quincy, FL North Florida REC; contact: (352) 273-3508 jseftoni@ufl.edu

Feb. 1-3 American Society of Agronomy Southern Branch; Atlanta, GA

- I r

Dr. Lonnie Ingram addressing
attendees at the York i, ir, l, h,..
Lecture series.
UF/IFAS Photo: T. Jones

Ethanol demonstration at North Florida

Cellulosic Ethanol...Ethanolfrom Inedible Portions of

By the 24th York Distinguished Lecturer, Dr. Lonnie Ingram

Now available at: http://yorklecture.ifas.ufl.edu/

The 24th York Distinguished Lecture is now available for viewing and the following
equipment/software are recommended: Pentium 4 PC or higher; DSL Internet
connection speed or faster; Windows Media Player 9 or higher installed; and Microsoft
Internet Explorer browser.

Berry Vegetable Times newsletter from Hillsborough
Co. Extension and Gulf Coast REC

Chemically Speaking newsletter.

Entomology andNematolopy newsletter

Florida 4-H: A Century of Youth Success, a new
historical book available for sale.

Florida Master Naturalist Program newsletter

International FOCUS newsletter

Safety News & Notes newsletter.

S1,,,l/,i/ et Florida REC newsletter.

REC, Quincy Field Day. Sunbelt Ag-Expo live webcams.

Photo: T. Jones

Agronomy Notes Pag