Soil test for fertility needs. Water crop as you would for a grain crop, because you are interested in maximum accumulation of dry matter. Cereal forages greatest accumulation of dry matter is between late boot and soft dough. Magic Valley studies show accumulation of 2000 lbs.of dry matter per week. Oats, barley, triticale, and wheat are in descending order of acreage for commonly used cereals as forages.
Oats are prone to accumulation of nitrate if they are harvested under heat or drought stress.
If oats are the chosen forage, cut when they would need water. If they appear water stressed at harvest, it is advisable to have the nitrate level checked before feeding. Soil test for fertility levels, do not eliminate soil testing to cut costs in drought conditions. Add fertilizer as needed. Water short years are not good years to establish alfalfa crop.