By Jerry Volesky and Ben Beckman
Fall Grazing of Alfalfa
Every fall, there can be some situations where there can be the potential to graze alfalfa. In some cases, the alfalfa may not have been big enough to warrant haying or maybe you have an alfalfa field that is adjacent to some cornstalks. A side benefit is that grazing alfalfa in late fall or winter can reduce alfalfa weevil infestations by removing stems and plant parts that serve as a wintering site or a spring laying site for weevil eggs.
Even through late October and into November, alfalfa is still quite green, despite several nights with low temperatures in the 20s. There may be some wilting and yellowing, especially on the top, but most leaves still are attached to the plant stems.
The real question often being asked is, “Can I be sure my cows won’t bloat if they graze my alfalfa?”. To be quite honest, you can never be 100% certain that alfalfa won’t cause bloat. Bloat occurs in ruminant livestock when gas produced during fermentation becomes trapped inside the rumen.
Bloat risk is much lower a week after a hard freeze that causes wilting. But always use good management methods to reduce the risk further. Have cows full before turning out to alfalfa. Wait until midday, after frost or dew is gone, before turning out. Provide other dry, palatable feeds or even bloat retardants. And keep a close eye on them for the first couple days.
Alfalfa can be grazed safely. Just be careful and realistic.
Soybean Residue for Forage
Bean fields are opening up after harvest and cows may be moving in to get them off pasture when other forage options are unavailable. Soybean residue or stubble can occasionally be baled and used in rations. Before we use it however, we need to set expectations. Is soybean residue a quality forage?
Soybeans themselves are very high in protein and fat. They are about 40% crude protein and about 20% fat, which is why soybean residue can be perceived as great feed. With such a high fat content, too may beans can cause issues with the rumen, so any spilled piles should be cleaned up before animals are sent out to graze.
Soybean residue itself, however, has a much different feed composition. The empty pods and stems contain only 4-6% CP and the TDN is only 35-45%. The leaves are slightly higher in protein at 12% but break down quickly after plants reach maturity and harvest has taken place.
These feed values will not begin to support the nutritional requirements of a dry cow even if there is some grain left in the field. So, while soybean residue can be grazed and can be used to move animals from overused pasture, supplemental feed is required.
When baled, soybean residue can be worked into a ration as a roughage source if other sources are less available. Just like grazing, baled soybean residue does not even come close to providing the feed value of cornstalk bales. Producers should also consider if removing litter from already lightly covered bean fields is worth the effort and potential erosion risks.
Source : unl.edu