2,4-D Herbicide & Similar Ingredients For Lawns

• Lawn-specific herbicide products with active ingredient 2,4-D and similar ingredients kill dandelion and other broadleaf (soft stems and leaves) weeds. They don’t damage lawns when used according to directions.
• Lawn-specific herbicide ingredients can also damage nearby desired plants if the roots extend into the lawn area.
• If tree or shrub (bush) roots extend under your lawn, avoid using products with 2,4-D in the root zone of the desired plants.
• Follow the label to avoid damaging the roots of trees and shrubs.

2,4-D, triclopyr & Similar Ingredients

• Some herbicide products with 2,4-D and triclopyr (ester formulations) become a vapor when applied on hot days.
• High temperatures and low humidity increase vaporization (chemicals turn into gases).
• The vapor can damage nearby plants. Check the label for temperature limits.

Glyphosate & Other Non-selective Herbicides

• Herbicide products with the active ingredient glyphosate will damage most grasses and broadleaf plants. Don’t let spray get near plants you want to keep.
• Glyphosate is a non-selective herbicide. It kills most plants.
• Broad-spectrum herbicides are useful for areas such as patios, walkways, driveways, and fence lines.
• Some non-selective herbicides can even be used around fruits, vegetables, flowers, trees, and shrubs, but only if the label says so.
• Don’t let the spray contact plants you want to keep. They will get damaged by the herbicide.

Non-selective herbicide ingredients include:

• Glyphosate
• Imazapyr
• Diquat dibromide
• Contact herbicides will damage leaves and stems the spray directly contacts. Contact herbicides don’t kill the roots of plants they contact.

• Many weed killers (herbicides) can be harmful to nearby non-target plants. Some will prevent plants from growing in treated areas for months.
• Look for DIRECTIONS FOR USE. They may be inside a booklet or pamphlet.
• Follow the instructions closely to minimize risks to non-target plants.

What the Label Says: “Do not use before planting lawns, flowers, or other plants because this product remains active in soil for up to one year.”

What That Means: This is often called a “plant-back restriction.” It means you cannot expect plants to thrive in treated areas until after a period of time has passed. These products are intended to be used in places where plants are not wanted, such as driveways.

What the Label Says: “Do not collect grass clippings for mulch or compost. Do not send clippings to a compost facility.”

What That Means: This is often called a “compost restriction.” It means the product may remain active, even after composting. People have damaged their gardens by using compost with traces of the active ingredients clopyralid and aminopyralid, in particular.

See Herbicide-Contaminated Compost and Soil Mix: What You Should Know — and What You Can Do About It  (OSU Extension Service) for more information.

What the Label Says: “Under conditions which are conducive to evaporation (high temperatures and low humidity), vapors from this product may injure susceptible crops nearby.”

What That Means: Immediately after spraying, and even days later, this product can evaporate from treated surfaces. If the wind doesn’t blow the vapors away, they may hang in the air and damage nearby plants. Often, grapes, flowers, and vegetable plants are highly sensitive to the vapors.

What the Label Says: “Do not apply this product in areas where the roots of desirable plants may extend unless injury can be tolerated. Root zones can extend well beyond the tree canopy.”

What That Means: When attempting to control weeds, it’s possible to damage trees and shrubs. In La Pine, Oregon, several trees were killed after the first rains in October washed herbicide residue down from the surface to the trees’ root zones.