The label is the law. Rates and restrictions below are taken from the product labels listed under Sources. Your product's own label governs; read it before you mix or apply. Mixing calculator · Disclaimer
- Active ingredient
- Clopyralid (as the monoethanolamine salt)
- Chemical class
- Pyridine carboxylic acid herbicide; a synthetic auxin (WSSA Group 4) that acts like the plant hormone auxin and disrupts growth.[2][1]
- Mode of action
- WSSA Group 4: Synthetic auxins (pyridine carboxylic acids)[2][1]
- Signal word
- Lontrel Turf and Ornamental Herbicide: Caution[1]
Compost and grass clipping warning
The label is blunt: don't send grass clippings from treated turf to a compost facility, and don't collect them for mulch or compost. Applicators must tell landowners or property managers not to compost the clippings.[1]
It also warns that residues in plant tissue that hasn't fully decayed can affect sensitive crops planted later, such as legumes.[1]
Not for home lawns
Lontrel Turf and Ornamental must not be used on residential turfgrass; lawn uses are limited to non-residential sites. In California and Washington, turf uses are restricted to golf courses (the turf section also allows noncrop areas), and sale and use are prohibited in Suffolk and Nassau counties, New York.[1]
Where it is used
Spray small, actively growing weeds. For Canada thistle and knapweeds, wait until most basal leaves are out but before bud stage, and don't cultivate for 14 to 20 days afterward.[1]
It is rainfast in 2 hours. Wet leaves at spraying time may reduce control, and only weeds already up when you spray are affected.[1]
In landscape beds, use only spot or directed sprays, and keep it off exposed roots and suckers of legume trees such as redbud, locust and mimosa, and of linden.[1]
Don't reseed treated turf for 3 weeks, and avoid planting susceptible broadleaf plants for 10.5 months, or 18 months if soil organic matter is under 2%.[1]
Products and registrations
| Product | Registrant | EPA Reg. No. | Active % | Formulation | Signal word |
|---|---|---|---|---|---|
| Lontrel Turf and Ornamental Herbicide[1] | Corteva Agriscience, LLC | 62719-305 | 40.9% | soluble liquid concentrate (3 lb acid equivalent per gallon) | Caution |
Label rates
| Product | Use | Pests | Rate |
|---|---|---|---|
| Lontrel Turf and Ornamental Herbicide | Non-residential turf (golf courses, parks, sod farms), landscapes, field nurseries, Christmas trees and noncrop areas | Clover, black medic, dandelion, Canada thistle, knapweeds, oxeye daisy, ragweed and other broadleaf weeds | 0.1–0.5 fl oz product per 1,000 sq ft[1] 1/10 to 1/8 fl oz for black medic and dock, 1/8 to 1/5 fl oz for clover, 1/4 fl oz for dandelion and Canada thistle, and up to 1/2 fl oz for weeds it only suppresses. Max 1 1/3 pint per acre per year. |
Safety and environmental hazards
People
Signal word CAUTION: causes moderate eye irritation and is harmful if absorbed through the skin. Applicators wear long sleeves, long pants, waterproof gloves, shoes, socks and protective eyewear.[1]
Pets
The label's entry rule is to keep unprotected people out of treated areas until sprays have dried; it gives no separate pet statement.[1]
Bees and pollinators
The label has no bee or pollinator statement; its environmental warnings cover water and groundwater.[1]
Fish and water
Don't apply to water or where surface water is present. Clopyralid can seep through soil into groundwater, so the label advises against sandy, fast-draining soils over shallow water tables.[1]
Common questions
- Can I compost grass clippings after clopyralid?
- No. The label forbids sending clippings from treated turf to a compost facility or collecting them for mulch or compost.[1]
- Can I use Lontrel on my lawn at home?
- No. This label restricts turf and lawn use to non-residential sites such as golf courses, parks and sod farms.[1]
- Does clopyralid kill clover?
- Yes. Red, hop, white and sweet clover are listed at 1/8 to 1/5 fl oz per 1,000 sq ft.[1]
Sources
- U.S. EPA Pesticide Product Label System, “Lontrel Turf and Ornamental Herbicide label, EPA Reg. No. 62719-305 (EPA-stamped, Jul. 23, 2020).” www3.epa.gov/pesticides/chem_search/ppls/062719-00305-20200723.pdf (accessed 2026-10-06)
- Weed Science Society of America, “Summary of Herbicide Mechanism of Action According to the Weed Science Society of America.” wssa.net/wp-content/uploads/WSSA-Mechanism-of-Action.pdf (accessed 2026-10-06)