Read the magazine story to find out more.

Making Prize-Winning Yields More Routine

When you’re a scientist trying to help farmers get the highest possible yields, who better to turn to than national yield contest winners?

It was on just such a farmer’s field that Agricultural Research Service agronomist Richard L. Cooper discovered his first yield barrier: soybean plants getting so tall they fell over and yielded poorly. That was the prelude to his almost quarter-century-long maximum yield experiment with soybeans.

Cooper, in Wooster, Ohio, removes every possible factor that limits yields--like lack of water or fertilizer--to find the true potential of modern varieties. That, and the long-term nature of his experiment, enabled him to recently discover another previously unknown barrier: a delay in soybean flowering caused by typically cool spring weather. Cooper is based at the ARS Corn and Soybean Research Unit.

He found that warm spring weather triggers earlier flowering--and higher yields. Until breeders develop earlier flowering varieties based on his findings, Cooper recommends farmers plant soybeans up to two weeks earlier than usual.

Cooper has developed a high-yield system for soybeans--70 to 100 bushels per acre--that combines early planting with ARS-developed semidwarf soybean varieties planted densely in narrow rows. Corn used in rotation with soybeans in his research has produced 200-plus bushels an acre.

Cooper has found an unusual source of “free” irrigation water for his system: excess rainwater from underground plastic drainage pipes, collected in the wet spring. Norman R. Fausey, an ARS soil scientist at Ohio State University in Columbus, recommended the irrigation system and is working with Cooper to integrate it into the maximum yield system--a first.

He and Cooper have built wetlands and reservoirs to store the drainage water, which would normally empty into streams and possibly pollute them with farm chemicals. Preliminary data indicate that the drained water becomes significantly cleaner after being filtered through wetlands or reservoirs. Then, during the dry, hot days of summer, farmers can irrigate through the drainage pipes.

A more detailed story appears in the June issue of Agricultural Research, ARS’ monthly publication.

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