Due to summer growing conditions that have been unfavorable for soybean production and the need for hay, an unusually large amount of hay has been made from failed soybean crops in several areas of Oklahoma.  Farmers and cattlemen in the state are relatively unfamiliar with soybeans as a hay crop and therefore, have questions about its use.  Following are some points about feedings soybean hay to beef cattle. 

1. Soybeans can make very good hay and have been used widely in certain areas for this purpose often substituting it for alfalfa or clover.  Soybean hay, according to 1984 National Research Council will be 17.8% crude protein, and 53% TDN, when sun-cured and harvested at mid-bloom. 

2. The requirement for protein and energy in the diet of an 1100 pound dry cow in the last third of pregnancy (.4 ADG) is 7.8% C.P. and 53% TDN, respectively.  If dry cows are given free access to high quality soybean hay, obviously protein is overfed.  Mixing with a good quality grass hay will suffice for most dry cows. 

3. A large percent (10-20%) of soybean hay is wasted during feeding due to the coarse stems.  However, the part that is eaten can be equal to average quality alfalfa in feeding value. 

4. If soybean hay is chopped (tub grinder), cows will eat practically all of it.  However, the stem is high in fiber and low in digestible nutrients.  It may be more economical to simply feed more hay and let the cows leave the stems.  Rarely, however, in a drought year will excess hay be available. 

5. When packaged as large round bales and left unprotected from the rain, it has been observed that rain will penetrate the bales much more than grass hay.  This can result in extreme storage losses, mold and refusal by cattle. 

6. Unlike other kind of hays, soybeans can have a good feeding value when cut at any stage from the time the pods are formed until the beans are almost fully developed and the lower leaves are yellowing, but before they drop off. 

7. When the soybean seeds are nearly full size at cutting, but still green, they dry out very slowly in the pods, and are apt to mold when the hay is stored.  Soybean hay that contains a high proportion of beans can result in a diet too high in fat resulting in scouring, depressed appetite, and digestive problems. 

8. Soybean plants are listed in the toxic plants of Oklahoma as a plant reported to accumulate nitrates.  Also, there is the potential for toxic weeds (i.e. nightshades) to be cut and baled with this hay.  Nitrate toxicity due to nightshade in soybean hay has already been reported this year in Oklahoma.  The chance of animals consuming harmful material would be increased by chopping the hay for the purpose of reducing waste.  If concern about potential nitrate accumulation exists, take a representative sample of the hay to your local OSU County Extension Office to be sent to the Forage Testing laboratory for quantitative analysis.