A perennial legume, popular in hay production for its long-term persistence and high nutritional value, is being explored in Florida as a nitrogen-fixing grazing crop in beef cattle pasture systems.

Kim Cline Mullenix, a graduate assistant of agronomy and forage management at the University of Florida, has received a two-year $9,978 Southern Sustainable Agriculture Research and Education Graduate Student Grant to study strategies to establish rhizoma peanut (Arachis glabrata) in bahiagrass pastures.

The goal is to find low-input nitrogen-fixing alternatives to nitrogen fertilizers in grass pastures, while promoting sustainable grazing methods, said Mullenix.

“We’ve been finding that beef cattle producers add very little nitrogen fertilizer to their pastures, or they don’t add any at all because of the increasing costs. That has an impact on not only the quantity and persistence of the forage, but also the performance of the animal and number of animals that can be supported per unit land area, resulting in monetary losses to the farmer,” said Mullenix.

“This research is part of a larger effort of providing technologies that lead to sustainable grass-rhizoma peanut pastures with no requirement for nitrogen fertilizer.”

Producers, however, face a major challenge in using rhizoma peanut in grazing systems: establishment costs are high.

“Rhizoma peanut is propagated vegetatively, not by seed. It costs about $550 an acre to establish the perennial, and it takes two years to get an adequate stand,” said Mullenix. “As a result, rhizoma peanut is usually reserved for production systems that have high economic returns, namely hay production for horses.”

One way to address this issue may be to use strip-planting, or tilling and planting small areas of rhizoma peanut in grass pastures.

Mullenix will use strip-planting to establish small areas of rhizoma peanut in bahiagrass pastures with the idea that the peanut may spread into the grass component over time. This approach may help decrease initial input costs so that the crop can be used in more low-input production systems and increase the nutritive value of the overall stand