Protecting High Quality Rangelands in Garfield County from Invasive Weed Spread

Final Report for FW05-301

Project Type: Professional + Producer
Funds awarded in 2005: $20,000.00
Projected End Date: 12/31/2008
Region: Western
State: Montana
Principal Investigator:
Eric Miller
Montana State University
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Project Information


Over the past 10 years, noxious weed occurrences have increased in Garfield County. The increase can be attributed to: increased vehicle traffic on the bisecting highways, hunter activity on secondary and private roads, and increased reliance on out-of-county hay. In an effort to maintain and reduce the current noxious weed levels in Garfield County, the Weed Prevention Area (WPA) concept was developed. The principle is to limit new infestations by increasing landowners and visitors’ awareness of the detrimental impacts of noxious weeds to the environment. To track the weed status of lands, GPS technologies are used to map weed locations and to verify locations and acreages of non-infested lands.


Noxious weed encroachment has been an ongoing problem in the western US since the early 1900s. (A) In Montana, the spread of spotted knapweed has been documented since 1920. Spotted Knapweed started in Missoula County and today infests every county in the State. Montana currently list 32 plant species in 4 categories as noxious weeds in need of management. Economic and ecological impacts represent a tremendous cost to state each year. Current estimates place the cost of noxious weed control in Montana at between 200 and 300 million dollars annually, with an estimated 42 million dollars for the control of spotted knapweed alone. In addition it has been estimated weeds cost farmers in excess of 100 million dollars annually in control expenses and decreased production.
In 2005, Shelley et al reported noxious weeds negatively impact the native ecology by; displacing native plants, reducing biodiversity, altering the normal ecological processes, decreasing wildlife habitat, reducing recreational value of lands and increasing soil erosion and stream sedimentation.
In recent years there has been a shift in the paradigm of weed control. Instead of the historical thought of waiting until there is an infestation and treating the situation, today land managers are working on the prevention concept. There are still vast stretches of land that are either weed free or have minimal noxious weed impacts. In these areas it is for both labor and economically cost effective and proactive to keep new invaders from becoming established. Prevention is the least expensive weed control method and most effective means to halt further weed spread. There have been several publications in recent years touting the benefits of weed prevention. The methodologies of these strategies are similar and call for many of the following practices:
Education of land owners, land users and the general public; proper weed identification; aggressive monitoring of high probability sites on a regular basis; the use of weed seed free products; aggressive control plans and eradication of new weed infestations; prevent movement of products from weed infested areas to non-weed infested areas; mapping weed areas; limiting access to vehicle travel; and utilizing best management practices of grasslands.
Garfield County Montana is comprised of 70% rangeland. The vast majority of the rangeland is free of noxious weeds, which provides both ecological and economic benefits for all users. Benefits include a decreased cost of production and increased carrying capacity for livestock producers, native habitat for wildlife and native plant and grass species for recreationalists.
Widespread noxious weed infestations have not historically been a problem in Garfield County due to the county’s remoteness and lack of bisecting waterways. Over the past 10 years, noxious weed occurrences have increased in the county as they have in much of Montana, due in part by the lack of general lack of interest or recognition of noxious weed seed impacts by the general population. The increased invasion of non-native species from high density areas can be attributed to: increased vehicle traffic on the bisecting highways, increased hunter activity on secondary roads and private roads, and increased reliance on out-of-county hay. These experiences mirror reports from many other locations in the Western United States.
In an effort to maintain the current low or non-existent noxious weed levels in Garfield County, the Weed Prevention Area (WPA) concept has been embraced. Large, contiguous acreages have been included in the WPA with many of the landowners working jointly to scout for new weed threats. The principle behind the concept is to limit new infestations by increasing the awareness of private landowners, hunters and other visitors to the detrimental impacts of noxious weeds to the environment. In addition to the awareness message, landowners are encouraged to routinely monitor their private and leased lands for new weed infestations and work aggressively to eradicate any noxious weeds they located. To assist the landowners in tracking the weed-free status of their lands, GPS technologies have been employed to map current weed locations and to verify locations and acreages of non-infested lands.

Project Objectives:

This project was designed to promote the following topics:
Outcome based education program
Early weed control methods
Provide tools to restrict weed spread
Protect weed free ecological state of the area
A minimum of 14 ranches will participate in the program

These topics will be provided by striving to meet the following objectives:
Delineate and protect weed free areas from invasive species.
Establish a Weed Prevention Area and educate ranches about the benefits of participation in a Weed Prevention Area.
This objective will be accomplished by:
Raising stakeholder awareness of early weed control, the tools available for early weed control that will restrict ecological and economic impacts through local level awareness and social marketing.
Delineating and prioritizing weed free areas for Weed Prevention Area participation.
Maintain a healthy weed free ecological state by implementing rancher designed Weed Prevention Areas with specific integrated prevention and management plans.

The components used in the process include:
Education and weed identification
Developing and implementing weed prevention strategies
Early weed detection and rapid response to infestations
Global positioning systems (GPS), monitoring and mapping


Click linked name(s) to expand/collapse or show everyone's info
  • Robert Cosgriff
  • Colin Murnion
  • Pohney Murnion


Materials and methods:

The Garfield County Weed Prevention Area project was designed as a landowner/producer driven group working toward a common goal. The group’s stated goal and objective is to, “protect rangeland and farmland’s productive capacity from invasive weeds to safeguard sustainable agricultural production of livestock, forage and small grains in Garfield County Montana.”
To meet these objectives, the following materials and methods were implemented in each respective area.
The WPA needed to be outlined and delineated. The groups choose to use as many road ways as possible when working on the boundaries. While delineation is useful, it should and will not be a stringent barrier. The participants feel/felt that anyone and everyone should be encouraged to participate because it makes for a stronger group and offers a greater area and number of people working to keep weeds from obtaining a foothold in the County.
A boundary was decided upon that included all of the active participants. The Boundary used both State Highways and County Roads as delineations, as well as ranch boundaries. The area encompasses approximately 250,000 acres of farm and ranch land with 25 active participants. The original area has been expanded to include several other ranches that wanted to participate. To fully recognize the additional ranches, the boundaries were extended, again using State highways and County roads as delineators.
New protocols were developed for monitoring noxious weeds while the mapping efforts were being conducted. Research has shown that most new weed infestations originate along high use areas and waterways, easy seed transmittal locations. The monitoring and mapping procedures call for identifying all moderate to high use roads, or those used by hunters in the fall, on the ranch and all the major coulees and actively flowing waterways. Efforts are then concentrated to the higher probability areas, and they are the locations targeted by the weed scout.
A weed scout’s job is to visually inspect each identified area and record progress with a hand held GPS unit. The data are later downloaded and transferred to mapping software where ranch and WPA maps are made identifying inspected areas and the locations of known weed infestations.
The weed scout visually inspects the high probability weed locations and any adjoining drainages. The weed scouting may be accomplished with a 4 wheeler, pickup, horseback, walking or any means seen fit to cover the area. A mobile GPS unit is used record the entire route or area surveyed. Any location where a listed noxious weed was recorded, a unique GPS waypoint is marked and the weed identified. The weed location data will later be downloaded and maps created to show the areas that were monitored. The data were then analyzed to determine the extent of weed infestations and, over several years, monitor and evaluate weed trends.

A survey was developed to measure the impacts of the educational components of the program. A pre and post project survey was conducted with the participants. The changes measured would reflect those outlined in the goals and objective of the project and included management and methods, weed identification and general noxious weed awareness.
Analysis of the survey was conducted using percentage change in the group’s responses from the beginning of the project in 2005 to the completion in the fall of 2008. Data will be analyzed and discussed in the results section.

Garfield County Weed Prevention Area

Ranch Name:_______________________________________________________

1. Does a State highway or County road bisect the ranch? YES NO
2. Where do you feel the majority of noxious weeds/weed
seeds in Garfield County have come from? ____________________________________________________________________________________________________________________________________________________________
3. How great a problem do you view noxious weed encroachment is to the sustainability of your ranch and farming operations? Please circle a value.
Not a problem Mild Problem Major Problem
1 2 3 4 5 6 7 8 9 10

4. Do you currently actively monitor for noxious weeds on your property? YES NO
5. Do you currently manage known noxious weeds with mechanical practices? YES NO
6. Do you currently manage known noxious weeds with herbicides? YES NO
7. Do you currently manage known noxious weeds with bio-control agents? YES NO
8. Do you currently map noxious weed locations? YES NO
If YES, How do you map? GPS FSA map Other________________________

9. Do you feel you can accurately identify the following noxious weeds?
1. Spotted knapweed YES NO 1 2 3 4 5
2. Russian knapweed YES NO 1 2 3 4 5
3. Canada thistle YES NO 1 2 3 4 5
4. Salt cedar YES NO 1 2 3 4 5
5. Leafy spurge YES NO 1 2 3 4 5
6. Yellow star thistle YES NO 1 2 3 4 5

10. What resources if any do you use to help identify weeds?___________________________
11. Are you currently using any weed prevention management strategies?________________

Cited Literature:

Californian Bereau of Land Management. 2003. Weed Management and Prevention Guidelines for Public Lands.
Sheley, Roger and Kim Goodwin. 2000. Plan Now for Noxious Weed Invasion. Montana State University.
Sheley, R., M. Manoukian and G. Marks. 2000. Preventing Noxious Weed Invasion. Rangelands. June 1996. 18(3):100-101.
Trainor, Meghan and A.J. Bussan. 2000. Integrated Weed Management; Preventing Weed Invasion. Montana State University Extension.
Siegel, Steven., Susan Donaldson. 2003. Measures to Prevent the Spread of Noxious and Invasive Weeds Durning Construction Activities. Fact Sheet-03-59. University of Nevada Cooperative Extension.
Sheley Roger L., Bret E. Olson, Carla Hoopes. 2005 (revised). Impacts of Noxious Weeds, What is so dangerous about the impacts of noxious weeds on Montana’s ecology and economy? Montana State University Extension Publications Bulletin No. 152. Montana State University Extension Service.

Research results and discussion:

28 ranches now have GPS units and have learned how to use them to monitor for noxious weed encroachment.
250,000 acres have been delineated as a Weed Prevention Area, within the area, 28 ranches have become active cooperators. The ranches strive to maintain the current weed free status of the area by following the guidelines and management plans that they developed.
8 large signs delineating the WPA and providing a weed prevention message have been located around and within the delineated WPA
Maps with 4 years of information have been developed that accurately show known weed locations and show areas that have been scouted/monitored by either the land owners or the weed scout. The maps also can be used to show the relative reduction in weed locations along the road ways since 2005.
A proactive WPA brochure with weed identification picture and the WPA goals was developed based on participants requests. The brochure will be used to raise awareness within the area and the rest of the County to noxious weeds and their negative impacts to the sustainability of Agriculture. Participants requested an easy to use brochure for distribution to hunters, fisherman, recreationalist, truck drivers and other persons entering the county.
Weed identification publications were distributed to all the WPA participants. The weed identification materials were requested to help participants quickly id weeds they discover while monitoring the area.
2 4x4 mounted commercial grade spray units were placed in the WPA for participants use. The spray units have been a great success and several ranches have purchased their own units following the use of the WPA units. These sprayers have allowed ranchers to quickly control weeds in hard to reach areas.

Participation Summary

Research Outcomes

No research outcomes

Information Products

Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.