Reducing late-season nitrogen can reduce costs without affecting yield

Growers may be able to cut back on late-season nitrogen application in sweet corn, according to Oregon State University Extension agronomist Don Horneck.

In a presentation at the Hermiston Agricultural Research and Extension Center's sweet corn field day Aug. 31, Horneck said corn stops taking up nitrogen late in the season.

"Be extra careful about putting on late-season nitrogen," Horneck told growers, "because there's not much need for it."

With some variance between varieties, nitrogen uptake ceases when corn plants reach 50 percent dry matter, Horneck said.

Sweet corn typically needs about 225 pounds of nitrogen an acre during a season, Horneck said. Given that corn does not take up nitrogen efficiently, growers may need to apply upwards of 300 pounds an acre to provide sufficient fertility.

This information and more is available in the newly updated Western Oregon Sweet Corn Fertilizer Guide, Horneck said.

The guide will be available no later than Jan. 1, 2011, on the OSU Extension publications website at http://extension.oregonstate.edu/catalog

--Mitch Lies