Suffolk, Va., grower John Crumpler says he has known for a long time that extending rotation is a sure way to increase productivity, but adds that is especially true for peanuts — especially if soybeans are in the rotation.
Crumpler worked in the fertilizer business for 12 years, sold tractors for a couple years and bought grain for a couple more. In 2005, he got back into farming full time, and has never looked back.
“We have had some good crop years since I’ve been back in farming, and 2008 was one of our best,” Crumpler says. Peanuts were the shining example of Crumpler’s success. He is the reigning Virginia Peanut Yield Champion, producing 5,686 pounds per acre on 132 acres of peanuts.
Though such ultra-high yields are usually accomplished using irrigation, Crumpler grew his award-winning crop without it.
He and his farming partner, Bobby Rountree, grow about 100-150 acres of peanuts every year, plus corn, wheat and soybeans. While he doesn’t dispute the wisdom of keeping soybeans out of the rotation, Crumpler says beans have not held back peanut yields for him. Most of his peanuts are grown for seed, so he cannot have soybeans in the rotation in those peanuts.
“We extend the rotation a year longer in fields that have been planted to peanuts, and we take special care to monitor and manage disease problems. However, last year some of the best peanuts we grew were behind wheat and soybeans,” Crumpler says.
He adds that peanuts had not been grown on that particular land for eight years. With peanut acreage expected to be down at least 30 percent in 2009, many growers have been reluctant to put soybeans in as a replacement crop because of the added nematode risk, and subsequent disease risk.
Virginia Tech Plant Pathologist Pat Phipps says, “Soybeans and other leguminous crops share many of the common destructive diseases with peanuts and should be avoided. Where soybeans are grown in a peanut rotation, double-crop soybeans with wheat and follow with either cotton, corn, or another grass-type crop.”
Long-time Virginia Crop Consultant Wendell Cooper, who works with Crumpler, says some of the new fungicide products may allow growers in some situations to put soybeans in a peanut rotation without as much risk.
Soybeans in a peanut rotation causes three major problems: Nematodes, CBR (cylindrocladium black rot), and stem rot. Using Vapam reduces the risk of nematodes and CBR in peanuts, which is the same disease as black rot in soybeans. And, Provost reduces the risk of stem rot, Cooper explains.
Using Vapam or metam sodium, is a must for the Virginia grower. “I wouldn’t want to plant a peanut crop without it. The risk factor for me goes up about 1,000 pounds per acre without Vapam,” says Crumpler.
Whether or not growers will have Vapam in their arsenal long-term is a big question, especially for North Carolina and Virginia peanut growers.
Virginia Tech’s Phipps recently testified on behalf of continued use of metam sodium for Virginia growers at a meeting in Washington D.C. He believes growers will likely still be able to use the soil fumigant, but the question is whether restricted use guidelines will make it impractical for them to use it.
If growers can’t use metam sodium, there are alternatives to controlling CBR in peanuts, but not as efficiently as using the popular soil fumigant. Longer rotations and the new fungicide Proline are good tools under moderate disease pressure, he says.
Vapam in peanuts, Cooper says, is like having an extra year in the rotation. Without it, he claims adding a year may or may not make up the difference. Using Temik for nematode control and Proline for CBR control, he contends, would help offset the loss of Vapam.
Proline (prothioconazole) was recently labeled for use on peanuts. In tests across the peanut belt it has shown superior control of leaf spot to other sterol inhibiting fungicides commonly used in peanuts. It has also shown good suppression of CBR, but not for tomato spotted wilt virus.
CBR has been a constant problem for Virginia peanut growers through the good times and bad. Soybeans are not the only suspect in the spread of the disease. For many years, some growers thought birds were the primary reason the disease spread so rapidly across Virginia’s peanut belt.
A study by Virginia Tech Researchers R.B. Hiller and P.F. Scanlon put that rumor to rest recently. A total of 30 bird species were observed using 20 peanut fields in southeast Virginia. Fecal material, soil from feet, and crop contents were taken from six bird species collected in the fields and analyzed for the disease-causing agents in CBR.
Even force-feeding grain containing the disease causing fungi failed to produce significant levels to cause CBR. The obvious conclusion — birds are not the reason for the spread of CBR in Virginia peanut fields.
Stem rot (white mold), caused by the fungi Sclerotium rolfsii ) is another limiting factor in putting soybeans in a peanut rotation. Cooper says the highly efficient fungicides available to growers today can put the brakes on stem rot effectively, if these materials are applied in a timely and efficient manner.
He notes that Crumpler also uses Temik and plants in twin-rows, which is a big advantage in keeping the peanut plants healthy, especially early in the season.
Variety is another key factor in managing disease problems and Crumpler says he is constantly seeking new varieties that will give him a yield and quality boost and helps him manage disease problems.
In his award-winning peanut crop, Crumpler planted about 75 percent of his crop in NCV-11 and the remainder was Champs.
He says he probably will not plant Champs, unless forced to by a contract obligation because they didn’t do any better than NCV-11. Phillips is a likely choice for 2009 to try and find a variety that will beat NCV-11. “Champs were close to being as good, but not any better — I need better yields,” Crumpler says.
Crumpler says he usually sows a cover crop for his peanut land, but he did not do that for the 2008 award-winning crop. He typically uses 20 pounds of nitrogen, 60 pounds of potash with K-mag and 50 pounds per acre of phosphate. He also used a high rate of calcium-containing land plaster, noting that it’s needed for the high yields he grows.
With a lack of peanut contracts and those issued less than $500 per ton, peanut acreage in Southeast Virginia is likely to be reduced significantly. For Virginia grower John Crumpler, the question is not how many peanuts he grows, but how efficiently he grows what he plants.
There are plenty of tools in the shed for peanut growers to use to offset a number of production problems, but the best way to boost yields and quality is still a good, long rotation with other non-disease host crops.
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