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
- Imazapic
- Chemical class
- ALS (acetolactate synthase) inhibitor, WSSA Group 2; Plateau contains it as the ammonium salt, equal to 2 pounds of imazapic acid per gallon.[1][2]
- Mode of action
- WSSA Group 2: Acetolactate synthase (ALS/AHAS) inhibitors[2][1]
- Signal word
- Plateau Herbicide: Caution[1]
Where Plateau can and can't go
Plateau is labeled for pastures, rangeland, CRP land, rights-of-way, airports, golf courses and other non-residential turf. The label says not to use it on residential lawns, not to treat inside irrigation ditches, and not to apply it through irrigation systems.[1]
Hay can't be cut from a treated area for seven days. Newly seeded or sprigged grass should not be treated except as the label's revegetation section allows.[1]
Grass tolerance and yellowing
Some turf may yellow for 2 to 4 weeks after a growing-season application. Tolerance of desirable grasses drops when they are stressed by insects, disease, shade, poor drainage or weather.[1]
Where it is used
Spraying growing weeds is the method of choice in most cases, especially for perennials, and the spray needs an adjuvant such as a surfactant or methylated seed oil. It is rainfast one hour after application.[1]
Symptoms are slow. Yellowing starts in the newest leaves, and complete kill may take several weeks. Adequate soil moisture also gives residual control of weeds that germinate later.[1]
For leafy spurge, the label favors 8 to 12 ounces per acre in late summer or fall with methylated seed oil, applied before frost stops the plant's milky sap.[1]
Don't rinse spray equipment on or near desirable trees and ornamentals or over their roots, and test a small area first when treating near desirable trees or shrubs.[1]
Products and registrations
| Product | Registrant | EPA Reg. No. | Active % | Formulation | Signal word |
|---|---|---|---|---|---|
| Plateau Herbicide[1] | BASF Agricultural Solutions US LLC | 241-365 | 23.6% | aqueous solution | Caution |
Label rates
| Product | Use | Pests | Rate |
|---|---|---|---|
| Plateau Herbicide | Pastures, rangeland, Conservation Reserve Program land and noncrop areas such as rights-of-way, fence rows and industrial turf | Annual and perennial grasses and broadleaf weeds, including cheatgrass, downy brome, medusahead, leafy spurge and tall fescue | 2–12 oz product per acre[1] The label lists rates in ounces per acre that vary by site and target, from 2 ounces for seedhead suppression up to 12 ounces for perennials such as leafy spurge. Never more than 12 ounces per acre in one year. |
Safety and environmental hazards
People
Signal word CAUTION. Avoid breathing spray mist and avoid contact with skin, eyes or clothing. Applicators wear long sleeves, long pants, chemical-resistant gloves, and shoes plus socks.[1]
Pets
The label groups people and domestic animals under the same CAUTION statement, and it says to keep out of treated areas without protective clothing until sprays have dried.[1]
Bees and pollinators
The label carries no direct bee toxicity warning, but it says the product is toxic to plants and may harm the forage and habitat of pollinators beside the treated site.[1]
Fish and water
For land use only. Imazapic can leach to shallow groundwater and has a high runoff potential for several months, so the label advises a vegetated buffer strip near ponds and streams and avoiding application when rain is forecast within 48 hours.[1]
Resistance
The label notes that weed resistance to Group 2 herbicides is common. It advises tank-mixing or following up with an herbicide from a different group and scouting for escapes.[1][2]
Common questions
- Can I use imazapic on my home lawn?
- Not with Plateau. Its label states plainly that it is not for use on residential lawns.[1]
- How much Plateau is applied per acre?
- Between 2 and 12 ounces per acre depending on the site and weed, with a cap of 12 ounces per acre per year.[1]
- How fast does imazapic work?
- Treated plants stop growing soon after spraying, but yellowing and death can take several weeks to show.[1]
Sources
- U.S. EPA Pesticide Product Label System, “Plateau Herbicide label, EPA Reg. No. 241-365 (EPA-stamped, Nov. 30, 2023).” www3.epa.gov/pesticides/chem_search/ppls/000241-00365-20231130.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)