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Noxious weeds

King County, Washington

To offer a suggestion or report an error on the King County Noxious Weeds website, please contact Sasha Shaw, education specialist.

KC Weed News - April 2006

Goatsrue flowersTopics Below

Weed of the Month: Goatsrue, Class A Noxious Weed

Goatsrue in a field with Steve BurkeThe story behind this noxious weed is sadly ironic. First introduced from the Middle East to Utah in 1891 as a possible forage plant, it soon became evident that it contained a poisonous alkaloid making it toxic to livestock (thus the name goat’s rue!). Fortunately for the animals being fed with this plant, it is also bitter and they generally avoid it. Unfortunately for us all, goatsrue had already spread before this was realized and it eventually infested 60 square miles around the original area of introduction. When efforts began to control this plant, it soon became evident that it would be no easy matter due to the massive root crowns and prolific seed production. Utah first listed this plant as a noxious weed in 1974 followed by federal listing by USDA/APHIS in 1981. The eradication project began in 1976 in Utah continues to this day as new plants show up every year from the seed bank and established populations stubbornly resist control efforts.

Smaller infestations of goatsrue have popped up in other states over the last few decades and, as luck would have it, several fairly large populations were discovered in the Federal Way area in 1999. Following official listing on the Washington State Noxious Weed List, the King County Noxious Weed Program developed an action plan for eradicating these populations and for detecting small, pioneering populations elsewhere in the county. Since 2000, we have discovered 17 different infestations on parcels and 13 roadside populations. In 2005, the total goatsrue population size for the county was approximately 2.5 acres, although the area impacted is much higher. Although we have made progress on containing the spread of this plant, there is still a lot of work to do. We are confident that we can work towards eradication of this noxious weed from the county by combining the resources and efforts of private property owners, the City of Federal Way, our own program, and outside funding including a small grant from the National Fish and Wildlife Foundation.

Goatsrue can succeed in a wide range of habitats and conditions although it prefers full sun. It tolerates acid soil and seasonally wet areas, often spreading along waterways and in wet pastures. In King County, it is found in undeveloped vacant sites that are seasonally wet, historic pasture sites, and along fence lines and road right of ways. It shares habitat with grass, blackberries, shrub roses, Scotch broom, and Canada thistle. Goatsrue can form a monoculture in wetland ecosystems and displace native vegetation and wildlife.

Goatsrue emerges in late April and can be more easily identified in May or June when it flowers. It is in the pea family and looks somewhat like a bushy vetch with pale purple to white flowers. Because this plant is somewhat difficult to identify and resembles many other plants, it is important to get a definite identification before taking action. Because of the potential damage that goatsrue could do and its very limited distribution, we place a high priority on early detection and eradication of this plant.

Please contact the King County Noxious Weed Program if you spot any goatsrue in the county by calling us at 206-296-0290 or emailing us at You can also report an infestation using our online report form.

Meet the Weed Crew

The 2006 weed season has begun and the King County Noxious Weed Program is fully staffed once again. Our seasonal regional weed specialists are already heading out to the field to track down high priority Class A and B noxious weeds and to work with landowners and property managers to get these problem plants controlled. Each specialist is assigned a region of the county that includes both incorporated and unincorporated areas. Our program is very fortunate to have a crew of highly motivated weed specialists who enjoy talking to people and helping them to find answers to their noxious weed problems. If you would like to meet your regional weed specialist, please do not hesitate to call our program at 206-296-0290 or send them an email at

  1. Karen Peterson : North Seattle, Shoreline, Lake Forest Park, Kenmore, Bothell, Woodinville
  2. Frances Lucero : Kirkland, Redmond, Sammamish, Carnation, Duvall, Skykomish
  3. Monica Walker : Central and East Seattle, Mercer Island, Knotweed Project Manager
  4. Maria Winkler : West Seattle and Harbor Island, Vashon Island
  5. Amy Yahnke : Tukwila, Burien, SeaTac, Normandy Park, Des Moines, Federal Way, western Kent
  6. Sarah Baker : Bellevue, Newcastle, Medina, Hunts Point, Yarrow Point, Clyde Hill, Renton, Snoqualmie, North Bend
  7. Dennis Chambreau : eastern Kent, Covington, Maple Valley, Black Diamond
  8. Trish MacLaren : Auburn, Milton, Algona, Pacific, Enumclaw

We also have three weed specialists who work year round throughout the county. They can be reached at our program line 206-296-0290 or directly by email:

And finally, for information on the Weed Board, program business, educational activities or general weed questions, please contact:

Permit Update for Aquatic Weed Control

If you are confused about what state permit you need for controlling aquatic weeds, you’re not alone! Hopefully this brief summary will help make it clearer. As of March 1, the Department of Ecology is now issuing the new Aquatic Plant Control Permit for both private and public projects. This permit is required when pesticides will be applied in water to control submersed and floating noxious weeds, nuisance plants and algae. This applies to both private and public pesticide applicators and the permit is obtained by the applicator themselves, not by a sponsoring agency or organization. This permit is not required for emergent plants such as purple loosestrife or yellow flag iris, however it can cover control of emergents as part of a lake-wide project if the project also includes submersed or floating plants such as milfoil or water lily. (Aquatic Pesticide Permits).

For the use of herbicides to control emergent noxious weeds growing adjacent to water, WSDA will still generally offer coverage under its NPDES permit through the convenient, stream-lined web-based application process. This is the coverage you would usually need for purple loosestrife, knotweed along riverbanks and other shoreline and wetland weeds. Just like last year, public agencies can obtain coverage for a larger project that can cover other applicators. In all cases, of course, a licensed applicator with the aquatic endorsement needs to be applying the herbicide or directly supervising the applicators in the field. (NPDES Permit for Aquatic Noxious Weed Control)

For more information on how the proposed changes will affect aquatic noxious weed control projects in King County, please call Katie Messick or Steve Burke at 206-296-0290.

Green Seattle Partnership: A Model Invasive Species Approach

According to an analysis done by the City of Seattle’s Urban Forest Program and the Cascade Land Conservancy, Seattle is at risk of losing more than 70 percent of its forest canopy in the next 20 years due to old age and competition with aggressive invasive plants such as English ivy, and Himalayan blackberry. A little more than a year ago, the Cascade Land Conservancy and the City of Seattle entered into the Green Seattle Partnership, a program to restore 2500 acres of Seattle’s forested parklands in 20 years.

Perhaps one of the most innovative aspects of this partnership is the long term, strategic, landscape-scale approach it is taking. Invasive plants in any habitat often require just this kind of approach and commitment over the long term. Traditionally most projects have been planned for three to five years at best, but the Green Seattle Partnership has been developed with the next 20 years in mind. There are many other creative elements to the plan including prioritizing properties, placing resources where they can be most effective, and providing assistance and support to existing community stewards so they can be even more effective and strategic in their efforts. Seattle is not alone in our region in having so much forest land at risk. Other cities have begun similar undertakings and will be facing many of the same challenges and issues as Seattle. The model of a private-public partnership and strategic, long-term planning is one that could be highly effective for many cities in our region. We will be watching the progress of the Green Seattle Partnership closely and encouraging their progress in any way we can.

WNPS Presents: Freshwater Invasive Weeds by Kathy Hamel, WA DOE

Freshwater invaders such as Eurasian watermilfoil--the bane of boaters, purple loosestrife--the escaped ornamental, and the incredibly destructive hydrilla cause multimillions of dollars of damage every year in Washington. For more than twenty years, Kathy has been working to control these and the many other exotic and invasive species found in our freshwaters. She'll describe how they got here, the damage they do, and what is being done to limit their spread and impact. The Washington Native Plant Society is hosting this presentation at Center for Urban Horticulture, University of Washington Campus, 3501 NE 41st St., Seattle on Thursday, April 6, 7:00-9:00 pm. For more information contact Howard Coleman, (206) 633-4195,

Weed Program Events on Earth Day – April 22

  • Shoreline Natural Yard Care Fair, Central Market, 155th & Aurora, 9-3
  • Duwamish Alive – Earth Day 2006, People for Puget Sound, Herrings House Park

Noxious Weed Workshops for Weed Crews

The noxious weed program will once again offer two May workshops for vegetation management crews and others who need to identify and manage noxious weeds as part of their work. Using live specimens and slides, we will focus on how to identify and control noxious weeds that are designated for control in King County. Topics include: upland and riparian noxious weed ID and control, aquatic noxious weed ID, control and permits, and biocontrol options for western Washington.

  • North King County Class: May 3, 8:30-11:30am, Kenmore
  • South King County Class: May 10, 8:30-11:30am, Kent

To register please contact Sasha Shaw at 206-263-6468 or Please feel free to pass this information on to others who may be interested as well. Both classes are free and open to the public. WSDA pesticide license recertification credits will be available for both classes.

Washington State Weed Board’s May 16 Noxious Weed Tour in Seattle

Noxious weeds pose serious threats to urban resources. This noxious weed tour, co-hosted by the Washington State Weed Board, the King County Weed Board and the Center for Urban Horticulture, will highlight the impact of noxious weeds on urban forests, public health, recreation and natural areas. In addition, this tour will demonstrate the importance and effectiveness of early detection and eradication of newly invading species. Project managers will guide us through two urban natural areas seriously impacted by a wide variety of invasive species and describe the long term efforts underway to restore the ecological and recreational functions of these areas. The tools being used to manage invasive species include a wide range of options including biocontrol and volunteer stewardship. The tour will also include pioneering infestations of Class A noxious weeds giant hogweed and garlic mustard, monitor species that are being evaluated for possible noxious weed listing in Washington, and an infestation of garden loosestrife, a tough wetland weed that may well overtake purple loosestrife in its impact on wetlands and shoreline habitat. The tour is on May 16, 1:00pm-4:30pm followed by the State Weed Board meeting on May 17. Buses will start and end at the Center for Urban Horticulture, 3501 NE 41st Street, Seattle, WA 98105. To register or for more information, please contact Steve McGonigal, 360-902-2053 or or Steve Burke, 206-205-6927,

Mid Fork Snoqualmie Invasive Plant Workshop and Field Trip

Volunteers led by the Mountains to Sound Greenway and Cascade Land Conservancy are engaged in a multi-year effort to rid the spectacular Middle Fork Snoqualmie River Valley of invasive weeds. If you’d like to learn more about invasive plants, especially those found in the Middle Fork, please join this class. Experts from the King County Noxious Weed Control Program will lead a classroom session using live specimens and slides, followed by several hours of field identification in the Middle Fork Valley. We will meet at the Ranger Station in North Bend for a slide show presentation and then head to the field. Workshop is May 20 from 9am to 2pm, starting and ending at the US Forest Service North Bend Ranger Station. Bring a lunch and dress for the weather. The class is free and open to the public, but please sign up by emailing Kelly Kirkland or calling 206-812-0122. For more info call Sasha Shaw at 206-263-6468.

Knotweed Control Workshop and Demonstration

Tackling knotweed can be a daunting task but the benefits are truly rewarding. Our program will be holding a hands-on training on knotweed control that will include how to use different methods, where they work best, and how to develop a coordinated knotweed management plan to improve your chances for success. We will be demonstrating control methods on live knotweed. This workshop is being hosted by Dave Olson, a homeowner on the beautiful South Fork Snoqualmie River who is working toward his vision of a knotweed-free river. For more information or to register, contact Sasha Shaw, 206-263-6468, The workshop is June 1, 6:30-8:00pm and it is free and open to the public.

Pasture Weed Workshops

Troubled by weeds? Come to one of our pasture weed workshops this June to learn how to identify and manage troublesome weeds coming up in fields, forests and fencelines. The workshop will provide information on plants that damage pasture quality and livestock health and how to manage weeds in pastures. Bring your weeds to show and tell and bring your questions to “stump a weed expert”. To register, please contact Sasha Shaw at 206-263-6468 or

Dates, Times and Locations:

  • June 8, 7 pm, Snoqualmie’s Meadowbrook Farm
  • June 13, 7 pm, Covington Library
  • June 14, 7 pm, Auburn Library
  • June 20, 7 pm, Enumclaw Library
  • June 27, 7 pm, Vashon Land Trust

Community Stewardship Grants from King County

  • WATERWORKS Grants up to $50,000 are available for on-the-ground water quality or water-related habitat projects ranging from demonstration green roofs to salmon stream restoration. Projects must be in the King County Water Treatment Division service area.
  • RURAL COMMUNITY PARTNERSHIP grants up to $15,000 are available for similar projects located outside the Urban Growth Boundary
  • WILD PLACES IN CITY SPACES grants up to $10,000 are available for the restoration of upland habitat or urban forestry within the Urban Growth Area

The deadline for proposals over $2,500 is May 1, 2006. There are no deadlines for proposals up to $2,500. Note that units of King County government cannot apply, however King County can be a project partner. For more information and the applications, please consult the grant exchange web page: Grant Exchange

Youth in Forestry Grants from Natural Resource Stewardship Network

The Natural Resource Stewardship Network offers grants and technical assistance to projects that involve after school activities related to forests. Projects must be located in King County; enhance forests or forested habitat; and empower citizens to protect, conserve or manage trees and/or forested areas. The maximum grant award is $20,000. Technical assistance means that an expert from one of the member organizations may volunteer time on your project. May 15, 2006 is the next deadline for grants over $2,500. Apply for small grants or technical assistance any time. To learn more or to download a Guidelines and Application packet, visit our website at Natural Resource Stewardship Network or contact Linda Vane by voice at (206) 296-8042, TTY 711 or by email at The Natural Resource Stewardship Network is a collaboration of government agencies, educational institutions and volunteers. its Technical Assistance Group includes: Washington Department of Natural Resources, King County Water and Land Resources Division, Washington State University Extension, King Conservation District and individual volunteers.