The practice of coating soybean seed with neonicotinoid pesticides as a safeguard against insect damage provides “negligible overall benefits to soybean production in most situations,” says an EPA analysis. “Published data indicate that in most cases there is no difference in soybean yield when soybean seed was treated with neonicotinoids versus not receiving any insect control treatment.” The Biological and Economic Analysis Division said the pesticide was bioactive for three to four weeks after planting, “which does not overlap with typical periods of activity for some target pests of concern.”
The analysis said “neonic” seed treatment can cost up to $6 an acre. There are “multiple” insecticides available that can be applied as a spray if insects are a menace, it said. Imidacloprid and thiamethoxam are the most widely used neonicotinoids for seed treatment and are registered for use against soybean aphids, bean leaf beetles, wireworms, seed maggots, cutworms and other pests. From 2008-12, neonic-treated seeds were planted on 30 percent of soybean area, says EPA.
“EPA has confirmed what farmers, beekeepers and scientists have been saying all along: neonicotinoids do more harm than good,” said Pesticide Action Network, which called for restrictions on use of neonics.”Not only do neonics provide little protection against pests, they pose serious threats to bees and other pollinators that support the food system.” Some beekeepers filed suit against EPA last year to curtail use of the chemicals.The varoa mite is blamed by some researchers as the greatest culpriit in population decline.