by Robert Spencer

Urban Regional Extension Specialist
Alabama Cooperation Extension System

As a result of drought weather conditions for the past three years, pastures for livestock grazing may not be in the best shape. While we did receive more rain this past fall, it was sporadic and made it difficult to decide whether to reseed pastures or wait for more suitable conditions. In addition, fertilizer prices were at an all-time high this past year causing many to forego fertilizing. Also, farmers do not always have every piece of equipment or financial resources they would like and often must adapt and improvise in order to accomplish certain tasks such as reseeding pastures. While this sounds like a serious predicament, let me be the first to say there is hope.

Number one, we know legumes are ideal forages to establish in any pasture. They are preferred grazing by most livestock; and they fix nitrogen into the soil reducing the need for fertilizer. Two, spring is a desirable time to plant legumes such as clover, trefoil, alfalfa, and sericea lespedeza. Three, the later part of winter facilitates an opportunity to add legumes of choice and makes it easier to improve pastures. Frosts of February and March force the ground to freeze and thaw thereby forcing the soil surface to expand and contract which allows any seed lying on the surface to settle into the soil as it opens and closes.

This method is known as Frost-Seeding.
The principle is quite simple but does require good timing. At the web site http://www.uwex.edu/ces/crops/frostsd.htm, author Mike Rankin tells us “Seed is broadcast on the soil in mid-spring, when daytime temperatures are above freezing but nighttime temperatures are below freezing. This daily freezing and thawing, which shrinks and swells the soil, works the seed into the soil. When temperatures become warm enough, the seed can germinate in the soil, and begin the process of establishment.” Remember, the seed must work its way into the soil. Timeliness is critical; seed too early and the seed may die – seed too late and there is no frost to do the work.

This seeding method is considered “low-tech” because all that is needed is some type of seed spreader such as a spin spreader and a way to move it about. It is also very affordable because the only major expense involved is the seed and equipment. A spreader that attaches to a tractor, four-wheeler, or large riding mower can be purchased for only a few hundred dollars; or possibly rented by the day or half day for less than one hundred dollars, making the whole effort relatively affordable and practical for those operating with a limited budget.

Some things to remember:

(1) This practice works best on pastures which have been grazed (or mowed) relatively close to the ground.

(2) It works best with legumes such as clover, sericea lespedeza, and alfalfa; trefoil has its limitations.

(3) Timing is important. Weather conditions must allow freezing and thawing allowing the seed to settle into the soil, followed by warm enough temperatures allowing the seed to germinate.

(4) Manage the newly established legumes by allowing the legumes to become well established prior to grazing; do not allow animals to graze pastures below six inches in height; remove animals as needed to allow pastures to regenerate growth; repeat process as conditions allow.

(5) The new seedling must be able to compete with the plants already in place. Birdsfoot trefoil can be used, but struggles to compete with other vegetation as a seedling which reduces the likelihood that it will be successful.

Based on several sources of information, frost-seeding does not appear to work very well for grasses. Most grass seed does not tolerate cold temperatures. If you are interested in adding a grass to a pasture or hayfield in the late winter/early spring, no-till seeding it may be a more practical option.

Minimizing the need for costly equipment, fertilizer, labor, and fuel suits most farmers. Legumes are ideal because the produce nitrogen, provide quality forages, and fertilize existing forages making for a win-win situation. In most of the country mid-February to mid-March is an ideal time to utilize this method of pasture improvement. Every cost-conscious farmer should take advantage of this opportunity.