New EPA documents have finally put hard numbers to the use of neonicotinoid insecticides, which have quietly grown to dominate corn and soybean acreage in the U.S. over the past five to six years. Data on the usage of clothianidin (Poncho, from Bayer), thiamethoxam (Cruiser, from Syngenta) and imidacloprid (Gaucho, from Bayer and Valent USA) has been scarce in the past, in part because the EPA does not regulate seed treatments in the same way it does foliar or soil applications of the same chemicals. Now pollinator and aquatic risk assessments on three neonicotinoids released on Jan. 12 revealed what many have long suspected: the chemicals are everywhere.
EPA estimated that 42 million to 61 million acres of corn are treated with clothianidin annually (45% to 65% of all U.S. corn acres), and 24 million to 42 million acres of corn are treated with thiamethoxam (26% to 45% of all U.S. corn acres). That means, in any given year, nearly 100% of U.S. corn acres are likely treated with one of two insecticides.
In soybeans, 13 million to 21 million soybean acres are treated with thiamethoxam (16% to 25% of all U.S. soybean acres), and 2.1 million acres are treated with clothianidin each year (3% of all U.S. soybean acres). The number of imidacloprid-treated soybean acres is likely substantial, although EPA did not report that number. However, the agency did estimate that 880,000 pounds of imidacloprid were applied to soybeans in 2014. For comparison, that is nearly three times the amount of thiamethoxam applied to soybeans each year, which accounted for 13 million to 21 million acres.
These numbers represent a major shift in the traditional understanding of agricultural pesticide usage, where herbicides reigned. In 2014, USDA reported that while 97% of corn acres had herbicides applied to them, insecticides were used on only 13%. Likewise, in 2015, USDA estimated that 96% of soybean acres received herbicides, compared to insecticide applications on just 22%.
The new numbers on neonicotinoid seed treatments confirm that insecticide and herbicide use are not actually so far apart. Insecticides have merely gone underground -- in the form of seed treatments. Heavy dependence and repeated use of certain herbicides, insecticides and genetic traits have led to resistant-pest problems in the past.
Source: DTN Progressive Farmer, January 17, 2017
https://www.dtnpf.com/agriculture/web/ag/news/farm-life/article/2017/01…
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