Lawn treatment in the form of pesticides and inorganic fertilizers poses a substantial threat to the environment. Homeowners in the United States use approximately three times more pesticides per acre than the average farmer, adding up to some 136 million pounds (61.7 kg)annually. Home lawns occupy more acreage in the United States than any agricultural crop, and a majority of the wildlife pesticide poisonings tracked by the Environmental Protection Agency (EPA) annually are attributed to chemicals used in lawn care. The use of grass fertilizer is also problematic when it runs off into nearby waterways. Lawn grass in almost all climates in the United States requires watering in the summer, accounting for some 40 to 60 percent of the average homeowner's water use annually. Much of the water sprinkled on lawns is lost as runoff. When this runoff carries fertilizer, it can cause excess growth of algae in downstream...