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: May 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 )
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.
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
Bibliographic ID: UF00066352
Volume ID: VID00123
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


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Agronomy-Notes-May-2010-Issue ( PDF )

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IFAS Extension

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Exposure Of Bermudagrass Sprigs/Roots .......... Page 2

Pre-conditioning Bermudagrass Planting
M material ........................ ... ................... Page 3

Weed Control
Control OfAnnual Grasses In Bermudagrass ..... Page 4

USDA Releases 2008 Pesticide
D ata Summary ................................................Page 5

Calendar ............................................... Page 2

Prospective Students ~ Nov. 1 Application
D. ...: For Freshman Entering Fall 2010 .... Page 3

An exhibitor displays his entry at the Seminole Indian Youth Livestock
Show, April 1, 2010 on the Brighton Seminole Reservation near Okee-
chobee, FL. More photos from this event and the Alachua County 4-H
Youth and Livestock show are throughout this issue.

4-H Photos: Tyler L. Jones, IFAS Communications

4-H Livestock Shows (Photos) ........................... 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/Millie Ferrer-Chancy, Interim Dean.

"Agronomy Notes" is prepared by: Maria Gallo, Interim Chair and Y. Newman, Extension Forage Specialist -.. 1. I. .1.,. J. Ferrell, Weed Specialist
II. I. II. II 1.. i. F. Fishel, Pesticide Information Officer ... 1.1. .i1. .. R. Koenig, Undergraduate Coordinator II... .. ill 1..,, B. Sellers,
Extension Weed Specialist ( Designed by Cynthia Hight .. Iji', I .. 1, 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.


Dr. Yoana Newman, Extension Forage Specialist

Exposure Of Bermudagrass Sprigs/Roots

Never dig or cut more bermudagrass than
you would be able to plant in a day.

Leaving the material exposed to heat and
drying conditions dries the seed, and the
viability of the planting material is

Table 1 shows the effect of exposure time
during the day and how that exposure
reduces the viability of the seed.


To follow the link, press "Ctrl" and put cursor over link, and "click. "

May 5-7

June 2-3

June 6-8

July 11-17

Florida Beef Cattle Short Course
UF Gainesville, Hilton UF

SAF/SFRC Spring Symposium Sustaining Forests,
Fisheries and Aquatic Resources in a Changing World
Paramount Plaza Hotel, Gainesville

Soil and Crop Science (SCSSF) meets jointly with the
Florida State Horticultural Society (FSHS)
Plantation Golf Resort

Caribbean Food Crops Society meeting
Boca Chica, Dominican Republic

Brighton Seminole Princess at the Seminole Indian 4-H
Youth Livestock Show, April 1, Brighton Seminole
Reservation near Okeechobee, FL.

July 12-16 Greater Everglades Ecosystem Restoration Meeting, Naples

July 22-24

Southern Peanut Growers Conference,
Edgewater Beach Resort, Panama City Beach

July 31 Aug. 1 Florida Small Farms & Alternative Enterprises Conference
Osceola Heritage Park, Kissimmee

Aug. 1-5 Ecosytem Restoration Conference (NCER), Baltimore, MD

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

Exposure Time % Sprigs alive
at planting
No exposure 100
2 hours
(9:00 am to 11:00 am) 94
4 hours
(9:00 am to 1:00 pm) 72
2 hours
(noon to 2:00 pm) 30
4 hours
(noon to 4:00 pm) 3
8 hours, under shade and
moisture provided 100
(9:00 am to 5:00 pm)


Dr. Yoana Newman, Extension Forage Specialist

Pre-conditioning Bermudagrass Planting Material

Field ofpre-conditioned bermudagrass planting materials prior to cutting.

Photo: Y. Newman

If planning on planting bermudagrass hybrids using tops,
following are a few items to keep in mind:

SPlant tops only if you are cutting them from a nearby area.
Tops are more susceptible to desiccation than roots.

STarget summer rains for planting unless you have an
irrigation system that provides good moisture conditions.

SUse precondition material. Pre-conditioned material is a
nursery of bermudagrass planting material that is fertilized at
the initiation of rains using 100-50-100 lb/acre N-P205-K20
+ 2 lb/acre Zn, Cu, Mn, Fe and 0.2 lb/acre of Boron.

SAllow fertilized planting material to grow for a couple of
months before cutting them for -1 iriiit -, and if possible
apply 40 lb/acre of N to promote growing points (buds).

Prospective Students

Dr. Rose Koenig, Undergraduate Coordinator

Nov. 1 Application Deadline For Freshman Entering Fall 2012

Entering freshman at the University
of Florida have maintained an
impressive academic career in
preparing for college but sometimes
feel uncertain about selecting a major
because they lack understanding of all
of the career options that are
available to them. As an
Undergraduate Coordinator, I find
that many students are surprised to
learn the various jobs available for
graduates who possess a strong
background in the Plant Sciences. If
you are interested or you know of
interested high school students, then
please refer them to me to talk about
the Plant Science Major in the UF-
IFAS Agronomy Department.

June 5 is the
Next Test Date for the SAT.
Register at the link.

Undergraduate and graduate students with Dr. Rose Koenig examine wild sugar cane seeds in aplotfield at U.F.

Photo: TylerL. Jones, IFAS Communications


Weed Control Dr. Jason Ferrell, Weed Specialist

Dr. Brent Sellers, Extension Weed Specialist
Range Cattle REC Ona

Control Of Annual Grasses In Bermudagrass

The high temperatures and frequent rainfall of summer is great for bermudagrass growth, but it also creates ideal conditions for
annual grasses like crabgrass and sandbur. Crabgrass has excellent forage quality and can be ideal for !, I .il-,, but the delayed
drying time and off-color often causes problems for those attempting to produce high-quality bermudagrass hay. Sandbur can be
even worse by filling the bale with extremely sharp burs that can render the hay inedible.

Control of these grasses can be difficult to achieve. For several years it has
been rumored that Prowl H20 (pendimethalin) is close to receiving a
registration for preemergence control crabgrass and sandbur in
bermudagrass hayfields. Recently, this registration has been finalized. Prowl
H20 at 3 qt/A is highly effective on annual grasses, but must be applied
when bermudagrass is dormant. Though this application is relatively
expensive ,' /A) and carries a 45 day hay restriction and 60 day grazing
restriction, it will generally control annual grasses for 5 months or more.
Although we have missed our window for Prowl this year, it should be
something you consider for 2011.

It must be noted that Prowl H20 has no postemergence activity on weeds.
Crabgrass. Therefore, if weeds have emerged, other herbicides must be used. One
choice is imazapic (Plateau, Impose, etc). Imazapic is highly effective on
Photo: J. Ferrell several grass and sedge species, but can also be injurious to bermudagrass.

Generally f. l o ,in:, you can expect to see bermudagrass stunted for 3 to 4 weeks and this may result in the loss of one hay
cutting. Early season applications can be highly injurious, resulting in delayed growth for much of the season. To minimize this
impact, applications should not be made until the bermudagrass is actively growing and rainfall is common. Another strategy is to
apply imazapic after hay cutting, but prior to bermudagrass regrowth. This application pattern will reduce bermudagrass injury,
but may also reduce crabgrass control. Regardless of how imazapic is applied, proper use of this herbicide can result in premium,
weed free, bermudagrass hay.

Pastora (nicosulfuron + metsulfuron) is another, soon to be labeled, option for grass control. Pastora is effective on
johnsongrass, vasseygrass, and sandbur that is less than 2" in height. Pastora is not effective on crabgrass or goosegrass. If this
herbicide is applied to sandbur that is larger than 2" control is not likely, but the herbicide application will cause enough injury to
prevent the formation of the sharp burs. Pastora has also been shown to injure bermudagrass, but the injury is short-lived and
generally expected to be half as severe as imazapic. As stated previously, Pastora is not yet labeled for use in FL, but registration
is expected to occur within the next 30 to 60 days.

Another choice is to use glyphosate right after cutting. Glyphosate can be applied at 6 to 10 fl. oz/A immediately after hay is
removed from the field, but prior to bermudagrass regrowth. Generally f., 1i -i',; this application should be made within 1 or 2
days after hay removal (or 7 to 10 days after cutting). Delaying this application until bermudagrass regrowth has occurred can
result in bermudagrass stunting, but using low glyphosate rates as recommended here will generally not cause severe injury. The
drawback to this option is that total crabgrass and sandbur control is rarely achieved. These low rates, coupled with applications
to plants with little leaf surface area, results in fair levels of control. But, even if this application does not result in total weed
control, it will often stunt the weedy grasses and allow the bermudagrass to over-grow the weeds and shade them out. Also, the
relatively inexpensive application of glyphosate, while avoiding much of the bermudagrass injury issues associated with imazapic,
make glyphosate a highly attractive option.

Control of weedy grasses in bermudagrass hay can be problematic. However, we now have more options than ever. Although
there is not a "perfect" option listed above, there are many ways to now attack annual grasses in order to produce premium, weed
-free hay.

Weed Control Dr. Fred Fishel, Pesticide Information Director

USDA Releases 2008 Pesticide Data Summary

USDA's Pesticide Data Program (PDP) annually tests a wide
range of commodities in the U.S. food supply. PDP tests fresh
and processed fruit and vegetables, grains and grain products,
nuts and nut products, milk and dairy products, beef, pork,
poultry, catfish, corn syrup products, honey, pear juice
concentrate, barley, oats, rice, bottled water, groundwater, and
treated and untreated drinking water for pesticide residues. These
data are important to ensure the implementation of the 1996
Food Quality Protection Act (FQPA) is followed. The FQPA
requirements include stricter safety standards, especially for
infants and children, and a complete reassessment of all existing
pesticide tolerances. Twelve states participated in 2008, including
Harvestingfresh vegetables in south Florida. Florida. Sound conclusions about the U.S. food supply can be
drawn from the PDP results because these states represent all
Photo: F. Fishel regions of the U.S. and more than half the population.

During 2008, PDP tested 13,381 samples for various insecticides, herbicides, fungicides, and growth regulators. Of the 13,381
total samples collected and analyzed, 10,382 were fresh and process fruit and vegetables. The remaining samples consisted of
almonds, honey, catfish, corn grain, rice, groundwater, and treated and untreated drinking water. For fresh and processed fruit
and vegetables, almonds, honey, catfish, and rice, approximately 76.4 percent of all samples tested were from U.S. sources, 19.8
were imports, 2.7 percent were of mixed national origin, and 1.1 percent were of unknown origin.

Of the 11,960 samples of fresh and processed fruit and vegetables, almonds,
honey, corn grain, and rice samples analyzed, the overall percentage of total Us Pesticide Data Program
residue detections was 1.6 percent, with a range of 0 to 3.3 percent and a mean Anual Summary, CaLendar Year 2008
of 1.9 percent. The fruit and vegetables ranged from 0 to 2.2 percent with a
mean of 0.6 percent. The percentage of total residue detections for almonds was a
1.4 percent, for honey was 0.4 percent, for corn grain was 0.7 percent, and for
rice was 0.7 percent.

PDP laboratory operations are designed to detect the smallest possible levels of
pesticide residues possible, even when those levels are well below the safety
margins established by EPA. It is important to note that the mere presence of a
pesticide on food does not indicate the food is unsafe. For samples containing
residues, the vast majority of the detections were well below established
tolerances and/or action levels. Before allowing the use of a pesticide on food
crops, EPA sets a tolerance, or maximum residue limit, which is the amount of
pesticide residue allowed to remain in or on each treated food commodity. The
reporting of residues present at levels below the established tolerance serves to
ensure and verify the safety of the U.S. food supply.

Of all samples collected and analyzed, 67.5 percent were fresh fruits and
vegetables, many of which are often eaten in a fresh, raw state. Health experts
and the U.S. Food and Drug Administration agree washing fresh fruit and ..... .. -
vegetables before eating is a healthful habit. Consumers can reduce pesticide -
residues, if they are present, by washing fruit and vegetables with cool or Program cover shown; to read the entire program visit:
lukewarm tap water.

Photo: F. Fishel

4-H Livestock Show Photos

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Tyler L. Jones. IFIS Comm unications
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