Goals of the Noxious Weed Management program are to:

  • Prevent establishment of invasive non-native plant populations.
  • Manage Open Space properties to reestablish and maintain healthy, diverse ecosystems.
  • Increase effectiveness of noxious weed control by implementing watershed management approach and utilizing adaptive weed management techniques.

In compliance with Title 35 Article 5.5, Colorado Noxious Weed Act, The City of Westminster employs integrated methods to manage all Colorado Department of Agriculture listed noxious weeds which are present within their properties.  Integrated Pest Management strategy assists to diagnose thresholds for management of pest, identify/inventory/monitor target species, determine prevention and planning, and direct appropriate control methods. 

Four of 36 CDA listed species in our City are classified as List A, which mandates management with the goal of eradication.  List A species are: Hairy willow-herb (Epilobium hirsutum), Japanese knotweed (Polygonum cuspidatum), Myrtle spurge (Euphorbia myrsinites), and Purple loosestrife (Lythrum salicaria).

The five main aspects to noxious weed management:

Educational - Provide information and increase awareness of the detrimental effect of non-native invasive species. For more information, visit:
Colorado Department of Agriculture
CSU Extensions 
Colorado Weed Management Association 
CSU Extensions Natural Resources 

Biological - Treatments include release of effective obligatory insects and grazing with goats. Biological Controls

Cultural - Cultural control involves cultivation of desirable species at sites where weeds have been effectively controlled in effort to reduce reestablishment of noxious weeds.
Desirable Species Control 

Mechanical - Utilize mechanical and physical treatments, such as mowing, hand pulling and prescribed fire.

Chemical - Targeted applications of selective herbicides using the lowest effective recommended rate.

Additional Resources:

Hairy Willow Herb Facts

Knot Weeds Facts

Myrtle Spurge Facts

Purple Loosestrife Facts

Contact Us:

Liam Cullinane, lcullina@westminsterco.gov