Weed Management

Spring 2019 Invasive Weed Management Operations are Underway

Springtime invasive weed management operations within the right-of-way boundaries along County roads are getting underway. These operations, which target diffuse knapweed, Scotch thistle and other invasive weeds in areas around the County, are expected to be completed by the early summer. This schedule is subject to change due to weather or other unforeseen factors.     

The County’s contractor, under the supervision of Natural Channel Design (NCD), is using broadleaf herbicides - Milestone® plus Clean Amine - for these spot treatment operations. These herbicides, which does not target native grasses and dries quickly, are being applied with a blue indicator dye so that treated areas can be clearly identified. Residents are asked to stay off treated areas until the herbicide has dried.

Weed removal operations for this year are scheduled along sections of County roads in the Baderville, Bellemont, Doney Park, Fernwood, Fort Valley, Herold Ranch Road, Kachina Village, Lake Mary Road, Munds Park, Williams and Schultz Flood areas. These operations, which will continue into May, target invasive weeds that include diffuse knapweed, musk thistle, Scotch thistle and bull thistle. These are highly invasive plant species that can quickly dominate areas of disturbance and outcompete desired native vegetation.

Removal of invasive weeds supports native plant revegetation. The timing of treatments is critical to prevent seed set. Spring is the optimal season for herbicide treatment as invasive weeds are small and actively growing. The County also is planning to conduct mechanical weed removal operations on County roads later this summer.

These weed management treatments will help to reduce the populations of invasive weeds along County right of way; however, they will by no means eliminate them. These treatments must be repeated for several years for the long-term successful management of these species because their seeds can live for decades in the soil. Without continued treatments, the populations of these weeds will return to pre-treatment levels within a few years.

You Can Help...

 It is critical to note that these treatments will only help to reduce the populations of invasive weeds within County right of way. As weed infestations on adjacent private property can quickly undermine these efforts, we are asking for residents’ help to continue the County’s efforts to reducing the impacts caused by these invasive species. Please regularly monitor your property and remove any new invasive weeds either manually or with herbicide treatments. Professional services range in cost from about $150 to $250 per acre for an herbicide treatment. A healthy, dense cover of native grasses is one of the best ways to help control invasive plants by providing competition for resources.

For further information on control strategies for these weeds, please see the very informative website on Northern Arizona’s Invasive Plants from the University of Arizona Cooperative Extension at: https://www.nazinvasiveplants.org/.
The County greatly appreciates your assistance in helping us to control weeds in your community. If you have any questions about weed management operations, then please contact Natural Channel Design at 928-774-2336 or email or info@naturalchanneldesign.com.