To determine feasible recommendations, let’s examine a few scenarios that might be options for beef producers. Provided herbicides used do not limit grass establishment, the use of summer annuals such as sorghum, sorghum X sudangrass, sudangrass, or millets, will provide the highest yields of forage for either grazing or mechanical harvest, as well as the widest window for grazing or harvest. These species can be grazed prior to frost, or well into the winter, with appropriate precautions in place for prussic acid poisoning between the first frost and killing freeze. They also can be chopped for silage or wilted for baleage; however, they are not recommended for dry hay harvest due dry down difficulties.
If herbicides prevent grass establishment until later in the summer, Schwab said producers might consider a mid-August seeding of spring or winter cereal grains such as oat, cereal rye, ryegrass, wheat or triticale, again with or without a legume or brassica. These are cool season crops and will grow better after the start of August rains and temperatures begin to cool. These produce a high quality grazing forage from grain harvest until well after the killing freeze if enough growth is present. The winter-hardy cereal grains will also provide early spring grazing prior to grain planting.
Regardless of the species selected, all will provide optimum feed if strip grazed to reduce waste. This can be accomplished with a single electrified wire moved weekly or twice per week. Start with the part of the field closest to the water source. Leave adequate forage residue for regrowth or protection from erosion.
Source : iastate.edu