For Late Plantings, Tropical Corn

Everybody likes variety in food—even cows. And who doesn't love Mexican cuisine?

Tropical corn from Mexico and Central America looks pretty much like its temperate relatives. It won't replace U.S.-bred lines, but it could be a crop that growers choose in addition to forage sorghum.

Farmers usually plant sorghum when it gets too wet or too late in the season to plant temperate corn. So tropical corn could be a good alternative, because it grows well in heat and resists pests.

And when it comes to silage, a fermented wet winter feed, cows seem to prefer tropical corn over sorghum. ARS researchers found dairy cows ate more of the tropical corn silage—so much more, their milk production increased by 10 to 20 percent.

"We also tested tropical corn's nutritional value on 24 steers," says ARS plant physiologist Joseph C. Burns. "Tropical corn may have had a slightly lower digestibility than forage-type sorghum, but the steers seemed to like it better and ate more of it, so it evened out."

Tropical corn actually yields about 87 percent more dry matter than sorghum, making each acre more productive. It can also help control erosion.

Tropical corn's season is: Plant in June, harvest in October. It works best in the southern United States, which approximates its native climate.

Farmers would make and store the tropical corn silage in October. In the corn stubble, they'd plant winter wheat or barley. Alternating tropical corn and the winter crop would protect the ground from erosion and give cows two quality feeds.

Burns is in the ARS Plant Science Research Unit at Raleigh, North Carolina. The test herds were provided by North Carolina State University.

ARS scientists are currently working with a university economist to see if following this practice could also mean extra money for farmers.

"There are about 60,000 acres in tropical corn right now," says Burns. "If it helps improve profits, it might become an even more attractive alternative to sorghum."—By Jill Lee, formerly with ARS.

Joseph C. Burns is in the USDA-ARS Plant Science Research Unit, Room 1119, Williams Hall, North Carolina State University, Raleigh, NC 27695-7620; phone (919) 515-7599, fax (919) 515-7959.

"For Late Plantings, Tropical Corn" was published in the November 1999 issue of Agricultural Research magazine.