Nimblewill (Muhlenbergia schreberi): Identification & Selective Herbicide Matrix
Quick Agronomic Summary
Mesotrione (Tenacity) at 5 fl oz/A applied in two to three sequential applications spaced 14 to 21 days apart selectively kills Nimblewill between 55°F and 80°F.
- Diagnostic Marker 1: Fine-textured, short, grayish-green, flat leaf blades (1 to 2 inches long)
- Diagnostic Marker 2: Wiry, decumbent stems that root at lower nodes forming dense mats
- Diagnostic Marker 3: Turns straw-brown and completely dormant in late fall and winter
What kills Nimblewill without killing Kentucky Bluegrass or Tall Fescue?
Mesotrione (Tenacity) at 5 fl oz/A applied in two to three sequential applications spaced 14 to 21 days apart selectively kills Nimblewill between 55°F and 80°F.
Nimblewill is extremely sensitive to HPPD inhibition. Mesotrione causes rapid bleaching (chlorosis) followed by plant collapse. Always add Non-Ionic Surfactant (NIS).
When is the best time to spray Nimblewill?
Apply in late spring to early summer when Nimblewill is green and actively growing, and repeat applications in late summer if regrowth occurs.
Do not treat when Nimblewill is entering winter dormancy or drought-stressed, as lack of chlorophyll synthesis prevents Mesotrione uptake.
EPA-Registered Herbicides Labeled for Nimblewill
The table below compares all selective herbicides in our database that control Nimblewill, including active ingredient groups, application temperature limits (°F), and surfactant requirements.
| Brand Name & EPA Reg. | Active Ingredient & WSSA Group | Temp Window (°F) | Surfactant & Mixing Protocol | Where to Buy |
|---|---|---|---|---|
| Tenacity EPA Reg. 100-1267 |
Mesotrione 40% Group 27 (HPPD Inhibitor) |
55°F – 85°F Rainfast: 6h |
Always apply with Non-Ionic Surfactant (NIS) at 1 tsp (5 mL) per gallon of water for post-emergent applications. Causes temporary white bleaching on susceptible weeds and turf tips. | Check Price at DoMyOwn View on Amazon |
| Pylex Herbicide EPA Reg. 7969-327 |
Topramezone 29.7% Group 27 (HPPD Inhibitor / Pyrazolone) |
55°F – 85°F Rainfast: 1h |
Must be applied with Methylated Seed Oil (MSO) at 1 to 1.5 tsp per gallon of water. Tank-mixing with Triclopyr Ester reduces white bleaching and speeds up Bermudagrass and Goosegrass mortality. | Check Price at DoMyOwn View on Amazon |
Turfgrass Compatibility Matrix for Nimblewill Herbicides
Always verify that your chosen herbicide is safe for your specific lawn grass before broadcast spraying:
How to Distinguish Nimblewill from Lookalike Weeds
| Lookalike Species | Key Botanical & Diagnostic Difference |
|---|---|
| Bermudagrass | Bermudagrass possesses both aggressive underground rhizomes and vigorous stolons, while Nimblewill spreads solely by shallow decumbent stems and roots at nodes without true deep rhizomes. |