USDA Agricultural Research Service scientists have been studying how to remove excess nutrients from manure lagoons by growing plants on floating mats. One research phase to extract excess nitrogen and phosphorus from wastewater has been completed and a second is under way

So far, cattail grew the best on full-strength wastewater, produced the most biomass, and removed the most nutrients. Studies showed that harvesting cattail from the floating rafts could remove an average of 493 grams of nitrogen and 73 grams of phosphorus per square meter per year. Several different plant species are good candidates, including St. Augustine grass, coastal Bermudagrass, and giant reed. All are potential sources of bioenergy fuel.

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