The miracle fall forage crop
July 14, 2020
Who doesn’t like oats?
In 1930, there were nearly 40 million acres of oats harvested for grain in the United States. By contrast, the 2017 Census of Agriculture pegged harvested oat acres at just over 800,000. That is the definition of a drop in popularity.
Although we'll never reach the 40 million mark again, nor anywhere close to it, oats have undergone an impressive makeover as a relatively high-quality, high-yielding fall forage crop for the north and central latitudes of the U.S. and a winter crop in the South. Yes, it’s too early to start planting now, but it’s not too early to start planning for the additional fall forage that oats can provide.
What is most impressive about fall-grown oats is its harvest versatility. Chopping for oatlage, baleage, or grazing are all viable options. Dry baling is also possible with favorable weather, but more often than not, trying to get the crop dried down during the cool fall temperatures is a stress inducer.
A different animal
Don't think of late summer-sown oats in the same way you think of spring-sown oats. They're two different forages when cut near the boot or early heading stages. Whereas spring-sown oats begin under cool conditions and finish under warm temperatures, it's just the opposite for late summer-sown oats.
Oats harvested or grazed in the fall have significantly lower fiber levels, higher amounts of water-soluble sugars, and a much higher level of total digestible nutrients than spring-sown oats. Harvest timing is based on how the forage will be used. If being fed to lactating dairy cows, harvest in the early “boot” stage before seedhead emergence.
If the oats will be used for heifers or beef animals, waiting until after seedhead emergence will offer additional yield but slightly lower quality.
Planted in early August and harvested about 60 to 70 days later, oats can yield 2 or more tons of dry matter per acre. There are some risks with planting oats too early. Oats benefit from cooler night temperatures. Additionally, if planted too early in July, both diseases and insects can be an issue. Of particular concern are leaf rust and barley yellow dwarf virus, the latter of which is transmitted by aphids.
Plant fall oats at about 90 to 100 pounds per acre. Some producers choose to save money and use bin-run seed from a previous homegrown crop. Though this can be successful, it also comes with unknown seed quality and seed germination percent. Investing in a germination test from your state’s seed lab is a good preseeding investment.
A surer bet is to plant certified seed. This approach offers the opportunity to select an appropriate maturity or plant a variety bred specifically for forage. Many state universities now field test oat varieties and have shown significant differences in varietal performance.
Feed the crop
Ensuring an adequate amount of nitrogen is available to the crop is crucial to obtain high yields and forage quality. Many studies have demonstrated significant gains in crude protein concentration by applying nitrogen fertilizer. Oats grown on nitrogen-deficient soils will be a disappointment.
Generally, about 50 pounds of nitrogen per acre will be needed unless manure is applied prior to seeding or you know there will be carryover nitrogen available from a previous crop. Fields that have been extremely wet through the growing season will likely be very low in available nitrogen from denitrification or leaching losses.
Most university extension personnel can provide specific information for growing fall oats in the various states. Though the popularity of fall oats is growing, it still remains an underappreciated forage resource.