Both sedges have underground root systems containing rhizomes and underground tubers which accomplish most of the reproduction. Purple nutsedge forms chains of tubers along brownish rhizomes. Both seedheads are on triangular stems. Both spread mainly by germinating underground tubers, which are the only part of the plant that over-winters. A yellow nutsedge tuber can produce 1,900 plants and 7,000 new tubers in a single growing season 1 .
Sedges do well where soil has poor drainage.
Improve drainage through core aeration and lightening the soil. Keep turfgrass sites free from stress and vigorously competitive with sedges. Keep mowing heights as low as possible in spring and early summer when sedges are most actively growing. Fertilize cool-season grasses in the fall after frost. Use a post-emergent herbicide when nutsedge is actively growing.