Nimblewill

Nimblewill (Muhlenbergia schreberi) is a warm-season perennial grass weed of lawns and low-maintenance turf, recognized as a thin, wiry grass that is pale green to gray-green and noticeably lighter in color than most cool-season lawn grasses. It spreads by aboveground stolons that creep along the soil surface, typically forming distinct circular patches in the turf. The leaf blades are short and arranged on the wiry stems, and the patches turn light brown or tan as the plant goes dormant in late fall and winter, then are conspicuously slow to green up again in spring, which is one of the easiest ways to spot it.

Nimblewill forms expanding circular patches of fine, wiry, pale gray-green grass that contrast sharply with desirable turf in color and texture; the patches go dormant early and green up late, leaving conspicuous tan, dead-looking areas in late fall, winter, and spring, and the spreading stolons crowd out the surrounding turfgrass, steadily reducing stand density and uniformity.

Nimblewill is a warm-season perennial grass. It overwinters as crown and stolon tissue and produces new stems and leaves from the crowns in spring, while seed produced the previous year germinates in late spring to early summer. It reproduces both by seed and vegetatively by stolons, which creep across the soil surface and root to form expanding patches; vegetative spread by stolons is the main way established infestations enlarge. The plant makes rapid vegetative growth through summer and enters dormancy in late fall.

Nimblewill colonizes thin turf and is most troublesome in lawns, parks, and low-maintenance areas, spreading by stolons into any opening in the canopy. It is favored by conditions that thin cool-season turf and tolerates a range of sites; once established, its stolon network lets it persist and expand even where the surrounding turf is otherwise reasonable. Its distinct dormancy pattern makes infested patches obvious in early spring and late fall when they are tan against green turf.