Welcome!
July
24, 2012
DROUGHT
ISU EXTENSION DROUGHT
WEB PAGE
ISU Extension is
compiling resources on a web site to help you deal with the drought. Resources on
the web site are provided under various categories: Crops,
Livestock, Dealing with Stress, Home and Yard,
Financial Concerns, and Tips for Businesses. More
information is being added daily. Local educational events dealing with the drought
can also be found on the page which is at http://www.extension.iastate.edu/topic/recovering-disasters.
Along with the
drought web page, stay tuned to articles posted on the ICM News: http://www.extension.iastate.edu/CropNews/.
And the ISU Extension
Home Page also is focusing on drought issues http://www.extension.iastate.edu/.
ISU
Extension will also be conducting a drought webinar; see the For Your Calendar
section.
CORN
If Chopping Drought
Stressed Corn:
1.
Test for nitrates.
Corn that is stunted and has no ears from drought is the most likely to have high
nitrates, assuming normal nitrogen fertilization. The greatest risk is when the corn is
green chopped and fed directly out of the field. Ensiling will take care of much of the
nitrate problem. Leaving the lower 12-18 of the stalk in the field will reduce the
problem since nitrates tend to concentrate in the lower stalk. A rain a few days before
chopping tends to increase the problem. Before feeding send a sample to the lab to have it
tested. A list of some forage testing labs can be found at https://store.extension.iastate.edu/ItemDetail.aspx?ProductID=4421.
If you go through your local vet, samples can be sent to the ISU Diagnostic Vet Lab
(515-294-1950). Heres a fact sheet on nitrate toxicity and testing: http://www.iowabeefcenter.org/Forages_nitrate_toxicity.htm
2.
Test crop moisture for proper ensiling to insure
good fermentation. Good fermentation is important to reduce nitrate levels in the
feed. Dont be fooled by how dry the drought damaged corn looks. Most of
the corn is still probably over 75% moisture, which is too wet to just ensile.
a.
To determine
actual whole plant moisture:
1.
Sample some
representative plants from the field.
2.
Chop the plants, maybe run them through a chipper-shredder or other devise.
3.
Test for moisture
using the Koster moisture tester, or other method such as a
microwave oven or heat lamp. The microwave oven or heat lamp method is describe
in: http://www.extension.iastate.edu/Publications/RECOVERY14.pdf
4.
If the moisture is
over 70%, the problem then becomes how to harvest and properly ensile this forage.
The answer is easy, but to accomplish this is difficult. The answer is to add dry
matter to reduce moisture content. Air dry alfalfa or grass forage will decrease the
moisture content of wet forage approximately 5 percentage units for each 150 to 200 pounds
of material added per ton of wet forage weight.
CORN AND SOYBEAN
Foliar Diseases
In general there has
been less foliar disease this year, reducing the likelihood of a fungicide paying off.
Some have been
reporting Gosss Wilt showing up in some corn fields in the area again this year.
Fungicides have no affect on bacterial diseases like Gosss Wilt.
It was recently
reported that southern rust was found in corn fields in Butler and Grundy counties.
Southern rust spreads much faster than common rust and thus is potentially much more
damaging. Hot, humid conditions do favor southern rust development, and it is especially
concerning that it has been found this early in the season. If you find corn rust in your
field, it is much more likely that it is common rust, and thus not as much of a concern.
Fungicides are effective on both species. For information on how to distinguish between
the 2 diseases, see Allison Robertsons article at http://www.extension.iastate.edu/CropNews/2012/0716robertsonsalaau-rojas.htm.
FOR YOUR CALENDAR
Drought Webinar
July 25, 2012, 1-3
p.m.
Locally,
ISU Extension offices in Delaware, Dubuque, Henry, Jefferson, Johnson, Linn, and
Washington Counties will be hosting sites. See
http://www.extension.iastate.edu/article/webinar-examines-livestock-and-crop-options-during-drought
for more details.
Local Drought
Meetings Will
be Occurring over next 2-3 Weeks
See
the ISU Drought Page for Details
http://www.extension.iastate.edu/topic/recovering-disasters.
One that is not on
the list at this writing will be conducted at Buzzys in Welton (not Wilton) at 1:00 p.m., Monday, July 30, 2012. Crop and livestock management issues and options
will be discussed.
If you have any questions, please feel free to contact the Iowa State University Extension Office.
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