Leaving residue on the surface to keep the soil from getting so hot that it seriously impacts plant growth is among the benefits of no-tilling. Along these lines, there’s some interesting research being done at Montana State University that demonstrates how cooler soils not only lead to higher yields, but also reduce the need for fallowing fields to conserve moisture and favorably impact climate change.
“There’s a large region in the Dakotas, extending well into western Canada, that has actually been cooling off in the summer, which bucks the global warming trend,” says Pat Stoy, a Montana State researcher. “Very few people have studied the mechanisms that underlie this, and that’s partly because it’s so difficult to model cloud formation and convective precipitation.”
To get an idea of how important soil temperature is for plant growth, check out the No-Till-Age chart shown at left. Collected 60 years ago at Keerville, Texas, this data shows the impact of different soil temperatures on both underground creatures and plant growth. It helps explain why considerably cooler soil temperatures under no-till residue or cover crops can out-perform bare soils.
It’s a “win-win” situation for farmers, thanks to the growing use of no-till that has led to a decrease in yield-limiting summertime temperatures and a favorable impact on climate change.
Much of Stoy’s research focuses on the benefits of no-tilling every year rather than fallowing fields every other year, a longtime tradition in the Northern Great Plains due to limited moisture…