Our native blue flag iris (Iris versicolor) is a beautiful perennial that grows well on lakeshores, swamps, wet meadows and along stream beds. Now it appears this iris can be effective in controlling pollution as well. Researchers at the USDA and University of Massachusetts grew 10 different water-loving plants in a greenhouse setting. Over a three-month period, they measured how much of four common pesticides were absorbed by each.
The top performers were blue flag iris, eastern gamma grass, and big blue stem. Blue flag iris also had the added benefit of being an attractive ornamental. If you are concerned about pesticides running into your property from your neighbor's yard, local farm, or golf course, consider planting a vegetative filter strip of this iris to help keep your groundwater clean.
For more information on this research, go to: Journal of Environmental Quality. Photo courtesy of the USDA.