Posted February 9, 2018
According to the Wisconsin Department of Natural Resources (DNR), fossil evidence suggests blue-green algae have been around for millions of years, with algal blooms dating back to the 12th century. However, the agency notes, “[I]t is possible that the frequency and duration of blooms are increasing in some Wisconsin waters as a result of increased nutrient concentrations.”2 The problem of increasing algal blooms is not unique to Wisconsin — it’s happening all over the U.S., particularly in agricultural areas where the use of phosphorus-based fertilizers is prolific. Phosphorus is a known driver of blue-green algae, as they use it readily for fuel. Researchers have uncovered another, relatively surprising, source of phosphorus that also appears to be driving the toxic algae growth to unprecedented levels — glyphosate, the active ingredient in Roundup herbicide. Read more.