Strip-tillers may increase corn yields by precisely planting seed near, but not directly on top of strip-tilled fertilized rows, according to a 3-year research study conducted by Kansas State University.

The best location for planting is determined by how soon corn is planted after fertilizer application and the rate and form of fertilizer used, says Keith Janssen, Kansas State University soil management agronomist.

"Strip-tilled fertilized rows could have air pockets under the row, might be dry or cloddy or could have excessive levels of fertilizer salts or free ammonia," Janssen says.

"On the other hand, planting too far away from the strip-tilled fertilized rows might reduce benefits from residue management including warmer loosened soil and rapid root-to-fertilizer contact."

Janssen conducted a 3-year study in fine-textured soil in eastern Kansas to determine the optimum location for planting corn using strip-till. He discovered that planting seed directly on top of freshly, strip-tilled fertilized rows actually reduced yields, in some cases by up to 8%.

"Overall, the best location for planting on these fine-textured soils was within 3.75 inches of the strip-till fertilized rows and where the seedbed was firm and moist," Janssen says.

"This is most likely to ensure good plant stand establishment and quick contact between corn roots and fertilizer."