The label is the law. Read your product's label before you mix or apply; the rates here come from the labels listed under Sources.
- Active ingredient
- Triclopyr (as the triethylamine salt) (CAS 55335-06-3)
- Chemical class
- Pyridine carboxylic acid herbicide; a synthetic auxin (WSSA Group 4) that disrupts plant growth.[2]
- Mode of action
- WSSA Group 4: Synthetic auxins (pyridine carboxylic acids)[2]
- Signal word
- Ortho Brush-B-Gon Brush Killer (concentrate): Caution[1]
Poison ivy and tough vines
Poison ivy, poison oak, blackberries and honeysuckle may need a second treatment if regrowth appears. Contact with poison ivy or oak can cause an allergic reaction any time of year.[1]
Where it is used
Spray when weeds are leafed out and actively growing, wetting all leaves, stems and trunks with a low-pressure, coarse spray. Rain 2 hours later won't reduce effectiveness.[1]
It kills desirable plants too: shield them with cardboard or plastic, or cut weeds at the base and treat the stump instead. Foliage spraying isn't recommended for weeds in lawns.[1]
For stumps, brush the product undiluted onto the entire freshly cut stump, including the cut surface, trunk and exposed roots.[1]
Do not use on or around food or feed crops, or apply when wind exceeds 10 mph or is gusting.[1]
Products and registrations
| Product | Registrant | EPA Reg. No. | Active % | Formulation | Signal word |
|---|---|---|---|---|---|
| Ortho Brush-B-Gon Brush Killer (concentrate)[1] | The Scotts Company | 239-2491 | 8.0% | concentrate | Caution |
Label rates
| Product | Use | Pests | Rate |
|---|---|---|---|
| Ortho Brush-B-Gon Brush Killer (concentrate) | Brush and vines around homes, outbuildings, fences and trails | Poison ivy, poison oak, kudzu, blackberry, honeysuckle and woody brush | 4 fl oz per gallon of water[1] One gallon covers 100 sq ft of dense brush up to 400 sq ft of lighter brush. Don't exceed 5.4 fl oz of product per 100 sq ft in a year. |
How to apply it, step by step
1. Protective gear
- Wear a long-sleeved shirt, long pants, shoes and socks when applying it; it is harmful if absorbed through the skin, causes moderate eye irritation and can cause skin allergies in some people.[1]
- Handle dead poison ivy or poison oak with rubber gloves, since contact can cause a reaction at any time of year, and throw the plants and gloves out in tightly sealed garbage bags.[1]
- Wash your hands before eating, drinking or using the toilet, and wash contaminated clothing before wearing it again.[1]
2. Before you spray
- It kills the plants and grass you want as well, so the foliage spray isn't for weeds in lawns, and it isn't for use on or around food crops or grazing areas.[1]
- Spray only when the air is calm: not when the wind averages over 10 mph or is gusting.[1]
- Don't apply it directly to water; it can reach groundwater where soils are permeable and the water table is shallow.[1]
- Keep people and pets out of the area while you spray.[1]
3. Mixing
- For brush, mix 4 fl oz per gallon of water in a tank sprayer (or set an Ortho Dial 'N Spray to 4 oz).[1]
- For stumps and cut vines, use it undiluted, straight from the bottle.[1]
4. Applying
- Spray brush when it is leafed out and actively growing, using low pressure and a coarse spray, until leaves, stems and trunks are thoroughly wet; a gallon covers about 100 sq ft of dense brush or 400 sq ft of light brush.[1]
- Shield nearby plants with cardboard or plastic, or cut the weeds at the base and treat them as stumps; if you hit a plant you want, rinse it off with water right away.[1]
- For vines on poles, fences or mature-barked trees (no green under the bark when you scratch it), spray the vines up to 3 to 4 feet; on shrubs or green-barked trees, cut the vine at the base and paint the cut instead.[1]
- For stumps, paint the whole freshly cut stump with undiluted product: cut surface, remaining trunk and exposed roots. Don't reuse the brush; wrap it in newspaper and throw it away.[1]
- Don't use more than 5.4 fl oz of product per 100 sq ft in a year from all applications.[1]
5. After you spray
- Keep people and pets out of the treated area until the spray has dried; rain 2 hours after application doesn't reduce how well it works.[1]
- Wilting or yellowing shows up in 2 to 6 weeks; tough plants such as poison oak, poison ivy, blackberries and honeysuckle may need a second treatment if they regrow.[1]
- Rinse the sprayer over the treated area, not near a drain.[1]
First aid
- On skin or clothing, take off contaminated clothing and rinse the skin with plenty of water for 15 to 20 minutes.[1]
- In the eyes, hold them open and rinse slowly and gently with water for 15 to 20 minutes, removing contact lenses after the first 5 minutes, then call a poison control center or doctor; the label's emergency number is 1-877-465-5161.[1]
Storage, spills and disposal
- Store it in its original container out of reach of children and pets.[1]
- Put an empty bottle in the trash or recycling; for a partly full one, call your local solid waste agency, and never pour product down a drain.[1]
From the safety data sheet
- This sheet is for a product sold under the same EPA registration as Brush-B-Gon Brush Killer; the concentrate is a clear, odorless liquid.[3]
- The SDS uses the signal word Warning: it causes eye irritation and may cause an allergic skin reaction.[3]
- If it gets in the eyes, flush them with plenty of water for at least 10 minutes, lifting the eyelids and removing contact lenses, and get medical attention if irritation persists.[3]
- After skin contact, wash with plenty of soap and water, remove contaminated clothing and shoes, and get medical attention.[3]
- Keep spills and runoff away from soil, waterways, drains and sewers, and store the product in its original container out of direct sunlight in a dry, cool, well-ventilated place.[3]
Safety and environmental hazards
People
Signal word CAUTION: harmful if absorbed through the skin, causes moderate eye irritation and may cause skin sensitization. Wear long sleeves, long pants, shoes and socks.[1]
Pets
Keep people and pets out during application and until the spray has dried.[1]
Bees and pollinators
The label's environmental statement focuses on water: don't apply directly to water or let it run into drains or surface water.[1]
Fish and water
Do not apply directly to water or allow it to enter storm drains, gutters or surface waters.[1]
Common questions
- How long does Brush-B-Gon take to kill poison ivy?
- The label says wilting or yellowing appears in 2 to 6 weeks, and hard-to-kill species may need retreatment.[1]
- Can I use triclopyr near my vegetable garden?
- The label says not to use it on or around edible crops and to keep drift off plants you want to keep.[1]
- Will rain wash it off?
- Rain 2 hours after application won't reduce effectiveness, according to the label.[1]
Sources
- U.S. EPA Pesticide Product Label System, “Ortho Brush-B-Gon Brush Killer label, EPA Reg. No. 239-2491 (EPA-stamped, Aug. 6, 2024).” www3.epa.gov/pesticides/chem_search/ppls/000239-02491-20240806.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)
- The Ortho Group, “ORTHO MAX Poison Ivy & Tough Brush Killer Concentrate Safety Data Sheet (The Ortho Group, version 1.5, revised December 4, 2015; EPA Reg. No. 239-2491, the Brush-B-Gon registration on this page, which EPA lists this name under; copy hosted by DoMyOwn).” www.domyown.com/msds/ortho.pdf (accessed 2026-10-17)