Johnson discusses ban of pesticide used to control potato disease for The County article

Steven Johnson, University of Maine Cooperative Extension crops specialist, was interviewed for The County article, “The pesticide Maine potato farmers use to control disease is being banned around the world.” There have been recent national and international changes in the regulation of the fungicide chlorothalonil, so growers may want to start transitioning to using newer chemicals, the article states. Chlorothalonil is the primary fungicide used to control late blight, the quasi-fungal disease that causes rots and led to the Irish potato famine. The chemical also is considered a “likely human carcinogen” by the U.S. Environmental Protection Agency, can leach into groundwater, and is toxic to fish and aquatic species, and possibly to honeybees and native pollinators. Johnson said Maine growers typically use fewer than 12 to 15 applications of chlorothalonil in a season, but future government-mandated reductions may be likely and the current amounts may also limit export opportunities. He’s researching new alternatives to the chemical — they can be just as effective, and used less frequently and in smaller concentrations, but they may be unfamiliar to longtime farmers. Johnson is sharing his knowledge through meetings, field days and in newsletters, according to The County. “I’ve been working on this for the last 10 years,” said Johnson. “We have a lot better and newer chemistries that have better and longer efficacy. Newer fungicides are used at a much lower rate and generally speaking are less toxic to people, aquatic life and non-target organisms.” And these newer chemicals fit well into the strategy of integrated pest management where pesticides are used only in response to an economic threat, Johnson said. “Fungicides don’t increase the yield; they protect the yield. When a yield isn’t threatened, they don’t need to be used for controlling the pathogen. It keeps money in people’s pockets.” The Bangor Daily News published The County article, and the Associated Press cited it in a news brief. Maine Public, Morning Ag Clips, WABI (Channel 5), Portland Press Herald, Fosters.com and Houston Chronicle carried the AP article. News Center Maine carried the BDN story.