Erin and Matt welcome Ashley Dean to the podcast to talk about her work tracking and trapping insect pests of corn and soybeans in Iowa, and the breaking news that the EPA has banned chlorpyrifos.
Ashley gives us an update on the low populations of soybean aphids, occurrences of spider mites and grasshoppers, and the slow spread of soybean gall midge into the more central part of Iowa. She also shares her work on trapping corn rootworms and the discovery of a red western corn rootworm. We geek-out a bit about that one.
We discuss the recent announcement that the EPA is reducing the tolerances for chlorpyrifos to zero for all foods. This is a bigger deal than the announcement just over a year ago that Corteva would stop producing chlorpyrifos. Ashley Dean wrote an article about that decision: https://crops.extension.iastate.edu/cropnews/2020/02/corteva%E2%84%A2-en...
We discuss how the removal of chlorpyrifos will reduce the number of insecticides with different modes of action that corn and soybean farmers can use. For details about modes of action, visit this website: https://irac-online.org/modes-of-action/.
There are insecticides that can replace chlorpryifos, but they are more expensive. For soybean aphids, there are also aphid-resistant varieties. Ashley wrote an article about the economic factors related to pest management and soybean production. She developed partial budgets for this article that goes into great detail about the costs of different approaches for managing the soybean aphid: https://onlinelibrary.wiley.com/doi/full/10.1002/ps.6093