Want healthier soil? Don’t plow.

Corn crop growing in field (USDA)
A tillage system gaining popularity with farmers leaves 30% of the soil covered with the previous year's crop residue. (USDA)

As farmers adapt to the effects of climate change, they want cost-effective ways to maximize available water and improve soil. More and more farmers are discovering conservation tillage (also known as conservation agriculture).

Instead of disturbing the soil by plowing after a harvest, the farmers leave residue, such as maize stalks or wheat stubble, on a field as they plant the next season’s crop. The practice boosts the soil’s ability to hold moisture, allowing crops to grow better during dry-weather extremes. The method also offers other benefits:

  • Reduces soil erosion by as much as 60%, depending on the tillage method and amount of residue left to shield soil from rain and wind.
  • Adds healthy organic matter to soil.
  • Requires fewer tractor trips across the field, which means less spending on fuel and planting.
  • Reduces air pollution from dust and diesel emissions.
  • Reduces soil compaction, which can interfere with plant growth.

Over time, conservation tillage accompanied by crop rotation and the use of cover crops has been shown to increase harvest yields and enrich soil.

The U.N.’s Food and Agriculture Organization’s recent case study in the Indo-Gangetic Plains found that conservation agriculture reduces water applications by as much as 40%, improving fertilizer efficiency and boosting rice and wheat yields from 5% to 10%.

What’s more, on the eastern plains — where fields typically remain fallow for 80 days after the wheat harvest — a summer mung bean crop planted on zero-tilled soil produces 1.45 tons per hectare, worth $745.

Staff writer Lenore T. Adkins contributed to this article.

This article was originally published May 27, 2016.