2,4-D
The most common broadleaf herbicide active ingredient, found in most lawn weed killers. It has been used since the 1940s and is highly effective against dandelions, clover, plantain, and hundreds of other broadleaf weeds. It is safe for most established lawn grasses.
2,4-D (2,4-Dichlorophenoxyacetic acid) is a synthetic auxin — a plant hormone that causes uncontrolled cell division in broadleaf plants, eventually killing them. It is the active ingredient in dozens of branded lawn weed killer products, often combined with dicamba and MCPP.
Effective against: Dandelions, clover, plantain, chickweed, ground ivy, henbit, oxalis, and hundreds more broadleaf weeds.
Safe for: Most established cool-season and warm-season grasses. Avoid new seedlings — wait until new grass has been mowed 3–4 times before applying.
Application: Works best when weeds are young and actively growing, 60–85°F.
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