Late-planted soybeans that don’t mature before the fall frost can be salvaged as hay or silage, says Bruce Anderson, University of Nebraska extension forage specialist. He says soybean hay and silage can have feeding values very similar to alfalfa, at least when they’re made right.
“Start by harvesting soybean forage no later than when leaves start to turn yellow, before they drop off. It’s especially important to harvest before a freeze to prevent rapid leaf loss,” he says.
Soybean hay is challenging to make, as the leaves dry quickly and then become crumbly if raked, while the stems are quite woody and dry slowly.
Be sure to condition or crimp the hay to hasten stem drydown, Anderson advises, and avoid raking if at all possible.
“Soybean leaves crumble easy when dry, which will cause some yield loss and much lower feed value. If you must rake, like if you need to put several windrows together for baling, do it within one day of cutting,” he says.
Making good soy silage is less risky, if you have silage equipment and do it right.
“I prefer mixing chopped soybeans with corn or sorghum as they’re being ensiled, but that’s not always possible. For straight soy silage, first get a good, clean chop. Uniformly add a silage inoculant designed for legumes like alfalfa. In addition, add about 1 bu of rolled corn or 50 lbs of molasses to each ton of wet silage to aid fermentation. And pack soy silage especially well,” Anderson says.