How to Kill Barnyardgrass in Kentucky Bluegrass Without Hurting Your Lawn
Direct Agronomic Answer
To selectively kill Barnyardgrass in Kentucky Bluegrass without damaging your turf, apply Drive XLR8 (Quinclorac 18.92%), Acclaim Extra (Fenoxaprop-p-ethyl 6.59%) when air temperatures are between 60°F and 85°F.
Fenoxaprop (Acclaim Extra) is also highly effective in tall fescue and Kentucky bluegrass.
1. Labeled Safe Herbicides That Kill Barnyardgrass in Kentucky Bluegrass
| Recommended Product | Active Ingredient & Group | Application Temp (°F) | Surfactant & Mixing Protocol | Where to Buy |
|---|---|---|---|---|
| Drive XLR8 EPA Reg. 7969-272 |
Quinclorac 18.92% Group 4 (Synthetic Auxin / Quinoline Carboxylic Acid) |
60°F – 85°F Rainfast: 1h |
Requires Methylated Seed Oil (MSO) surfactant at 1.5 tbsp (0.75 fl oz) per gallon of water for effective cuticle penetration on multi-tiller crabgrass. | Check Price at DoMyOwn View on Amazon |
| Acclaim Extra EPA Reg. 432-950 |
Fenoxaprop-p-ethyl 6.59% Group 1 (ACCase Inhibitor) |
60°F – 85°F Rainfast: 1h |
Add Non-Ionic Surfactant (NIS) at 0.5 tsp per gallon only when targeting mature multi-tiller Goosegrass or Japanese Stiltgrass. Never tank-mix with 2,4-D (causes antagonism). | Check Price at DoMyOwn View on Amazon |
3. Optimal Seasonal Timing & Temperature Thresholds
Apply post-emergents early in summer when plants have 1 to 3 tillers.
Pre-emergent Prodiamine applied in spring stops seeds before emergence.
4. Diagnostic Checklist: Confirm It Is Barnyardgrass Before Spraying
- Thick, robust stems often reddish-purple tinted at the base with no ligule (completely ligule-less)
- Broad, flat, smooth blades with a conspicuous white midrib
- Coarse, branched, purplish seedheads with short to long stiff awns
Not 100% sure? Use our AI Photo Weed Scanner or review the full Barnyardgrass Botanical Profile.