Double-digit annual alfalfa yields are within reach of Midwestern hay growers. Some are already quite close, says Richard Leep, Michigan State University extension forage specialist.
“We have growers here in Michigan who are consistently getting up to 8 tons/acre, and on some of their fields I suspect they're approaching 10 tons,” says Leep. Non-irrigated sandy loam soils won't produce such high yields, but loam soils with some clay and adequate fertility can, he adds.
Last year at the Michigan Ag Experiment Station, Leep and his research associates set a new yield record for non-irrigated alfalfa when three varieties — Garst 6415, WL 357 HQ and DKA33-16 — made over 10 tons/acre. Other varieties in the trial yielded from 5.3 to 9.5 tons/acre.
Michigan State researcher Milo Tesar set the previous world record of 10 tons/acre in 1980.
“That trial was conducted to maximize yield, so heavier-than-normal amounts of potassium and phosphorus were applied,” says Leep. “It was also located in an area that typically gets some storm runoff, so it had above-normal moisture.”
The record-setting 2005 yields were achieved without any special treatment, says Leep, who followed fertilizer recommendations from the university's soil-testing lab.
“We had good growing conditions last year, but I think the biggest factor that contributed to the 10-ton yields is the steady improvements that plant breeders are making to alfalfa varieties. Without good genetics, we would not have been able to take advantage of the favorable growing conditions we had in 2005.”
All varieties were harvested five times at the late-bud stage.
“We took four cuttings before Sept. 1, with the last one taken Oct. 20. That's the cutting schedule we recommend to our producers here in mid-Michigan.”
The alfalfa was established using the same management protocol that Leep and his colleagues recommend to growers. “We practiced what we preach,” he says.
The trial plots were established in 2003 at a seeding rate of 20 lbs/acre.
“That's a little higher seeding rate than most universities recommend, but it has resulted in very good stands for us,” he explains. “We used to seed 15 lbs/acre, but we seeded at higher rates around the borders. Over time, we found the border areas were better, so we decided to up the seeding rate. Establishing a good stand goes a long way toward getting high yields.”
Prior to seeding, he encourages growers to have their soil tested and to correct acidity problems.
“Request fertilization recommendations for your specific yield goals,” Leep advises. “If you have fields that can consistently reach 8 tons/acre, then fertilize accordingly.”
He says it's easier to get record-setting yields in research plots vs large fields. “There's much less variability among soil types in a small plot. In an 80-acre field, you may have several different soil types with varying levels of productivity. This is where site-specific soil sampling and fertilizer application may be useful and profitable.”