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You are here: Home / Manager's Tool Kit / Early Detection and Rapid Response / The Early Detectives / The Nature Conservancy - North Fork Weed Coop
Manager's Tool Kit
Early Detection and Rapid Response

The Early Detectives: How to Use Volunteers Against Invasive Species, Case Studies of Volunteer Early Detection Programs in the U.S.

The Nature Conservancy - North Fork Weed Coop

Contacts: Heather Knight, The Nature Conservancy
Phone: (970) 416-8620


In the winter of 1998, a group of citizens, state agencies and interest groups began to meet and discuss the issue of invasive species in the 386,000 acres around the North Fork of the Poudre River in Colorado. Citizens, the local Nature Conservancy Chapter and other agencies officially began the North Fork Weed Cooperative in the spring of 1999.

The members of the coop are usually landowners who agree to monitor their land for invasives. The staff at the North Fork Weed Coop educates these individuals about the priority invasive species that could pop up on their property. The size of a member's monitored area depends on the size of their property. The members of the coop are responsible for monitoring their own land for nine priority invasive species.

If they find any invasives on their property, they either use a GPS unit or just detailed descriptions to map the exact location of the spots and then report to the North Fork Weed Coop.

The staff at the coop determines what the proper mix of integrated weed management methods will be. These methods of control include mowing, grazing, use of herbicides, bio-control, or fire. The staff looks at what types of native organisms are at the location, the size , the potential spread of the invasion and whether or not to treat it all, or just the perimeter and prohibit the spread of the species.

The staff then executes the treatment plan and monitors the spot for a year. If the patch of invasives has returned, then the staff will adjust the plan accordingly and re-monitor the spot. This program of the coop results in the active monitoring of roughly one half of the entire North Fork area, which includes both public and private lands. Through the coop, the program has been highly successful in eliminating the priority invasive species in the area.

Volunteers also assist in monitoring the public lands of the area though this is not the major purpose of the coop. Volunteers will go out in small teams to locate any invasives in small areas of the public lands. In addition, volunteers will map the location of invasives then, send that info back to the coop. Depending on the size of the invasion, the coop will either deal with the problem by itself or contract out the control applications to local businesses. This has been a successful method for eradicating the priority species on the public lands before they can become established.

The North Fork Weed Coop is also working to compile a database of surveys of the watershed. This public database includes physical characteristics of the invasives and control methods and it assists the members of the coop who design their own management plans for their property. In addition, through the database and newsletters that provide information about how the invasives are to be managed, the coop tries to educate the entire community about the problems associated with invasives.

Information about eighteen of the most prominent invasive species in the area can be found in additional pamphlets. These pamphlets, which include illustrations of the weeds, provide information concerning the ecological roles and control methods for each individual species.

For its members and local citizens, the coop holds two-day workshops on weed management plan writing where the participants learn to set goals and objectives to manage their individual property. Another opportunity for education through the North Fork Weed Coop is its "weed tours." In these full-day tours, eight to fifteen volunteers and members visit neighboring properties that have been affected by invasive species. The group will learn to identify species as well as methods to eradicate the species. These tours give the volunteers the chance to learn about invasives by actually seeing projects of fighting invasives in action. The coop advertises these tours in the local newspapers as well as on its web site.


The main success of this early detection and volunteer program is that one half of the entire 386,000 acres of the North Fork area is now actively monitored. The goal of its monitoring program is to find invasives and then, initiate a rapid response. Through the work of the 60 members and volunteers, the invasive problems of both the private and public lands are found and responded to, in a timely fashion. The total amount of coverage of this small organization is very high compared to other weed monitoring efforts.

Suggestions for other new organizations

Heather Knight of the coop suggests that a beginning invasive monitoring program first identifies its key partners in the area and gain the partners' full support. It is vital for the partnership to agree on the short and long-term goals in the beginning. From there, the partnership needs to decide on the tools needed to achieve the goals. If the coop could go back to square one, Knight would have established a larger group of partners to have a bigger base of participants. In addition, Knight recommends that groups establish a strategic plan for a steady source of revenue
Another suggestion is to start small in the size and objectives of the monitoring process. Through a small beginning, the core values of the organization will become established and grow as the group grows. It is important for an organization to be highly adaptive. When working with volunteers, Knight suggests that a group needs to be adaptive to the needs and motivations of their volunteers. This indicates that the needs of the volunteers may change and the program staff must be patient and deal with those changes. People skills are vital to make the volunteers feel appreciated.

Finally, it helps to have a large and experienced co-sponsor. The Nature Conservancy assisted in getting the coop off the ground. However, Knight indicated that the survival of the coop is based on community involvement. Once the community backed the North Fork Weed Coop, the Nature Conservancy's role was minimized to allow the community to take control of the program.

Challenges of the Program

The biggest obstacle for the coop is a small number of people are doing most of the work and the probability of burn-out is very high. The coop is also concerned about burning out its members and volunteers. With more members, the workload on the volunteers would decrease and the amount of revenue for the coop would increase.


The North Fork Weed Coop actively uses GPS units to map the exact locations of invasive species. Once the coordinates are loaded into the GPS unit then, they are downloaded into a GIS software package to produce maps of the area. These maps are then loaded into the public database.

Choosing target species

Priority invasive species are based on four major criteria:

1) Native species in the area
2) The most sensitive sites to invasive species infestation in the watershed
3) Species that can be easily controlled
4) Where they perceive the coop can the biggest impact

They will choose to fight a new but extremely dangerous invasive before they start to tackle a well-established invasive. Through these criteria, the coop decided on nine priority species (below).

When the volunteers find the priority species on their property, they must decide whether or not the infestation is an individual occurrence or an established spread of the invasive species. The coop includes additional information in its training manuals about other invasive for the volunteers to be watching for. However, the volunteers are taught to look closely for the nine priority species.


Volunteers attend a six-hour methods workshop on how to identify, record the location of, and eradicate the priority invasive species. This workshop is both classroom and field based. At the completion of the workshop, the volunteers will be able to effectively manage and monitor their own property. In addition, the volunteers are given informational packets detailing the biology and descriptions of the nine priority species.

Quick Facts

Number of Volunteers: approximately 60 volunteers per year, 500 people on the mailing list. Paid members (27 individual, 7 governmental agencies, 3 non-profits)

Operating Budget: $10,000 to $75,000 depending on the number and size of grants and donations

Species Targeted:

Dalmatian Toadflax (Linaria dalmatica)
Yellow Toadflax (Linaria vulgaris)
Leafy Spurge (Euphorbia esula)
Russian Knapweed (Acroptilion repens)
Diffuse Knapweed (Centaurea diffusa)
Spotted Knapweed (Centaurea maculosa)
Cheatgrass (Bromus tectorum)
Canada Thistle (Cirsium arvense)
Field bindweed (Convolvulus arvensis)

Habitats Patrolled: Fields around the North Fork of the Poudre River Watershed, Poudre River

Location: USA, Colorado

Report prepared by: Brian Webb

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Last Modified: Jan 06, 2017
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