Herbicide Information

Applying Herbicide Yourself

Always Read the Label First

The Label is Federal Law. You must follow it exactly. It is illegal to apply an herbicide to your site if:

  • Your site is not included among the list of sites on the label (e.g. Range, Right-of-Way, Turf, etc.).
  • You apply it at a rate greater than that allowed by the label.
  • You do not wear proper protection.
  • It is applied in a manner otherwise inconsistent with the label instructions.

Calibrate Equipment

Always Calibrate your equipment before applying herbicide. Most herbicides come in a concentrate that must be diluted in water. Their labels usually give dilution rates in terms of volume of herbicide applied per acre. In order to determine how much herbicide to add to your tank, you must know how many gallons per acre your equipment delivers. This means you must calibrate your equipment.

License Required

Some herbicides require you to be licensed in order to apply them. These herbicides pose particular risk to the applicator and/or environment even when applied properly. They are known as Restricted Use Herbicides, and are noted as such on the label.  Although licensed to do so, Pitkin County currently does not apply any restricted use herbicides.


Always wear proper protection. This includes at a minimum: rubber-type gloves and boots, long pants, and eye protection. The label may require additional protection, such as coveralls and/or a respirator. Always read the label thoroughly before applying any herbicide.


Always use a surfactant. Also known as "stickers", surfactants help the herbicide molecules penetrate the leaves of a plant. Without a surfactant, most herbicides are much less effective. For most of the recommendations below, a non-ionic surfactant  can be used. Some herbicides will require an oil-based surfactant such as methylated seed oil. Surfactant recommendations will be noted on the herbicide label.