Frost seeding of legumes in February and early March can be used to improve pasture, hay quality and yield. The freezing and thawing of late winter and early spring can provide for good legume seed/soil contact and germination.
The following steps will help to ensure frost seeding success.
1. Site selection
Chose a field that is well drained and has been closely grazed. A thin sod will likely reduce competition and allow for seed to soil contact. In addition, a southeasterly slope will receive more sunlight and favor legume growth.
Animals will also help to trample seed for better soil contact. However, remove animals when germination of the seeded legume begins and keep them off these fields for four weeks after germination. This will allow forage plants a chance to establish a strong root system.
Soil pH should be 5.5 or above, with better legume growth at soil pH levels above 6.0. A soil test should have been taken and if needed, phosphate and potash can be broadcast by mid-May. Soil test kits are available at your local OSU Extension office.
3. Inoculate legume seeds
If the legume plant being seeded does not currently exist in the field, inoculate legume seed with the appropriate strains of nitrogen-fixing bacteria.
Remember inoculates should be stored in a refrigerator from the time of purchase to use. The rhizobia bacteria can be killed at high temperatures. Also, check the expiration date on the inoculate package.
4. Grazing management
Allow newly seeded legume plants to grow. Do not overgraze newly seeded plants. Manage grass height so as to allow sunlight to reach clover plants. Clover and other legumes are often the preferred forage species of grazing animals. For this reason rest periods between grazing may need to be adjusted to allow for adequate legume regrowth.
Use nitrogen in small and split applications, as excess nitrogen will likely cause grass to overcrowd and out-compete legume plants. A pasture or hayfield composed of 35 percent legume needs no additional nitrogen.
6. Selection of legume species and seeding rates per acre
a. Red clover and birdsfoot trefoil: 6-8 pounds red clover and 3-4 pounds birdsfoot. This combination provides good legume compatibility for cattle.
b. Red clover and ladino: 6-8 pounds red clover and 2 pounds ladino. This combination will support grazing for goats, sheep and cattle.
c. Ladino: 3-4 pounds per acre provides for close grazing and tolerances a slightly lower pH.
Horse owners who have experienced cases of slobbers should not frost seed clovers. Perennial pasture and hay grasses do not germinate as well as legumes when broadcast. These grasses are better drilled directly into the sod. However, orchardgrass and perennial ryegrass may be frost seeded with some limited success.
Changing pasture composition requires changing pasture management. If you continue to manage the same, you’ll keep getting what you’ve got.
For more information contact Clif Little at the Guernsey or Noble County OSU Extension office at 740- 489-5300 or 740-732-5681.