By Sara QuamProponents of expanding the Luverne Municipal Airport runway say it would improve the local economy in many ways.One of those ways is by helping a huge existing business — agriculture.Airport Board Chairman and Luverne City Council member Pat Baustian said that by having the airport, farmers can spray for soybean aphids and get better yields.Fields sprayed for aphids yielded an average of 12 bushels more per acre than fields that aren’t sprayed, according to Matt Mostad, a crop advisor with J.R. Simplot Co."Some had 17 bushels difference," Mostad said.Baustian said the improved yields couldn’t happen without the airport.Mostad said, "There’s a definite benefit to spraying by air."Aphids attach themselves to the underside of the plant leaves, and the air spraying stirs the leaves and hits the plant better.It costs about $7 per acre to spray for the aphids and the profit improvement is much greater, if beans are $5.70 per bushel, for example.Simplot sold chemical to spray 29,000 acres in Pipestone and Rock County.This summer about 34,000 acres of soybean crop was sprayed for aphids in Rock County.Advantage of longer airport runwaysThe city of Luverne is in the midst of a runway expansion effort to increase the runway from 2,500 feet to 4,200 feet long.A longer runway would mean bigger loads of insecticide could be flown, in some cases, making the fight against aphids more efficient.Planes can generally spray about 160 acres at a time.Mostad said, "There are a few planes that would definitely benefit from a longer runway."Baustian said, "People used to think of the airport as some kind of boys’ club, but it’s a very important part of our infrastructure."The next step in getting a longer runway is an environmental assessment, which the city might be able to get funded through the state. City Administrator John Call, Mayor Andy Steensma and Airport Board member Steve Perkins are going with a project engineer to a meeting with MnDOT to try to secure funding next week. With that, the project would move forward and possibly be done in a couple years, rather than in the next seven or so.The bug that bugs soybean plantsMostad said aphids were handled better this year than ever before."It’s all timing, and we don’t have that long of time to get to them," Mostad said.The aphid battle is a fairly new one to agronomists and farmers.The soybean aphid first arrived in the United States in 2000. They are difficult to see because of their small size, but are comparable to the head of a pin. They are lime green in color.They are harmful to soybean crops because they suck the sap out of soybean leaves, limiting plant growth and creating yield loss. The University of Minnesota Extension Service says that the economic treatment threshold for soybean aphid is 250 aphids/plant on at least 80 percent of the plants. Soybean aphid populations at or above this level justify an insecticide application since treatment costs should be at least offset by prevented yield loss. Populations below this threshold should be monitored every three to four days. Under favorable conditions (temperatures in the low 80s and drier conditions), soybean aphid populations can double in about two to three days. The asexual insect is actually born pregnant.The economic treatment threshold has a built-in safety measure of about seven days in order to give growers time enough to make an application before yield loss occurs, which is when soybean aphid populations reach about 1,000 aphids/plant.
