Organic farming may produce higher yields of certain crops during periods of drought, according to a long-term study led by the Rodale Institute.

Data comes from a 40-year report of the institute’s Farming Systems Trial based in Kutztown, Pa., the longest running side-by-side comparison of organic versus conventional grain production systems in North America.

The report shows that, while organic and conventional farming methods typically yield the same, some organic grains performed better in drought years.

Overall, organic corn yields were 31% higher than conventionally grown corn. Organic oats also had nearly twice the output over conventional oats, research discovered, though wheat yields were not significantly different between conventional and organic from 2008 to 2020.

The findings could be meaningful for growers in other parts of the country, including the drought-stricken West, said Reza Afshar, chief scientist for the Rodale Institute.

“We believe a lot of these benefits will be seen in other locations,” Afshar said.

Founded in 1947, the Rodale Institute is a nonprofit organization that supports research, education and outreach for organic agriculture.

The Farming Systems Trial was established in 1981 to provide scientific evidence that organic farming practices can compete with conventional practices. It combines 72 research plots on 12 acres, comparing three production systems — conventional, organic manure and organic legume.

Each system was further subdivided in 2008 to compare full tillage to reduced tillage practices.

Higher yields in organic systems during drought can be traced back to soil health, Afshar said.

Their research has determined organic plots retain 50% more soil carbon, which in turn helps the ground hold more moisture for longer periods of time.

“We see higher carbon sequestration in the soil that can lead to higher organic carbon,” Afshar said. “That is the backbone of soil health.”

Using conventional fertilizers and herbicides, on the other hand, does not spur as much soil microbial activity, Afshar said. Using cover crops in organic systems also promotes soil health by minimizing wind and water erosion.

“Organic systems are much more diverse,” Afshar said. “You have a much higher biodiversity in organic systems.”

Transitioning to organic farming, however, does not come without risk. It takes three to five years to convert to organic, depending on the system and commodity.

During that time, farmers pay more for inputs and learn new farming methods while not receiving any of the price premiums for organic products.

Afshar acknowledged that information from the Farming Systems Trial may not be directly applicable to crops in other regions, though he said the principles of soil health are the same.

The institute has opened several regional organic resource centers around the country, including one in Ventura, Calif. A new center in Washington has also opened, about 20 minutes from Seattle, and will focus on the challenges of growing organic specialty crops unique to the Northwest, such as blueberries.

“Improving soil organic carbon and soil health is one big step toward making systems more resilient to drought stress and water scarcity,” he said.