Alfalfa raised in Minnesota is both a hardy and fragile crop. It is designed to live several years, but is threatened by cold temps as well as too much or too little water.
The best way for farmers to determine the condition of their alfalfa is by getting out into their fields and really looking at the crop.
Even though fieldwork and livestock production can take up every minute of the day, it’s important for the farm manager to walk in the alfalfa fields – not just drive by.
Livestock operations that depend on alfalfa need a solid plan for obtaining enough alfalfa for their rations to last at least through the fall of 2013. If a lack of moisture or a stand concern develops, livestock producers do well to plan far ahead – either growing more corn or other feedstuffs or purchasing quality alfalfa when possible.
In southern Wisconsin, alfalfa farmers anticipated an early start for the 2012 first cutting – perhaps early May if temperatures remain above average. Moisture is adequate, and the alfalfa is growing.
“The alfalfa came through the winter in very good condition,” said Carla Fish, Croplan Genetics by Winfield, senior forage product specialist, of Madison, Wis. “The winter was mild with little winterkill.”
Despite the lack of snow cover, the temperatures stayed so mild that the alfalfa wasn’t affected.
One method for estimating yield potential on established stands involves counting the number of stems per square foot. If more than 55 stems are noted, the yield potential is good. Fewer than 40 stems indicate lower yield potential. Maximum yields occur in years two and three, depending on the variety type and grower management.
“Agronomists are making farm calls, and they are digging up the roots to evaluate the health of the plant,” Fish said. “Loss of forage yield and quality could be the result of keeping a less than optimum stand in – for one more year. Instead, consider rotating to corn and benefit from the nitrogen credit. Then seed new alfalfa.”
To analyze the root, dig out at least 6 inches of root, and then cut lengthwise to assess the root tissue.
According to Craig Sheaffer, University of Minnesota alfalfa and forage professor, healthy roots are firm and white in color. Roots with winter injury appear gray and water soaked.
“If 50 percent or more of the root appears injured, the plant will most likely die during spring green-up or later in the year,” he warned.
Syngenta alfalfa product lead, Brent Johnson, Minnetonka, said alfalfa broke dormancy early and the stands look great in Minnesota.
“I am unaware of any widespread injury reports,” he said, adding that Syngenta’s research facility, near Lacrosse, Wis., has no winterkill concerns at their alfalfa plots this spring.
There is one caveat, Johnson said. Should Minnesota experience a heavy frost and freezing rain, budded alfalfa could still experience a loss. A heavy frost on Easter 2007 caused significant loss to alfalfa stands that year.
Sheaffer agrees that Minnesota could do without a late frost in 2012.
“Basically the alfalfa is growing from buds that were formed last fall,” he said, adding that temperatures near freezing were not likely to hurt the crop. “If they were to freeze, then you would need new buds coming from the base.”
Sheaffer said the spring alfalfa plant is high in sugar concentrations that act like antifreeze to protect the crop. Alfalfa is hardier in the spring than in the middle of summer.
When planning new stands, Minnesota growers are leaning toward alfalfa varieties with Aphanomyces root rot Race 2 resistance, Johnson said. On poorly drained soils, the fungal disease kills seedlings or results in poor seedling development.
Given the mild spring, Johnson expected farmers to seed alfalfa in March and April.
“Soil conditions are good,” he said. “I would get my alfalfa in the ground, and hope for moisture shortly thereafter.”
At the Albert Lea Seed House, growers began picking up their alfalfa and small grains seed in early March, said Matt Leazitt, agronomist. He expected that most Southeast Minnesota growers would seed oats, barley or field peas with alfalfa.
“With the early warm weather, farmers are going earlier to planting,” Leazitt said. “We’ve been in a soil moisture deficit, so if the soil temperatures are right, conditions are right for a lot of farmers to go out and start planting.”