By Tracy Turner
Producers who take advantage of frost seeding now can expect to see greener, healthier pastures later.
Frost seeding, which is a method of broadcasting seed over frozen pastures to allow the seed to be incorporated into the soil as the ground freezes and thaws, is a less expensive way to renovate pastures for improved and increased access for livestock grazing, according to a forage expert from the College of Food, Agricultural, and Environmental Sciences at The Ohio State University.
Frost seeding is a good tool for producers to use in March during the transition between winter and spring because the natural freeze and thaw cycle occurring now helps to move the seed into good contact with the soil, said Rory Lewandowski, agriculture and natural resources educator for the College’s outreach arm, Ohio State University Extension.
“This week in particular is a great time for frost seeding with the temperatures forecast throughout the region to be at or below freezing overnight for the next several days,” he said. “We’ve got to get that freezing action at night because the contracting and expanding helps to move the seed into better contact with the soil.”
For best results when frost seeding, it important for the broadcast seed to come into contact with the soil, as the method will fail if there is too much forage residual cover and the seed gets hung up in that residue, Lewandowski said.
Typically, legumes are a better choice than grasses for frost seeding, with red clover and white clover the most commonly used legumes, he said. Other common choices include Alsike clover and Birdsfoot Trefoil.
Producers need to keep in mind the following seeding rates:
* Red clover: 6 to 8 pounds per acre
* Ladino or white clover: 2 to 3 pounds per acre
* Alsike clover: 2 to 4 pounds per acre
* Birdsfoot Trefoil: 4 to 6 pounds per acre
In addition to increasing the nutrient content and quality of a pasture, frost seeding also lessens the need for producers to add fertilizer, Lewandowski said. Legumes fix nitrogen typically in excess of their own needs, allowing the existing grass to use the extra nitrogen and improving their quality as a feedstuff, he said.
“There is no need to apply supplemental nitrogen once legumes become uniformly established and make up 30 percent of the stand,” Lewandowski said.
When frost seeding a legume species that has not been grown in the pasture for a number of years, producers should be aware of the need to include the proper bacterial inoculum to ensure that the bacteria responsible for fixing nitrogen become associated with the plant roots, he said.