Feeding drought-stricken soybeans or sorghum as forage requires close management. While they're good sources of needed livestock feed, they also can be toxic, University of Nebraska specialists said.

When used right, the drought-stricken forages are a good substitute for dry pastures, said Bruce Anderson, forage specialist in NU's Institute of Agriculture and Natural Resources.

Harvesting and feeding soybean hay or silage is similar to feeding alfalfa, he said. Harvesting sorghum for forage is similar to harvesting corn and it also can be made into hay or silage.

Feeding these drought-stressed crops is much like feeding other hay crops. Beef, dairy cows and sheep can use the fibrous nature of these drought-damaged plants, while swine can use it more as a filler, Anderson said.

Livestock can graze soybeans, but usually shouldn't graze sorghum because it is too high in prussic acid and nitrates, which are poisonous to cattle, Anderson said.

Soybean silage is best made with a moisture content between 60 percent and 70 percent, Anderson said.

A useful in-field method to test silage moisture is the squeeze test.

After chopping some forage, grab a couple of handfuls and squeeze it tightly for about 30 seconds. If it stays in a ball and the palm of the hand is moist, but not dripping wet, it's just right for chopping.

Forage quality drops quickly in soybeans after seed begins to form.

It should be harvested before the bottom leaves start to turn yellow, and cut earlier if possible because the stems become woody and poor in quality.

It's especially important to harvest before a freeze to prevent leaf loss, Anderson said.

"With soybeans we also have to avoid the loss of leaves," he said.

"They crumble easily. We just can't cut them when they start drying, or we'll get sticks."

To aid fermentation in chopped soybean silage, it may be best to mix in chopped soybean plants with corn or sorghum silage, Anderson said. A ration of 1 ton soybean silage to 3 or 4 tons of corn or sorghum silage will improve fermentation of the soybean silage and increase protein content of the corn or sorghum silage by 2 to 3 points. ©