The new law, which goes into effect on Jan. 1, 2012, exclude farms, golf courses, and new lawns and homes whose owners can prove through soil tests that their lawns need phosphorus to encourage new root growth.
Many cities and counties in Michigan have already banned the use of phosphorus-containing fertilizers within their jurisdictions. Great Lakes states with similar policies include Minnesota, Wisconsin, New York and Illinois. Phosphorus is a concern because it encourages the growth of algae, which depletes water of oxygen and creates "dead zones" in lakes, rivers and streams.
Because of these bans, many fertilizer makers have removed phosphorous from their products. Manufacturers also have dropped phosphorus from dishwasher detergents after 15 states, including Michigan, imposed bans this year.