The Yolo County Weed Management Area (YCWMA) was formed in 1999 by federal, state, county and city agencies, private industry, and landowners that are concerned about the explosion of invasive plant species in Yolo County.  The YCWMA promotes and coordinates efforts toward the management and control of the County’s noxious weeds through education and cooperation with landowner’s, agencies, and the general public.  If you are interested in weed control – please join us!  To read more information about our organization and goals you can link to our MOU document and our Strategic Plan.

The YCWMA uses an integrated approach in weed control and eradication.  Herbicides, hand removal, mechanical removal, mowing, burning, grazing, mulching, biological control, and revegetation are all methods employed to various extents on a project by project basis to achieve the most biologically sound, environmentally friendly, and cost effective, long-term weed control possible. 

Links:  California Department of Food and Agriculture weed webpages, and also refer to our Resource Library Weeds Section ( for individual weed information sheets), and our On-Farm Practices folder for a summary on weed control and a link to a more in-depth article titled Invasive Weed Control.

Project Site Examples

Sloughs and canals:  These waterways wind their way throughout much of the County.  They are a major means of transport for weeds in the county and between counties.  We will be conducting an inventory of weeds that occur along 2 specific sloughs in the Willow Slough Watershed.  From this initial inventory, a strategy will be developed infestations for reduction of weeds and revegetation while working with the adjacent landowners. For example, if infestations of giant reed are detected along the slough, a large map will be developed illustrating all the detected populations.  Incipient populations and populations at the top of the slough will be prioritized for removal.  Removal will be planned and conducted using hand-cutting and stump treatment with herbicide.  Follow up treatments would be planned for subsequent years along with revegetation using native species.

Roadsides:  Our roadside weed control program includes the initial use of herbicides with integrated methods being employed as funding becomes available.  County roads are treated with a non selective herbicide four times per year.  If the roadside contains perennial pepperweed, yellow starthistle, or other state listed noxious weeds, alternative chemicals like Transline and Telar are  used to more effectively treat these species.  The avoidance of using herbicides with soil residual activity allows the Yolo County RCD to revegetate some of these weedy roadside locations with native perennial grasses.  These sites may also undergo further weed control through the utilization of prescribed burning, mowing, and hand removal, while competitive natives become established.  Additional benefits of revegetating with native grasses include increased native plant diversity, soil stabilization, increased wildlife habitat, and improved water quality.  These roadside revegetation projects are often done with the cooperation and participation of local landowners.

Private landowners: The YCWMA works with landowners to encourage and find funding to support priority weed control efforts.  Each infestation is assessed along with the control options available, the sensitivity of natural resources in the area, and the preferences of the landowner.  Projects within the County include the use of herbicides, a combination of grazing and herbicides, grazing alone, mowing, mulching, burning, biological control, and revegetation.   

Techniques and Technologies

A new state-of-the-art spray rig:  This piece of equipment was recently purchased by the County Agricultural Commissioner's Office for roadside weed control.  This rig has many benefits to previously used spray equipment.  It allows more precise mixing, less waste material, more accurate spraying, decreased spray time, and the ability to switch herbicides in a moment to apply more appropriate herbicides for a more effective treatment. 

GPS/GIS (Geographical Information Systems) technology:  We were recently awarded funding for a Geo Explorer III unit.  This, used in combination with Arc View 3.2 GIS software, will provide us with excellent tools for map production, illustrating weed infestations, and efficient strategic planning of future weed control activities. 

State-of-the-art native grass seed drill by Truax Co.: This planter combines features of  the traditional seed drill used in agriculture with slight modifications that allow the irregular seed of native perennial grasses to be uniformly distributed, covered with soil, and lightly pressed into the seed bed.  This piece of equipment has and will continue to aide in our revegetation efforts at many locations where drill seeding is appropriate. 

The Yolo County Weed Management Area’s weed management strategy includes:

• Disseminating weed management and control information to the public, rural landowners, agencies, policy makers, and others;
• Conducting workshops that include weed identification and management techniques;
• Mapping infestation areas for specified weeds in Yolo County;
• Reducing transport of seeds or other plant parts capable of reproduction;
• Improving coordination and cooperation between all agencies involved with noxious and invasive weeds in Yolo County;
• Providing an infrastructure and facilitate research programs for weed management and eradication programs within the county;
• Promoting changes in land treatment that result in a reduction of weeds of concern to the YCWMA including revegetation and restoration. 

Revegetation

The YCWMA promotes and conducts the control of noxious weeds and supplemental restoration with non- weedy, competitive native species in many of its project locations.

Projects

Past projects (2000-2002)

• Yellow starthistle and puncturevine control and native perennial grass revegetation along the Davis Bike Path;
• Yellow starthistle control along a 5 mile stretch of I-505 including adjacent landowner participation and native perennial grass revegetation;
• County Agricultural Commissioner’s office expansion of A and B rated noxious weed control in Yolo County. (CDFA noxious weed web page)
• Cost share program with private landowners, agencies, and environmental groups;
• Putah Creek Council and Lower Putah Creek Coordinating Committee perennial pepperweed eradication project;
• Cache Creek Conservancy yellow starthistle eradication project;
• YCWMA project and noxious weed mapping project.

Past & proposed projects (2002-2004)

• Perennial pepperweed eradication/control at Yolo Grasslands Regional Park.
• Perennial pepperweed control along highway 113 from County Road 24 to County Road 29.
• Spraying of County roadsides targeting perennial pepperweed, yellow starthistle, puncturevine, Russian Thistle, and Johnson grass, with the goal of replacing County grading and mowing, to reduce weed spread. 
• Developing a Weed Management Area Display Booth;
• Organizing an Weed Management Area Weed Tour;
• Continue to fund a Weed Warrior to help coordinate and implement projects and acquire funding;
• Continue and expand the already existing Davis Bike Path weed control and restoration project, the  I-505 yellow starthistle control program, the A & B rated weed control conducted by the County Agricultural Commissioner, and the cost share program;
• A Chickahominy Slough Weed Inventory and Demonstrations Project;
• Cal Trans perennial pepperweed control, expanding the project from just along a portion of Highway 113 to all other state highways in Yolo County;
• California Northern Railroad Weed Control Expansion Project – expanding traditional weed control along railroad rights-of-way 30 ft on either side of the railroad berm;
• Small landowner’s Cooperative Weed Control which will use integrated weed management techniques including burning, hand pulling, and chemicals to control weeds such as yellow starthistle and medusahead on private land in a 160 acre section;
• Traditional Methods of Managing Non-natives at the Cache Creek Conservancy mainly using burning, coppicing, pruning, mowing, tilling, and weed whipping to promotes native plants and conduct weed control within a tending and gathering garden.

Partners

Yolo County Agricultural Commissioner, City of Woodland, City of Davis, Yolo County Farm Bureau, Yolo County Department of Public Works, Cal-Trans, Yolo County Flood Control, County Parks, California Department of Forestry, Reclamation Districts, Yolo Shortline, California Northern Railroad, local Fire Districts, Yolo County, Cattleman and Woolgrowers, California Native Plant Society, Cache Creek Conservancy, California Department of Water Resources, California Department of Fish and Game, Natural Resources Conservation Service (NRCS), Yolo Basin Foundation, University of California at Davis, Community Alliance with Family Farmers, Environmental Education Farm Foundation.

For more information contact the Yolo County Resource Conservation District at (530) 662-2037 ext. 114 or the Yolo County Agricultural Commissioner at (530) 666-8140.