Forty years ago this month, I made my first visit to USDA’s North Appalachian Experimental Watershed in Coshocton, Ohio. Established in 1935, this 1,047-acre facility had been built with depression-era labor from several government assistance programs.
Sadly, the facility was among 259 USDA offices, labs and ag research facilities across the country scheduled for shutdown last year due to federal budget cuts. While a tremendous amount of crop research was conducted over 77 years, three long-term research projects had a tremendous impact on the acceptance of no-till.
40 Years Of No-Till Corn
Among the ongoing projects was a 40-year continuous no-till corn project focusing on rainfall, runoff and erosion. These plots were located on fairly steep, erodible land with an average rainfall of 37.6 inches per year.
Over the years, water runoff averaged only 0.17 inches per acre annually. Yearly soil erosion averaged less than 5 pounds per acre.
In 1997, a trial was conducted to compare the impact of a heavy rain on the 40-year no-till corn site. This was compared to corn grown after 1 year of intensive tillage and corn grown on land that had seen 13 years of continuous tillage.
In May of 1997, 2.5 inches of rain was applied in just 1 hour to the plots. Average runoff on the no-till plots was only 0.27 inches of rain, while 0.91 inches of rain ran off the 1-year tillage site and 1.17 inches of rain was lost from the 13-year continuous tillage plot.
No soil loss was recorded from the no-till plots. Yet the 1-year tillage plots lost 2,096 pounds of soil per acre, while the 13-year continuous tillage site lost a whopping 3,203 pounds of soil per acre.
I remember talking in the 1980s with Bill Edwards about his work with no-till, soil erosion and the movement of water, soil, pesticides and nutrients. He also explained how earthworms are nature’s perfect no-till plow.
“Worms enter the soil with minimal disturbance, leaving only a hole smaller than the diameter of a pencil,” he said. “Then they open up channels throughout the underlying topsoil. These channels help loosen the soil, provide plants with paths for their roots, work in additional organic matter, and drain and aerate the soil.”
The 40-year tillage study demonstrated that worm numbers definitely increase with no-till. The result is improved topsoil and the elimination of most surface erosion since rainwater drains through the wormholes rather than washing soil away on the surface.
It was sad to see USDA shut the doors on this important research facility. But some impressive, far-reaching no-till research was done at Coshocton. As a result of the station’s work, earthworms are now recognized as an important indicator of soil tilth or quality.
And as Bill Edwards often said, “The less tillage, the more worms. The more worms, the better no-till works.”