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Notification Requirements for Outdoor Pesticide Applications

Notification Requirements for Outdoor Pesticide Applications

Pesticide Ordinance

The City of Boulder's Pesticide Ordinance(Section 6-10 of the Boulder Revised Code) requires that Boulder residents be notified when and where pesticides are used. The ordinance does not prohibit or limit the use of pesticides.

What are considered Pesticides?

  • Herbicides
  • Nematocides
  • Insecticides
  • Rodenticides
  • Fungicides

Responsibility for Notification

The user of pesticides is responsible for making the required notifications. The contracting party and person applying pesticides are equally responsible for notification. Note that commercial pesticide applicators must follow state requirements for pesticide notification, which is enforced by the Colorado Department of Agriculture. 


  • Contracting Party - a person or entity who arranged commercial pesticide application.
  • User of Pesticide - contracting parties and property owners.
  • Pesticide - any substance or mixture of substances intended for destroying or repelling any pest.

Types of Applications

1. Airborne applications or tree spraying (over five-feet in height) requires notification BEFORE or AFTER application.

2. All Pesticide Use requires notification immediately AFTER application EXCEPT:

  • Spot treatment of individual weeds, and the
  • Treatment area is less than 100 square-feet on a lot.

Who to Notify

BEFORE the AIRBORNE application of a pesticide, notice must be given to all occupants of adjacent properties, as illustrated below:

HOME  ( Notification Required )

HOME  ( Notification Required )

 HOME    ( Notification Required )

         HOME            ( NO Notification Required





 HOME   ( Notification Required)


 HOME  (Notification Required)

       HOME               (NO Notification Required)





HOME (Notification Required) HOME (Notification Required) HOME (Notification Required) HOME (NO Notification Required)

When to Notify

Notice must be given at least 24-hours prior to airborne application. If the application is postponed due to adverse weather conditions, the notice is valid for seven days after it is given.

How to Notify

  1. Verbal Notice to the occupants of each adjacent property, OR
  2. Written Notice to the occupants of each adjacent property, OR
  3. Post a Sign on the property to be treated. A sign is required to be posted after pesticide use.

What is Required on the Notice or Sign:

  1. Indication that pesticides will be applied.
  2. The date of application.
  3. Date the notice is given.
  4. Date the notice expires, maximum of seven days.
  5. Name and telephone number of a person who can give information about what was applied.

Sign Specifications

If you choose to post a sign on a property it must be meet the following specifications:
  1. Size - A minimum of one-foot by one-foot in dimension.
  2. Color - Dark lettering on a yellow background.
  3. Location - Posted in a conspicuous place along the principle street frontage of the property to be sprayed.
  4. Posted - At common access points of commercial buildings or apartment complexes.
  5. Length of Posting - A sign is required to be posted for at least 24 hours after pesticide use.
  6. Required Information :
    1. Date of Application
    2. Date of Notice
    3. Notice expiration date
    4. Name of Applicator
    5. Phone number