Step 1. Have the soil tested and apply the needed lime and fertilizer. Legumes need a higher soil lime and fertility level than grasses. DO NOT use nitrogen at seeding. Adding nitrogen stimulates grasses, which increases competition with the legumes. Don't ever use DAP (18-46-0) or Triple 19 or Triple 10 as these fertilizers have enough nitrogen to make the grass grow enough to crowd out the clover. Your fertilizer should usually be put on after the first grazing or hay harvest.
Step 2. Reduce the vegetative cover on the soil. This is best done by heavy grazing in late fall and early winter. Removing the excess grass cover will make it easier to get the legume seed in contact with the soil. If that clover seed can't get down to the soil, it doesn't have a chance of survival.
Step 3. Select the legumes to be used. This will depend on the soil and the planned use of the forage. For hay, alfalfa or red clover is usually best. For both hay and grazing, a combination of red clover and ladino clover works well. Ladino, red clover and/or annual lespedeza work well in pastures. Alfalfa works well for pasture if you use the grazing types.
Step 4. Use the right kind and amount of seed. Select varieties that perform well in the U.K. Extension Testing Program. If legume seed is non pre-inoculated, be sure to use the right kind of high quality inoculant mixed with the seed just before planting. (Seeding rates- Alfalfa 20 lbs./acre; Red Clover 8-10 lbs./acre and 1-2 lbs. White Clover).
Step 5. Plant the seed so that it makes good contact with the soil. There are several ways to do this. One method is to use a disk, field cultivator or field tiller. Disturb 40 to 60 percent of the sod for planting clovers. For alfalfa seeding, almost all of the sod should be torn up. Tillage helps control the grass growth and exposes the soil so the legumes have a better chance to germinate and grow. Broadcast the seed and pack the soil with a corrugated roller. Another method to seed clover and alfalfa is to use a no-till renovation seeder. These do a good job of placing the seed in the soil, but they don't reduce the competition from the grass. With no-till you need to use a herbicide to hold the grass back. Herbicides must be used to kill or suppress some of the grass and help control competition.
For clover but not alfalfa, a simple, and effective method is to broadcast the clover seed on the soil surface in late winter (Feb. 5 to March 5) on closely grazed (sandpapered) pastures. As the soil freezes and thaws, the seeds become covered. A simple rule to follow here is if the grass stubble is ankle high it's too tall for overseeding so in that situation you need disk or use no-till procedures.
Step 6. Control grass and weed competition. This step is one of the most critical ones. Many attempts at renovation have failed simply because the grass was allowed to grow and reduce the light, nutrients and water available to the young legume plants. The grass must be kept short by grazing or mowing until the new legume plants are three to four inches tall. Stop grazing when the animals begin biting off the young legume leaves. Grazing and mowing should be stopped for four weeks to allow the legumes to become well established. After this, the field should be mowed or grazed on a schedule that will help keep the particular legumes used in good condition. A rotational grazing system helps keep legumes in the stand longer.
For more information on pasture renovation, stop by the Lincoln County Extension Office, 104 Metker Trail, Stanford, 365-2447. Dan Grigson, U.K. Extension Agent for Agriculture.