During the summer, green slime, also known as blue-green algae, disrupted the water supply for Toledo. Nutrient runoff from farms, especially phosphorus fertilizer, gets part of the blame for feeding the algae blooms. PRI’s “The World” program says tactics to reduce runoff “are relatively simple, like planting cover crops to hold the soil. Others are a bit more complex.” It visited a farm in Kingsville, Ontario, on the north shore of Lake Erie, where farmer Henry Denotter uses precision equipment including GPS systems on tractors, sprayers and combines to match fertilizer needs with crop productivity. An air seeder injects fertilizer into the soil at rates that vary with a “prescription map” for each field.
“This kind of technology costs a lot of money, a lot more than many farmers can afford,” says PRI. The algae blooms of this summer are creating urgency to act. “The joint US-Canadian agency that oversees water quality in the Great Lakes will release tougher phosphorus targets for Lake Erie next year,” is says. The goal could be a 40 percent reduction in phosphorus, says the Milwaukee Journal Sentinel.