“Fertilizer nutrients are less available when the soil pH is low. If you can only afford lime or fertilizer but not both, apply the lime. Phosphorus and potassium will build up in all our soils. If the soil tests ‘High’ in one of these, then research has shown that applying more as fertilizer is a waste of money.”

The single most beneficial technique for lowering N fertilizer costs is to grow forage legumes, he says.  Some legumes are grown in a pure stand, such as alfalfa or sericea lespedeza, but many species of clovers work best in a mixture with forage grasses.

“In addition to providing biological N, legumes offer other potentially important advantages. In some cases a legume/grass mixture may produce more dry matter per acre than grass alone, particularly as compared to grass receiving little or no N fertilizer. The distribution of forage growth in pastures may also be more favorable, thus helping reduce the need for stored feed. However, the single most valuable advantage forage legumes offer is better forage quality on average than grasses, which usually sharply increase animal gains and may enhance livestock reproductive rates,” he says.

Producers also may use broiler litter or other organic materials, says Mitchell. “Alabama produces more total nutrients annually in broiler wastes than are in all the fertilizers sold in the state, and many producers are taking advantage of this relatively abundant source of organic fertilizer. On the average, a ton of fresh broiler litter will contain at least 60-60-40 pounds N-P2O5-K2O. In other words, it is at least a 3-3-2 grade fertilizer.”

In addition, says Mitchell, there are other municipal, industrial, and agricultural organic wastes that may be available to producers.

“The feasibility of using organic waste materials depends on two factors. First, is the value of the nutrients in the material high enough to justify the cost of obtaining and applying it? To answer this question requires knowing the level of nutrients in the material as well as how much will actually become available to plants.

“The second factor is whether the material contains any pathogens, heavy metals, or other undesirable components that could be harmful to animals, humans, or to the soil.”

Producers also can be more efficient in pasture fertilization through practicing better grazing management, says Mitchell. “Research has shown that in many poorly managed continuous grazing situations, less than half the forage produced in a pasture ends up being consumed by livestock. On the other hand, with controlled grazing management, the percent of utilization of the forage produced may be 20 percent to 30 percent higher. This is the same result that would occur if 20 percent to 30 percent more fertilizer was applied.

There is no single answer to the problem of higher fertilizer costs, says Mitchell.

“Different livestock producers will need to take different approaches based upon their location, resources available, and type of operation. In fact, a given producer may need to take different approaches at different times or in different fields including using soil testing, legumes, organic wastes, alternative sources of fertilizer N such as urea, timing of fertilizer application, and improved grazing management.

phollis@farmpress.com