Pigeonpea May Fill Seasonal Forage Gap

By Luis Pons
August 8, 2002

Livestock producers across the Great Plains could one day have the benefits of nutritious forages year round, thanks in part to pigeonpea.

Agricultural Research Service scientists, led by agronomist Srinivas C. Rao at the Grazinglands Research Laboratory in El Reno, Okla., found that the legume has the potential to fill a gap in forage availability that affects livestock farms between late summer and fall.

Pigeonpea, or Cajanus cajan, is a summer legume with excellent drought tolerance. Used extensively in Asia for human food and livestock feed, it ranks sixth in the world in dryland legume production.

Research showed that pigeonpea yields and nutritive values during the summer equaled those of other forage crops reported for the region.

Potential benefits to the farmer would include lowered costs of livestock production and improvements in soil fertility, thanks to the ability of this productive legume to transform nitrogen from the atmosphere into a form plants can use to fuel their growth--a process called "nitrogen fixation." Pigeonpea could also reduce vulnerability of soils to erosion by wind and water during the summer fallow period between winter wheat crops.

A goal of grazing research programs is to provide high-quality forage year round to reduce the costs associated with harvesting and storing forage and of purchasing concentrate feeds for use when green forage can't be grown.

Since no single crop has the potential to provide year-round forage, identifying new forage species that can be grown when others aren't productive makes this pigeonpea alternative important.

The primary forage resources for livestock production in the Great Plains are winter wheat during early winter and spring, and perennial grasses during spring and summer. But high-quality forage is often scarce from late July through late November, because the quality and quantity of grasses decline and winter wheat forage is not yet available.

Read more about this research in the August issue of Agricultural Research magazine.

ARS is the U.S. Department of Agriculture's chief scientific research agency.