The only thing standing between some Georgia peanut producers and an exceptional year is one more good rainfall, says John Beasley, University of Georgia Extension peanut specialist.
“It has turned off very dry,” said Beasley in late September. “Many of the peanuts planted in late May are showing drought stress, and we entering the peak of our harvest season.”
Areas like southwest Georgia received good rainfall from Tropical Storm Fay, he says, but there has been little or no moisture since that time. “The dry weather is making maturity determination much more complicated, and some of our soils are more difficult to dig when they’re this dry. One more good rain would really help us out,” he says.
Still, says Beasley, Georgia’s peanut crop generally looks good this year, and the state’s estimated average yield of 3,150 pound per acre appears to be accurate. “There have been a few concerns about lower grades, but we’re seeing good yields overall. And the way the season started, it didn’t look as if there was a chance we’d be where we are today. For the second straight year, it was extremely dry in the spring as our producers were preparing to plant,” he says.
Dry soil conditions caused difficulty in land preparation, and many growers waiting for moisture before they planted, says the agronomist. The majority of the acreage in the Georgia peanut belt did receive adequate rainfall in time to complete planting, although some planting occurred in early to mid June, he adds.
More than 95 percent of the state’s acreage is planted after May 1, says Beasley, to help reduce the risk of tomato spotted wilt virus. “This year, more than 80 percent of the peanut crop was planted May 10 or later, and the later planting means we harvest later than in years past,” he says.
The big surprise this year for Georgia growers was the outbreak of tobacco budworms in the southwest region of the state, with some producers being forced to spray several times for the insect pest, he says.
“This was a unique situation this year,” says Beasley. “I’ve conferred with several entomologists who have experienced going as far back as the late 1950s, and no one can remember tobacco budworms being a significant problem in peanuts. None can remember a year when we had to spray specifically for tobacco budworms. It is related to the corn earworm. In the past, whenever there was an outbreak of corn earworm in peanuts, it was not uncommon for the population to have a small mix of tobacco budworms. But this year, the population of tobacco budworms reached treatable levels early.”
Pyrethroid insecticides, he explains, were not effective in controlling tobacco budworms, so producers had to use more expensive insecticides. “Population levels hit unheard of levels, which made control even more difficult. The bottom line is that many producers had to spray an expensive insecticide multiple times, adding significantly to their cost of production,” says Beasley.
Conditions also were favorable throughout the season for white mold, he says. “Unseasonably high temperatures in mid-June created near-perfect conditions for an early and prolonged epidemic of white mold, and peanut producers have battled the disease throughout the year.”
Pressure from tomato spotted wilt virus has been relatively light in Georgia throughout the 2008 growing season, says Beasley. As for weeds, herbicide-resistant Palmer amaranth pigweed has been a problem in some fields, he says.
“Something we don’t have an answer for is the yellowing of peanuts in some grower fields. It may well be the result of an interaction between micronutrients, but we’re not sure at this point,” he says.
One thing is for certain this year, says Beasley. “For the second consecutive year, this has been a costly crop to produce, especially considering the irrigation needed at the beginning of the growing season and the extra insecticides required for controlling tobacco budworms.”
Late-season disease control
As peanut growers head into the final stretch of the growing season, University of Georgia Extension plant pathologist Bob Kemerait makes the following basic recommendations.
Condition 1: If peanuts are within two weeks of harvest, there is little opportunity for a fungicide application at this late date to have any benefit for further disease control. Growers will not likely see a benefit from applying a fungicide with two weeks of projected harvest unless the field is threatened by a tropical storm that could significantly delay harvest.
Condition 2: If peanuts are within approximately three weeks of harvest and disease control (leaf spot and soilborne disease) is excellent, then a grower likely does not need to apply additional fungicide, unless a tropical storm threatens extended delay in harvest.
Condition 3: If peanuts are three or more weeks away from harvest and diseases are still a problem in the field, then a grower should consider continuation of leaf spot and, in worst cases, soilborne disease control with fungicides.
Condition 4: The crop is approaching harvest, but not there yet, and diseases are severe in the field. This is a question growers often ask me, “Should I dig early?” If the disease is tomato spotted wilt virus, the grower is most likely to benefit by allowing the crop to reach maturity before digging. For leaf spot and white mold, it is best to let the crop reach maturity if possible, but this is not always possible. Where these diseases are severe in the field, there may be situations where the grower must consider sacrificing some grade for increased yield. Poor control of leaf spot and white mold in the season can result in increasing losses as pegs break and pods are lost at digging.