Due to their limited land base, North Carolina has examined various means of treating swine wasterwater in order to reduce nutrient content, in particular nitrogena dn phosphorus. One method as been the incorporation of plant species including: weater hyacinth, duckweed and microalgae. Duckweed is the most practical of these alternatives, a high nutrient absoprtion rate, fast plant growth and a high protein compostion (allowi it to be used as alternative feedstuff).