Eurasion Water Milfoil (Part 6) Eurasion water milfoil is an exotic plant that grows into thick mats on a lake’s surface. It hampers fishing, boating and swimming, and provides excess escape cover for small fish so predators cannot feed on them. When water milfoil gets in a lake, the result is a weed-choked water body with mostly small fish. This exotic plant crowds out desirable native plants and upsets nature’s balance. Milfoil reproduces by seeds, stem fragments and root runners, and it only takes one small segment to take root in a new location and start a new infestation. In 2003 North Dakota did not have any known milfoil sites, but it has spread to about 150 lakes in Minnesota, two of which are within 100 miles of our border.