As alfalfa greens up, check what effects winter may have inflicted.
After a particularly harsh winter, forage producers need to get out to their fields to assess the health of plants as they break dormancy, says Keith Johnson, forage specialist with Purdue University Extension.
Forages in areas affected by below-zero temperatures during periods of no snow cover are most at risk for damage. Low-lying field areas where snow accumulated and iced over are also at risk for loss from suffocation.
"Get out there and observe those fields," says Johnson. "As the crop breaks dormancy, producers need to check to see if plant green-up is occurring. If that's not happening after several days with temperatures in the 50s and 60s, it's time for concern."
Although soils have stayed frozen for most of the winter in many areas, alfalfa growers still should pay attention to root heaving, he says. When some soils, especially those saturated and with some clay, go through multiple freeze and thaw cycles, alfalfa plants can be pushed up out of the ground.
Crowns and taproots should also be assessed. Johnson advises growers to slice into crowns of a few plants to see if bud tissues are cream-colored and green. "They also can inspect the root for cream-colored tissue. If they find dark brown tissue, that's not a good sign."
Stands with severe problems may not be worth saving, he says. If the problem area is limited to one large section of a field, it might be possible to seed something else just in that area.
If overseeding fields with thin stands, producers should consider using broadcast seeders on all-terrain vehicles.
He also advises looking carefully at soil fertility and residual overgrowth and developing a plan to fix any problems.
"Growers need to look for underlying issues that would cause seedling failure. Some of those issues include low soil pH and poor fertility. They need to make sure that residual growth from 2013 is no more than 4” tall so the seed can reach the soil surface.
"Also, overseeding alfalfa seed into a field that currently has alfalfa is risky because the alfalfa produces a chemical that hampers the establishment of new alfalfa seedlings."
Time any overseeding carefully. Broadcast seed at green-up so seedlings can compete with perennial plants breaking winter dormancy.