This extensive research has resulted in Auburn University recommendations that call for 20 pounds of nitrogen per acre at fall planting on Coastal Plain soils if wheat is grown for grain only.

Limestone Valley soils are less responsive to fall-applied nitrogen.

“If wheat is following a heavily fertilized corn crop, a good peanut or soybean crop, or a drought-damaged crop that could not utilize all of the nitrogen applied, then often no additional fall nitrogen will be needed on wheat for grain.

“If wheat is to be grazed or if more fall growth is desired and is possible, then up to 100 pounds of nitrogen per acre should be applied in the fall,” according to the recommendations.

The remainder of the nitrogen (60 to 100 pounds per acre) should be applied at Feeke’s growth stage 4 or about mid-February in south Alabama.

In north Alabama, nitrogen should be applied between Feeke’s stages 4 through 6, with Feeke’s stage 6 being at about mid-March.

The complement of nitrogen can be applied in split applications if desired and a high yield potential exists (80-plus bushels per acre).

In south Alabama, where spring temperatures rise dramatically, wheat develops rapidly, and nitrogen must be available during this rapid period of green, leafy growth.

“Afterwards, heading and ripening also occur quickly, and there is not enough time for split nitrogen applications.

“In north Alabama, where cooler springs may prevail, wheat develops slower over a longer period of time. This also may be conducive to higher yields if nitrogen is available throughout this period. “Therefore, split nitrogen applications may be desirable for high yielding wheat in north Alabama,” according to recommendations.

Research has found no wheat yield increase to splitting nitrogen fertilizer rates when wheat was planted following cotton.

The main concern with over-application of early spring nitrogen is the potential for lodging and possible freeze damage in northern Alabama.

Looking at the effect of other nutrients on wheat, Balkcom says low phosphorus levels can be detrimental.

“We had 40 percent of the top yield of 52 bushels per acre when phosphorus was deficient. We take a hit with deficient potassium levels, but it’s not as detrimental.”

The easiest way to guard against deficiencies is with soil-testing, he says.

“It’s easy to take a soil test and then fertilize accordingly. Where we had no sulfur and no micronutrients, there was no effect on wheat. The major things we need to be concerned with as far as wheat goes are nitrogen, phosphorus, potassium and pH.”

phollis@farmpress.com