Drought-stressed corn is prevalent in many areas of the state. Much of this moisture stress occurred during the critical developmental stages of pollination and early grain fill. Moisture needs for corn are high in these stages and severe moisture stress during this time can have a significant impact on grain yield and quality. In situations where pollination success was marginal or kernel development is poor, grain producers may be looking at using drought-stressed corn for forage.

Before harvesting the crop for forage, ensure that any pesticides used (including any herbicides, insecticides, or fungicides applied) allow utilization as forage and that any pre-harvest intervals are met. For example, if atrazine was applied to corn, label restrictions state to not harvest corn for forage within 60 days of application.

Be sure to check with your crop insurance provider before harvesting the crop for forage or your local FSA office for non-insured crops (i.e. blue corn).

Also, be aware of the potential for high nitrate levels in the forage and use recommended precautions in handling the forage before feeding it to livestock. Nitrates can accumulate in drought-stressed corn, particularly if stalks are barren. The lower 1/3 of the stalk typically contains the highest amount of nitrate accumulation. Dale Hicks and Paul Peterson of the University of MN report that the occurrence of drought during or immediately after pollination could be associated with highest nitrate accumulations.

Ensiling drought-stressed corn is preferred over chopping or grazing since ensiling can reduce forage nitrate levels. Be aware that although the crop may look dry, barren stalks may still contain 70 to 90 % moisture. Target a harvest moisture of 60 to 70 % for proper storage, which is the range normally targeted for corn silage. Safety precautions are also a must when ensiling drought-stressed corn since nitrous oxide, which is toxic to humans and livestock, is released in the ensiling process.

Testing of the forage is recommended prior to feeding to determine if there are any quality problems as well as to determine the nutritional value of the forage. If kernel growth is still occurring in the field, it will likely pay to wait with harvesting. This will allow for more grain fill, which will help increase forage yield and quality.

Several articles about feeding drought-stressed corn for forage can be found under “Dry Weather, Heat Wave, and Drought” icon on the U of MN Extension website at:

http://www.extension.umn.edu

The University of MN Extension Forages website also contains more information on the feeding of drought-stressed crops and forages in general, and can be found at: