Farmers in the valley are seeing levels of disease in their crops that may justify the use of pesticides. Robert Rhoten is the manager and crop advisor for the Intermountain Farmers Association (IFA) in Lewiston.
“They’ve been seeing stripe rust in their cereal grains,” Rhoten said. “They’ve also been seeing cereal leaf beetle. But, then also in the alfalfa they’ve been seeing kind of layer flushes of pests. Whether they be the alfalfa weevil or aphids, they’re starting to cause farmers problems getting up to the threshold levels that are justifying using pesticides to control them.”
Most damage from <a href=”http://extension.usu.edu/files/publications/factsheet/aphids-alfalfa09.pdf” target=”_blank”>aphids</a> is caused between June and August when it is hottest. Rhoten said they first use integrated pest management to keep the insect counts low.
“Sometimes natural predators out in the fields will help lower those pest numbers,” Rhoten said. “But, now we’re starting to see populations increasing that we didn’t see earlier in the spring that’s justifying going out there and controlling those insects. “
Rhoten said rust in alfalfa yields can take a third of their crops depending on the growth cycle of the plant and warns farmers growing corn to watch for spider mites.
He said spider mites thrive in the dry, hot weather but that the corn is low enough that they can get their ground rigs through the crops to treat them. If the corn gets too tall the farmers will then have the increased cost of using airplanes.