Certified Crop Advisor Tom Kilcer titled his online July 2022 newsletter “Last Chance Forages.” He wrote that as we get to the beginning of August, especially across the northern tier of states and southern Canada, the temperatures start to drop at night and slow the production of the warm season crops (soybean, corn, sorghum, sudangrass, their hybrids and millets). As these warm season crops start to fade, cool season crops can thrive under these conditions. Stands of straight cool season grasses, if fed with nitrogen and sulfur, as well as adequate autumn rains, can give good yields in early October.
The key is that cool season crops will not dry fast in fall; thus, wide swath same-day haylage – and the proper inoculant – will make high quality forage. For those planting in early August, autumn-planted oats for forage has the biggest potential and is most practical. Planted at three bushels/acre of grain-type oats, one can expect to harvest two to four tons of dry matter per acre by the end of September, if planted in early August (for the Albany, NY area). Kilcer’s replicated research showed no increase for higher seeding rates. As planting is delayed, yields fall dramatically. The normally cool night temperatures of September conserve the sugars and produce forage with high fiber digestibility. With sufficient nitrogen plus sulfur, or manure, oats harvested as forage should easily reach 18% crude protein.
Fall oats are not a fool-proof crop. There are critical steps for success. Planting at the end of July or Aug. 1, especially in more southern areas, brings the risk that aphids introduce barley yellow dwarf virus, which can kill oat plants. Cool nights with heavy dew seem to knock down the aphids and reduce the potential for loss. Dr. Elson Shields of Cornell reported, “Since barley yellow dwarf virus is circulative, a neonic[otinoid] seed treatment will kill many aphids before they can transmit the virus – most of your problems would be in the disease area like rust.”
Dr. Gary Bergstrom of Cornell reported that rust populations in New York have developed the ability to overcome certain oat resistance genes, and they can now infect older, previously resistant varieties.
Scouts report having exited fields of susceptible oat varieties covered in rust spores looking like the orange highway cones. Presently on the market, there are resistant oat varieties called Steuben and Hayden. Developed by Dr. Mark Sorrells of Cornell, these varieties (for now) appear to solve the rust issue. The other alternative is scouting to apply a properly timed fungicide to control rust. Kilcer cautioned against planting late summer oats without fungicide. He mentioned a case where once they planted untreated oats at the end of July, and by the end of August that stand had totally succumbed to the rust. Neither Kilcer nor the three Ph.D.s cited above, advocate indiscriminate use of neonics, since these pesticides are known to be toxic to honeybees.
Let’s mentally leave late-summer planted oats in favor of winter forages – still referred to by many as cover crops. Triticale is a hybrid of wheat (Triticum) and rye (Secale), first developed over a century ago by Scottish and German plant breeders. For over 50 years the University of Nebraska at Lincoln (UNL) has managed a winter triticale breeding program to complement its winter wheat and winter barley breeding efforts. Winter triticale’s main reason for existence is to provide locally adapted feed grains in western Nebraska, where historically not enough grain is produced to feed local livestock. Of the fall-planted winter crops, triticale is less hardy than wheat. And rye is the most hardy winter cereal. Over time, it was discovered that winter triticale can function well as a forage or hay crop, as it produces more biomass than winter wheat or barley. UNL agronomists seldom compare winter triticale to winter rye, as the rye has a much greater tendency to produce volunteer plants the next year.
Generally in the Northeast, winter forages hit their optimum level of maturity (barely forming seed heads) between May 10 and May 20. This is usually 10 days before perennial forages on neighboring fields would yield the most digestible dry matter (DDM) per acre. Autumn-planted winter forages start waking up as the last snow finishes melting, while soil temperatures are still in the low 40s. So the triticale can be harvested, usually at 24 – 30 inches in height as soil temperature commonly hits the 50º F milestone – the same point at which corn can be safely planted.
In the much more immediate future, let us examine our winter forages again, be they rye, triticale, wheat, barley or speltz. These cold-footed crops serve well as a disposal site for manure applications during late autumn and winter. Most small grain experts believe that triticale can metabolize up to 70 pounds of nitrogen during the five-month period of November through March. Semi-solid manure averages about 1% actual nitrogen. An acre of triticale can be expected to process and store the nutrients from about 7,000 pounds of that manure over the five-month period (7,000 pounds/1%).
This math gets shaky when it comes to rye; because rye is taller than triticale, most agronomists recommend that growers limit nitrogen applications for Secale to 50 pounds during the November to March period. Because of rye’s height – one to two more feet than triticale – much extra nitrogen commonly causes lodging. Thus, presuming a typical 1% actual nitrogen in semi-solid manure, we should limit fall/winter pounds/acre of that soil amendment to 5,000 pounds. Moving forward to about Labor Day, I recommend growers plant the cheaper (compared to triticale) bin-run winter rye seed before planting the “grass seed” mixture next spring, because these “cold-footed” crop seeds can be planted into the disked-up winter rye sod. It’s a good idea to allow a week to 10 days to “mellow out” rye’s allelopathic (natural weed-killer) properties.