Dane County's done it, now statewide restrictions are proposed on phosphorus in fertilizer. A couple of state lawmakers propose a statewide ban on sale and use fertilizers containing phosphorous. Good idea, says Dane County Supervisor Brett Hulsey, who helped institute a county ban in 2004. Excess phosphorus is blamed for encouraging the growth of algae which clouds water and in some cases can make swimmers ill. It can also lead to fish kills and encourage the growth of invasive species. Hulsey says the ban is a small step in the right direction. The bill is proposed by state Sen. Mark Miller , a Dane County Democrat, and Door County Republican Rep. Gary Bies. Minnesota is the only state with a law on phosphorous, restricting its use on lawns and turf.