In general, legumes work better for frost seeding as compared to grasses. Clovers are most commonly used in partial renovation situations to improve grass pastures or hayfields. Broadcast rates for frost seeding of clover is 6 to 8 lbs. /acre for red clover, 2-3 lbs. /acre for white clover and 2-4 lbs. /acre for alsike clover.
I have been asked the question about renovating an alfalfa stand. Due to an autotoxicity condition that involves the release of a chemical from the roots and plant parts of established alfalfa plants, new alfalfa seedlings do not have a good survival rate, so it is not economically viable to thicken up an old alfalfa stand with more alfalfa seed. It is possible however to convert an alfalfa stand to an alfalfa grass stand by no-tilling a grass into the older alfalfa stand. Good candidates for this type of renovation include orchardgrass and festulolium grass. Festulolium is a grass species resulting from the cross of a meadow fescue with an annual or perennial ryegrass or a tall fescue with an annual or perennial ryegrass. The festulolium combines some of the desirable forage quality and quick establishment of a ryegrass with some of the hardiness traits of a fescue grass.
A final important point regarding pasture or hayfield renovation is soil fertility. To allow that new forage seeding to have a chance to thrive and be productive the soil should have the proper soil pH and nutrient level. Critical or minimum levels include a pH of at least 6.3 for grasses, 6.5 for clovers and 6.8 for alfalfa. Soil phosphorus should be at 25 parts per million (ppm) or 50 lbs. /acre and soil potassium should generally be around 120 to 125 ppm or 240 to 250 lbs. /acre. For more information about pasture or hayfield renovation contact County Extension office, or review the recent "Pastures for Profit" Grazing School presentations you'll find under this link.
-Rory Lewandowski, Ohio State University Extension Educator, Wayne County