University of Georgia researchers studying organic peanut production and researchers with the USDA’s Agricultural Research Service have found ways to reduce the amount of chemicals used in traditional peanut farming operations.

Supported by a series of Southern Sustainable Agriculture Research & Education (SARE) grants, the critical breakthrough in the overall research effort was a weed control strategy based on intensive cultivation. This includes using the right equipment in conjunction with cultural practices that enhance peanut competition with weeds.

The production system — validated on certified organic fields — works, said Carroll Johnson, a USDA-ARS research agronomist with the UGA campus in Tifton.

“We went through several years of consistent failure before we started seeing regular successes in weed control techniques,” Johnson said. “Since then, we’ve had a pretty good idea of how to manage weeds in organic peanuts.

“At our research site in Tifton, we were heavily infested with the major weeds that plague peanut growers: crabgrass, Texas millet, crowfoot grass and small-flower morningglory, just to name a few. We gave our organic weed control systems a real-world test.”

A key to successful weed control is finding the right cultivation implement, and that implement turned out to be the tine cultivator, Johnson said.

“The saying goes that if you see a weed, then it’s too late,” he said. “When properly operated, the tine weeder eliminates the weed before it even has a chance to emerge from the soil.”

The magic behind the tine cultivator is the flexible tines that scratch just beneath the soil, bringing the weed seedlings to the top where they dry up and die on the soil surface.

“I usually start using the tine cultivator right before the peanut crop emerges and then repeat at weekly intervals for six weeks,” Johnson said.

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Another interesting development during the research was the awareness that peanuts are much more tolerant than originally thought to the intensive cultivation needed to control weeds.

“We basically took the peanut production handbook and put it through the shredder,” Johnson said. “We were doing things to peanuts with intensive cultivation that had not been done before and getting away with it, and that is due to the superior peanut varieties now available to growers.

“There are some resilient peanut varieties out there that have enough disease resistance and tolerance to the physical abuse of intense cultivation that makes it possible for us to produce organic peanuts in the first place. That was an important discovery right there.”

The team was concerned that leaf funguses and soil-borne diseases would be limiting factors due to the absence of fungicides, but that has not been the case, Johnson said.

“We have outstanding peanut varieties that give us disease tolerance or even resistance, along with strong yield potential,” he said.