Prepared by: Joel DeJong,
Extension Field Agronomist
Plymouth County Extension
251 12th St SE
LeMars, IA 51031
Phone: (712) 546-7835e-mail:
Good corn and bad corn – Just travel around the counties in NW Iowa
and you can see a huge variation. Sometimes in the same field! But that
brings lots of problems with it, too. How do you harvest a field that has corn
that died a week ago, and with ears in other parts of the field three times
larger and yet to hit black layer? If it stays dry all fall, what is our risk for
field fires? The following are topics of some of the calls I have received
recently, with links to more information on each topic. I hope you find some
of them useful!
I continue to get questions on nitrates in corn. Remember that if it
was well fertilized and had little grain development these forages have
increased risk. All feeds (and bedding?) using cornstalks from stressed corn
should probably be tested for nitrate levels so management to reduce the risk
can be implemented. See "Nitrate Toxicity" which is published on the ISU
Drought Web Page.
I have had one call about a field that might have A. Flavus, the mold
that can potentially develop into Aflatoxin. I have not observed this as a
problem yet, but keep scouting for it! Learn more from this ISU ICM News
article from last week, or from the ISU publication on Aflatoxins in Corn.
A lot of acres have already been harvested for silage – many are on
soil that is somewhat sloped and now becomes more prone to erosion when
the rain resumes. Think about how we should manage crop residues this fall.
We might go nearly 9 months without good residue protection on some of
these acres. This might be the best time to consider cover crops to manage
this risk. Take a look at "Small Grain Cover Crops for Corn and Soybean,"
or this article from Wisconsin on "Getting Additional Forage This Fall," or
even this article from the Nebraska Crop Watch Newsletter titled
"Considerations for Late Summer-Planted Forage Crops."
Also, from the concerns at harvest questions – "Combine Settings
for Drought," and fire prevention tips for a dry harvest.
There is more out there that might be of help. Don't forget the ISU
Drought Page, and also more articles about issues like adjusting nutrient
applications for next year and a discussion of manure loss to tile lines in a
dry year that can be found in the ISU ICM Newsletter. Most questions I have
been asked have answers that can be found at one of these sites!
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