Oats are also susceptible to barley yellow dwarf and smut. Weeds should be controlled early in the oat crop. Weeds will consume both soil water and nutrients required by the oat crop to reach maturity. Some annual, broadleaved weeds are also nitrate accumulators and their presence will increase overall nitrate problems. Heavier oat planting rates may not be the answer because with limited irrigation water, additional oat seeds will demand more inputs than likely available. The smallest oat seedlings will eventually die through self- thinning but some may survive and delay the development of the crop in a water short year.
Winter or red oats are commonly grown when oats are used for pasture. Winter oats are much less winter hardy than winter wheat or cereal rye. Red oats are leafier than common oats but if pasturing either oat type, delay grazing until oat plants are well established or when 6 to 8” tall.
Livestock can easily pull up the small oat seedlings if grazing occurs before the crop is established. Use a rotational system of grazing to move livestock before the oat is grazed to 3 to 4”. The goal is not to graze the primary (first) node off above the soil surface as growth will stop if the growing point is removed. Depending on weather and irrigation water, oats will regrow if proper stubble height is maintained and produce one or more grazing cycles. Grazing livestock should be monitored closely for nitrate poisoning. Symptoms of nitrate poisoning include a rapid and weak pulse, increased and painful breathing, staggering, eye whites and tongue turn blue, reduced feed intake, chocolate brown blood and finally death. Additionally, monitor livestock for grass tetany and milk fever as both conditions are possible when grazing lush, rapid growing oat pasture.