A graph, or two, is sometimes worth more than 10,000 words. This chart, sent to me by monarch researcher Chip Taylor, shows the rise in Roundup ready corn and soybeans along side the decline in monarchs counted on their winter grounds near Mexico City. He was responding to a story published Saturday about a new study that showed an 81 percent decline in the reproduction of monarchs since the advent of herbicide resistant corn and soybeans. Turns out they work pretty well -- milkweed has virtually disappeared from agricultural fields in the Midwest, the researchers said.
The green line is monarchs -- the red is the percent of farms planted with herbicide tolerant seeds.
Some researchers say they are not entirely convinced because the latest study, by scientists at the University of Minnesota and Iowa State University, used a lot of extrapolation in their analysis. But Taylor, who is the scientific director of Monarch Watch, a conservation group, and a professor at the University of Kansas, says that the relationship is unequivocal.
