Herbicide · reference
Lawn Weed Killer with Trimec
The classic three-way lawn herbicide — 2,4-D + MCPP + dicamba. This "Trimec" combination is the standard for broadleaf weed control in turf you want to keep, because it kills a wide range of weeds while leaving most common lawn grasses unharmed.
- Maker
- Southern Ag (Trimec is a PBI/Gordon trademark)
- Active
- Mecoprop-p (MCPP-p) DMA salt 5.30% + 2,4-D DMA salt 3.05% + Dicamba DMA salt 1.29%
- MoA group
- WSSA Group 4 (all three are synthetic auxins)
- Net contents
- 1 quart (.946 L)
- Coverage
- 1 quart covers up to 12,800 sq ft
- Signal
- caution
01Usage
What it's for and where it goes.
- Targets (label): Dandelions, chickweed, knotweed, plantain, henbit, spurge, and many other broadleaf lawn weeds.
- Safe on turf: Bahiagrass, bermudagrass, bentgrass, buffalograss, bluegrass, centipedegrass, ryegrass, fescue, St. Augustinegrass. Do not use on Floratam St. Augustinegrass in Florida.
- Coverage: 1 quart treats up to 12,800 sq ft.
- Water-based product.
02Efficacy
How well it actually works.
- The three-way mix broadens the spectrum well beyond any single active — the combination catches weeds that one component alone would miss.
- Dicamba adds root uptake and reaches some weeds 2,4-D/MCPP struggle with.
- Growth-regulator action; weeds distort and die over several days.
03Best at killing
What it's genuinely strongest on in real use.
- Broad-spectrum lawn broadleaves — the 2,4-D + MCPP + dicamba "Trimec" three-way is the standard for cleaning up a lawn you want to keep: dandelion, chickweed, knotweed, plantain, henbit, spurge and clover all fall to it, while common turf grasses are spared. The combination catches weeds any single active would miss, and dicamba's root uptake reaches a few the others struggle with (Purdue Turf, three-way broadleaf control).
- Growth-regulator action — weeds distort and die over several days, not a fast burn.
04Dangers
What it can hurt — read this before you reach for it.
- Signal word CAUTION.
- Dicamba mobility: dicamba can move in soil and be taken up by tree/shrub roots — avoid spraying over the root zones of desirable trees, especially near beds.
- Off-target drift kills garden/ornamental broadleaves. Keep away from vegetables and flowers.
- Keep out of reach of children. Avoid skin/eye contact.
05🐾 Dogs & re-entry
Pet safety — toxicity and how long until a dog can be back on it.
🐾 Pet safety — read before you let the dog out
- Toxicity: the mix is slightly-to-moderately toxic; 2,4-D dogs are more sensitive (NPIC 2,4-D), and dicamba signs in dogs/cats are "shortness of breath, muscle spasms and... a lot of saliva" (NPIC Dicamba); MCPP is EPA toxicity class III (slightly toxic).
- When safe again: NPIC (2,4-D and dicamba both) says stay off treated grass until the leaves are dry. A peer-reviewed study detected these same actives in pet-dog urine after home lawn treatment, with longer residence on dry vs. green grass (Knapp et al., Sci Total Environ 2013) — so the cautious default is dry plus 24–48h and a rain/irrigation.
General guidance. Confirm the label's re-entry interval and ask your vet; when unsure keep dogs off until fully dry.
06Storage
How to keep it, and keep it separate.
- Water-based — keep from freezing (per label). This is the key storage note; freezing can ruin the emulsion.
- Store in original container, tightly closed, cool, away from children, food, feed.
- Long shelf life if unfrozen and sealed.
landscape.gf.cx · chemicals · lawn-weed-killer-trimec · filed 2026-07-23 · read off the label — verify every rate against the booklet