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Drought, Pests Impact Soybeans
MISSISSIPPI STATE -- As if the drought isn't bad enough, Mississippi soybean farmers are now facing losses to several pests.
Pat Harris, entomology specialist with Mississippi State University's Extension Service in Decatur, said soybean fields have their normal populations of worms and stink bugs building up this fall in addition to the drought stress.
"Soybean plants are having to tolerate both drought and insect stresses this year. Late-planted beans are always more at risk for insect pressure," Harris said. "Pests such as soybean loopers and stink bugs are just adding to an already-bad situation."
Harris said if rains don't arrive soon, the soybean season will be over.
"Plants that are far enough along may not need treatments for worms, which feed on the foliage," he said. "Pod feeders such as stink bugs and podworms are more likely to need pesticide treatments, but all growers need to look at the economic threshold recommendations first."
Growers can consult local Extension agricultural agents for the population numbers researchers believe will trigger the need for pesticide applications.
"It is hard to look at a field with a very low yield potential and consider putting more money into that crop," Harris said. "Still, you don't want the worms to damage a crop above the 20 percent threshold level. If you wait until they reach that level, some chemicals may not control them soon enough to prevent economic damage."
David Shaw, agronomist at MSU, said later-maturing beans are running out of moisture. Mississippi's soybean crop will struggle to make the U.S. Department of Agriculture's prediction of 27 bushels per acre this year.
Mississippi's producers planted as much as 50 percent of the state's 1.65-million acre soybean crop to the early-maturing Group IV soybean. The early varieties allow beans to develop earlier in the year and be much more likely to receive moisture during the critical pod-filling stage.
"Soybean yields are all over the board right now -- from 50 bushels per acre down to 10," Shaw said. "Basically, anything that isn't irrigated is hurting. Some fields that lucked into a few timely rains may yield in the mid-30s."
Shaw said the yield potential and the extremely low commodity prices have growers less than enthusiastic about this year's soybeans.
MSU agricultural economist Tom Jones said November futures prices are around $4.71 per bushel for soybeans. Elevator (cash) prices are between $4.41 and $4.59. Those prices are similar to last year's market.