When no-till wheat production first began in far western Kentucky about 20 years ago, University of Kentucky College of Agriculture scientists began studying the production method.

After many years of work in small plots, today the research has moved to large-scale on-farm testing. The research has explored not only how this production affects the wheat yields, but also the yields of subsequent corn or soybean crops.

The early research, conducted by Lloyd Murdock, UK Extension soils specialist, and James Herbek, UK Extension grains specialist, showed wheat had a statistical yield advantage when some form of tillage was used compared to no tillage in three out of eight years data. In the five other years there was no statistical difference. With soybeans six out of seven years there was no difference between no-till soybean yields following no-till wheat.

However, in six years of data two-thirds of the time corn yields in a continuous no-till rotation of wheat, soybeans and corn, were statistically and agronomically significant, said John Grove, UK agronomist.

While some crops such as wheat tend to prefer tillage, especially during a low quality season, corn on the other hand seems to respond favorably following no-till wheat regardless of the season, he noted.

“Corn just likes being behind no-till wheat,” he said.

A look at the soil structure in the small plots showed improvements in water holding capability that can be especially important in some growing seasons, Grove said.

A summary of the small-scale plot research was given to attendees of the annual UK wheat conference as a precursor to Grove’s discussion of large on-farm research that is under way.

The larger research project is being conducted “to see if no-till wheat production enhances yield in corn and soybeans in rotation on Kentucky farms, and we wanted to try to determine if we could relate that to some measurable soil characteristics and explain the variation across a number of landscapes,” Grove said.

So far, six fields are being studied with three beginning in 2000 and three in 2001. Each field is divided into tilled and no-till treatments. In most of these fields there are a number of landscape positions, such as summit, shoulders and back, foot and toe slopes. Additionally, soil characteristics are noted.

Yields are being measured using a yield monitor when the crop is machine harvested. Results in 2001 and 2002 show continuous no-till has yet to benefit corn and soybean yields, but the soil physical properties do suggest that no tillage has begun to positively impact available water holding capacity regardless of landscape position.

“We are just getting started,” Grove said.