Herbicide Use in Corn Benefits Cotton and Peanut Farming

Herbicide Use in Corn: Treated (L) Untreated (R)

Herbicide Use in Corn: Treated (L) Untreated (R)

In southern states, corn is often planted in a three-year rotation with peanuts and cotton. One of the values of having corn in the rotation is that effective herbicides that are used in the corn crop control populations of weed species that would be difficult to control in the peanut and cotton crops. Thus, the control effectiveness of the corn herbicides benefit the succeeding peanut and cotton crops.

“Corn in a Deep South crop rotation remains one of the best weed management tools or decisions a grower can make – when he can make it. A corn crop squeezed into a field at least every three years in a corn-cotton-peanut cycle is most effective.

“There is an inherent value to a good crop rotation that is likely priceless, especially in the long-term weed management of a farm,” says Eric Prostko, weed specialist with the University of Georgia Cooperative Extension.

For corn particularly, its arsenal of herbicides is a welcomed addition to fields, he says, noting that most common field corn herbicide programs farmers use all give similar weed control results.

“But for one big reason, corn is the only major crop we grow where we don’t have to use a PPO (protoporphyrinogen oxidase) herbicide. Atrazine is carrying the load for us with corn” he says.

That herbicide’s economic, broad-spectrum weed control is certainly a plus, but the biggest benefit it brings to fields in the Deep South is its control of pigweed – a problem that isn’t going away.

For south Georgia farmer Philip Grimes, the atrazine-glyphosate one-two punch that his corn rotation provides is essential to his management of herbicide-resistant pigweed that showed up on his farm a couple of years ago.”

Author: Haire, B.
Affiliation: Reporter
Title: Corn in rotation a strong weed management tool
Source: Delta Farm Press. 2014-01-17.

Non-chemical Weed Control Methods Fail to Control Weeds in Organic Peanut Trials

Extensive research has been undertaken in Georgia to determine the effectiveness of non-chemical weed control methods for organic production systems. None of the systems has proven effective, meaning that hundreds of hours of hand weeding are necessary to make these peanut fields viable.

“The inability to sustain a reliable domestic supply of organic peanut is partially due to difficult and costly weed control. … The initial attempt to develop weed management systems using propane flaming and [Organic Materials Research Institute] OMRI herbicides in organic peanut was a weed control failure. Propane flaming and OMRI herbicides did not control annual grasses and perennial nutsedges, and provided only short-term control of dicot weeds.”

“A factor that limits successful in-row weed control using cultivation is inconsistent performance. … The lack of consistency using cultivation as the primary means of weed control in organic peanut appears to be a major unresolved challenge. Even when cultivator implements are properly adjusted and operated in a timely manner, in-row weeds can escape control. …hand weeding cannot be completely replaced by intensive in-row cultivation. … This is also shown by the time and cost of hand weeding to control escapes, particularly the brush-hoe cultivator at VE/1 wk in 2009 needing 116 hours/ha to remove escapes at a cost of $1,021/ha.”

Authors: W.C. Johnson1, M.A. Boudreau2 and J.W. Davis2
Affiliation: 1USDA-ARS, 2University of Georgia
Title: Implements and cultivation frequency to improve in-row weed control in organic peanut production.
Publication: Weed Technology. 2012. 26(2):334-340.

Fungicides Necessary for Southeast Peanut Production

In the U.S., fungicides are used in the field to control ten major diseases of peanuts. For decades, peanut harvesting started when the peanuts in a field were stripped of their leaves by one of these diseases. Peanut yields increased dramatically between 1969 and 1987 following the introduction of effective synthetic chemical fungicides. Fungicides continue to be needed to maintain high peanut yields.

“It’s one of the harsh realities of growing peanuts in the Southeast – you will have disease problems. ‘The same type of weather and climate that helps you grow peanuts so successfully in the Southeastern United States also makes it difficult to control diseases,’ says Bob Kemerait, University of Georgia Extension plant pathologist. Fungicide programs, he adds, constitute the single most expensive input a grower will have in peanut production. ‘It’s not seed, insecticides or herbicides. You spend more in fungicides than perhaps anything else – that’s the bad news. The good news is the tremendous value you receive from controlling diseases. We could not make the desired yields and grades without these programs,’ says Kemerait.”

Author: Paul L. Hollis
Title: Peanut fungicides valuable tools.
Publication: Southeast Farm Press. 2008. Vol. 35(12).

Jimmy Carter Lived the Weed Nightmare

Our 39th President, Jimmy Carter, grew up on a peanut and cotton farm long before herbicides were available to manage weeds. In his autobiography, President Carter recounts the nightmare of trying to control weeds with tractors and hand labor.

“Our part of Georgia receives about fifty inches of rain during an average year, mostly during the spring and early summer… However, depending entirely on draft animals and hand labor, small variations in the rain pattern could be devastating. … The dry ground permitted the mule-drawn cultivating plows and hoes to restrain the ever-encroaching weeds and grass. However, when no plowing was possible because of several successive days of rain, the noxious plants were uncontrollable. Something like the terrible creeping and oozing things in horror movies, Bermuda grass, coffeeweed, cocklebur, Johnsongrass, beggar-lice, and nut grass would emerge from what had been a cleanly cultivated field, and in a few days our entire crop of young peanuts and cotton could be submerged in a sea of weeds. Often, despite the most heroic efforts by the best farmers, parts of the crop would have to be abandoned. Although partially salvaged, the remaining young plants were heavily damaged by the aggressive plowing and hoeing. During these rainy times, Daddy would pace at night, scan the western skies for a break in the clouds, and scour the community, often far from our own farm, to recruit any person willing to hoe or pull up weeds for day wages.”

Author: Jimmy Carter
Publication: An Hour Before Daylight: Memories of a Rural Boyhood. 2001. Simon & Schuster, New York.