By Allen Gahler
While some parts of Ohio have been rather dry this spring and into summer, other areas have been consistently wet throughout. Either scenario can cause significant problems for grazing and haymaking.
If you are looking for alternative forages to either graze or harvest for hay yet this season, oats are one crop to consider, in part because of its flexibility as a feed, yield potential and low-cost establishment. While traditionally planted as the first crop in early April as a grain crop or an early-season forage, one of the beauties of oat is its versatility in planting date.
Oats can also be planted in the summer through early fall for fall grazing or forage harvest. Summer oats have a wide planting window, but perform much better with an application of nitrogen and may benefit from a fungicide application to improve quality.
Options
Past forage trials conducted at the North Central Research Station in Sandusky County have examined the planting of oats from July 15th through late September to learn tonnage and forage quality possibilities. Through these trials, we have examined planting date, yield, forage quality and an application of foliar fungicide to control oats crown rust.
Usually, the best scenario for growing oats for forage is to plant them into wheat stubble, which is normally available by mid-July at the latest. However, the typical recommendation is to plant oats between Aug. 1-10 to maximize tonnage and quality, since the shorter day length triggers oats to grow more leaf rather than try produce seed.
But if you plant too late in the year, there is not enough time for growth, if you’re considering a hay or haylage harvest.
Nitrogen
As found in numerous previous studies, applying 46 pounds of nitrogen significantly increased yield on all planting dates from July through September, but applying 92 pounds only increased yield during the late July planting and again in the mid-September planting.
Adding this study to others, the recommended nitrogen rate for summer oat forage is to apply 50 pounds of nitrogen at planting. When planted in early September, yields fall to an average of a half-ton per acre, making it less economical to mechanically harvest as stored forage and more economical to graze.
Some validation has been given to applying up to 100 pounds of nitrogen in this case of September plantings, which has shown an economical advantage when plans are to graze those oats into the winter.
While oats will winterkill, it does take a significant amount of time below a temperature of 28 degrees Fahrenheit in order to completely stop growth. So, in the average year, oats will continue to grow well into November, and in some previous studies we have documented significant growth all the way through Christmas.
While haymaking at this point is obviously not realistic, grazing is still a good possibility.
Planting
Based on previous trials, we recommend seeding oats at 2-3 bushels per acre and applying 50 pounds of nitrogen at planting.
The most common source of seed used in Ohio is triple cleaned feed oats, and test weight is normally much higher than the standard 32 pounds, so a more accurate assessment for planting rate may be to seed 80-100 pounds per acre, regardless of the source. The oats should be planted into moisture up to 1.5 inches deep if needed.
No-till planting is the ideal seeding method, but shallow conventional tillage maybe required to incorporate nitrogen, assist with weed control and improve seed to soil contact if drills are not closing the seed slot.
Just keep in mind that if mechanical harvest is the intention, loose soils from conventional tillage may contribute to significant soil in the harvested crop, leading to higher ash content in the feed.
If weeds are present, a chemical application of Glyphosate plus 2,4-D can be used to clean fields up before planting or before oats has emerged.
Harvest and yield
When harvested as a stored forage, oats often need to be harvested as silage or baleage. If weather allows for dry harvest, the oats usually needs tedded multiple times and in late September or October, six or more days of drying may be required. Oats makes an excellent double crop after wheat.
When planted between mid-July and mid-August and fertilized with at least 46 pounds of nitrogen, average yields are in the range of 1-1.5 tons dry matter, and with ideal conditions, 3 or more tons is very possible. The nutritional value of oats without fertilizer is about $250 per ton of dry matter and when fertilized, the value increases to about $280 per ton.
Forage
Oats make excellent forage for sheep, goats, beef cows, feeder calves, dairy heifers and when made early, even milking cows. Planting after wheat harvest provides forage and increases farm profitability, with return on investment rivaling and often surpassing the potential for double-crop soybeans.
One of the few downfalls to fall harvested oats for forage is that they are very susceptible to crown rust, which usually settles in around 30 days after planting, regardless of planting date. In several trials over the last several years, fungicide applications have had no significant effect on yield but did affect forage quality.
The application of nitrogen also increased forage quality but only the mid-August planting saw a difference between 46 and 92 pounds of nitrogen for both crude protein and total digestible nutrients. The application of fungicide improved oats digestibility, increasing protein by 1-2% and energy by 5 points. Energy also saw a consistent increase over all treatments based on planting date.
Crude protein averaged around 14% when nitrogen was applied, but only 10% without nitrogen. Total digestible nutrients had an average of 50% with a nitrogen application and 40% without the nitrogen application. Oats fertilized with at least 46 pounds of nitrogen had visibly less effect from crown rust as well.
In summary, to gain some high quality, low-cost additional forage, specifically after a wheat crop, no-till 80-100 pounds of triple cleaned oats on or near Aug. 1, after applying 40-50 pounds of nitrogen per acre, then apply a fungicide approximately 30 days after planting, and expect to harvest 1-1.5 tons of dry matter in approximately 60-75 days.
(Allen Gahler is an OSU Extension ag and natural resources extension educator in Sandusky County.)
