Researchers report good and bad news from their work on pigeon pea, a very drought-tolerant, tropical annual legume.

The good news: Pigeon pea has the potential to fill the gap in late summer and early fall when graziers run short of forage. In USDA-ARS studies, its yields ranged from 1,000 lbs of dry matter/acre in July to 11,300 lbs in early October.

The bad news: Pigeon pea seed that's adapted to the U.S. is hard to find.

“The University of Georgia has produced over 14 tons of pigeon pea seed from four varieties developed here,” says Sharad Phatak, a horticulturist at the university. “However, these varieties, which are adapted to the southeastern U.S., have not been officially released. So seed is not available to the general public.”

Pigeon pea seed can be imported, but those varieties may not do well in the U.S., says Phatak.

He's collaborating with University of Georgia animal scientists and area farmers to learn more about the legume.

“Cattle will graze pigeon pea when it's 1' to 18" tall,” he reports. “After that, they'll leave it alone for awhile. Then they'll come back and graze again after pods are formed.”

At the USDA-ARS Grazinglands Research Laboratory in El Reno, OK, agronomist Srinivas Rao and his colleagues have studied the crop extensively.

“High-quality forage is often unavailable for Great Plains cattle producers from late July through late November because the quality and quantity of warm-season grasses declines and winter wheat forage isn't ready yet,” says Rao. “Pigeon pea could fill that void.”

The Oklahoma researchers evaluated seasonal production patterns, yield and quality of three varieties obtained from the International Crops Research Institute for the Semi-Arid Tropics in India. Those varieties boast medium to long growing seasons and flower in 180 to 220 days.

“Those longer-duration varieties could be grazed or made into silage or hay, while shorter-duration varieties that flower in 120 days could work for both forage and seed production,” says Rao.

The researchers agree that pigeon pea seed could be fed to livestock as a replacement for other protein sources, such as soybean meal. The seed has 22-25% crude protein and forage can reach 20% protein.