August 21, 2003

 

Drought-Stressed Soybeans Can Make Hay, NDSU Specialist Says

With heat and drought baking pastures and soybean fields across the region, producers are wondering if they can harvest their withering soybean crop for hay.

"Maybe," says Greg Lardy a North Dakota State University beef specialist. "Many soybean herbicides have grazing and haying restrictions so make certain you know what’s been sprayed and what the restrictions are." Soybean plants can also accumulate enough nitrate, particularly under dry conditions, to cause nitrate poisoning. "Hay should definitely be tested before feeding," he says.

If the soybean plants can be harvested the hay is fairly high in crude protein, at about 15 percent or more. Total digestible nutrients are usually in the 50 to 57 percent range. Yields are typically less than three tons per acre.

"Soybean hay can be quite stemmy, so cattle may sort through it looking for the most palatable feed," Lardy says. "Because of the stems, the hay is often brittle and dusty. Grinding it and mixing it with other hay may be one option to consider."

The amount of stems in the hay also means bales don’t shed water very well. "That may not be an issue now, but if normal rainfall resumes in the fall, we could face some spoilage problems," Lardy says. He also notes that pods dry slowly. "Again, that may not be an issue now, but if wetter conditions occur as producers begin harvesting the crop for hay, they’ll need to make sure the pods are dried adequately

Experts recommend using a mower-conditioner to cut the hay to assure even moisture content and to minimize the loss of leaves. Soybean silage is not very palatable to cattle, so another grass crop such as corn or sudan grass should be added. Some research suggests that a 2 to 1 ratio of grass to soybean is optimum. Mixing with grass may also improve silage fermentation.

For more information see:

• http://ipm.missouri.edu/ipcm/archives/v13n20/ipmltr7.htm
• http://www.ansi.okstate.edu/exten/cc-corner/archsoybeanhay.html
• http://www.uwex.edu/ces/forage/pubs/SOYBNFOR.html

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Source: Greg Lardy, (701) 231-7660, glardy@ndsuext.nodak.edu
Editor: Tom Jirik, (701) 231-9629, tjirik@ndsuext.nodak.edu