Invasive Forest Weeds Resources
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Four Key Resources:
- King County Noxious Weeds Identification Photos – A great source of identification photos, information, and best managment practices
- Pacific Northwest Handbooks: Weed Managment Handbook – Noxious weed information on specific species, with treatment options, from OSU, WSU, and U of I
- Spokane County Noxious Weed List – A collection of fact sheets on invasive species
- Whatcom County Noxious Weed Fact Sheets – An extensive list of fact sheets on invasive species and management options
Topic List
- Absinth wormwood
- Butterfly bush
- Common St. Johnswort
- Common Tansy
- English ivy
- English hawthorn
- English holly
- European mountain-ash
- Garlic mustard
- Giant hogweed
- Gorse
- Hawkweeds, orange and yellow
- Herb-Robert
- Himalayan and evergreen (cut-leaf) blackberry
- Houndstongue
- Knapweeds, spotted, diffuse, and meadow
- Knotweeds
- Old man’s beard
- Oxeye daisy
- Poison-hemlock
- Reed canarygrass
- Scotch, French, Spanish, and Portuguese brooms
- Spurge laurel
- Sulfur cinquefoil
- Tansy ragwort
- Thistles, Canada, bull and musk
- Yellow archangel
- Yellow toadflax
Notes:
- Many of the publications and documents on this page are PDF files – Get Adobe Reader.
- Some WSU Extension web sites provide links to external sites for the convenience of users. These external sites are not managed by the WSU Extension. Furthermore, WSU Extension does not review, control or take responsibility for the content of these sites, nor do these sites implicitly or explicitly represent official positions and policies of WSU Extension.
General noxious weed resources
- Invasive Weeds Of Eastern Washington (PDF) – WSU Extension Manual EM005
- King County Noxious Weeds Identification Photos – A great source of identification photos and information
- Nonnative Invasive Plants of Pacific Coast Forests – A Field Guide for Identification (PDF) – USFS PNW-GTR-817
- Noxious Weeds: Everyone’s Enemy (YouTube) – A 50-minute informational video from WSU Extension on noxious weed identification and control
- Pacific Northwest Handbooks: Weed Managment Handbook – Noxious weed information on specific species, with treatment options, from OSU, WSU, and U of I
- Rights-of-Way Vegetation Management – WSU Extension Publication MISC0185
- Spokane County Noxious Weed List – An extensive list of fact sheets on invasive species
- Washington State Noxious Weed Control Board – Extensive information on the Washington State noxious weed list, relevant laws, and resources
- Whatcom County Noxious Weed Fact Sheets – An extensive list of fact sheets on invasive species and management options
- WSU Extension Weed Identification Service – Send in a sample or a photo and have your weed identified!
State and county noxious weed agencies
- Washington State Invasive Species Council
- Washington State Noxious Weed Control Board
- Adams County Noxious Weed Control Board
- Asotin County Noxious Weed Control Board
- Benton County Noxious Weed Control Board
- Chelan County Noxious Weed Control Board
- Clallam County Noxious Weed Control Board
- Clark County Noxious Weed Control Board
- Columbia County Noxious Weed Control Board
- Cowlitz County Noxious Weed Control Board
- Douglas County Weed Management Task Force
- Ferry County Noxious Weed Control Board
- Franklin County Noxious Weed Control Board
- Garfield County Noxious Weed Control Board
- Grant County Noxious Weed Control Board
- Grays Harbor County Noxious Weed Control Board
- Island County Noxious Weed Control Board
- Jefferson County Noxious Weed Control Board
- King County Noxious Weed Control Board
- Kitsap County Noxious Weed Control Board
- Kittitas County Noxious Weed Control Board
- Klickitat County Noxious Weed Control Board
- Lewis County Noxious Weed Control Board
- Lincoln County Noxious Weed Control Board
- Mason County Noxious Weed Control Board
- Okanogan County Noxious Weed Control Board
- Pacific County Noxious Weed Control Board
- Pend Orielle County Noxious Weed Control Board
- Pierce County Noxious Weed Control Board
- San Juan County Noxious Weed Control Board
- Skagit County Noxious Weed Control Board
- Skamania County Noxious Weed Control Board
- Snohomish County Noxious Weed Control Board
- Spokane County Noxious Weed Control Board
- Stevens County Noxious Weed Control Board
- Thurston County Noxious Weed Control Board
- Wahkiakum County Noxious Weed Control Board
- Walla Walla County Noxious Weed Control Board
- Whatcom County Noxious Weed Control Board
- Whitman County Noxious Weed Control Board
- Yakima County Noxious Weed Control Board
Aquatic weed general resources
- Water Weeds: Guide to Aquatic Weeds in King County – King County Noxious Weed Program
- Auquatic Weed Idenification Flowchart (PDF) – King County Noxious Weed Program
- Aquatic Vegetation Management and Control – PNW Extension Manual PNW224
- Water Weeds: Guide to Aquatic Weeds in King County (PDF) – King County Noxious Weed Program Pamphlet
The worst forest offenders: A selection of resources
Absinth wormwood (Artemisia absinthium)
- Absinth wormwood identification and control – King County Noxious Weed information
- Absinth wormwood – WA State Noxious Weed Control Board information
Butterfly bush (Buddleja davidii)
- Butterfly Bush (PDF) – Whatcom County Noxious Weed Fact Sheet
- Invasive Weeds in Forestland: Butterfly Bush (PDF) – OSU Extension Bulletin EC1589
- Butterfly bush identification and control – King County Noxious Weed information
- Butterfly Bush – WSU Extension Bulletin EB2007E
- Control Options for Butterfly Bush (PDF) – Whatcom County Noxious Weed Fact Sheet
Common St. Johnswort (Hypericum perforatum)
- St. Johnswort (PDF) – Whatcom County Noxious Weed Fact Sheet
- Control options for St. Johnswort (PDF) – Whatcom County Noxious Weed Fact Sheet
- Common St. Johnswort identification and control – King County Noxious Weed information
- Common St. Johnswort – WA State Noxious Weed Control Board information
Common tansy (Tanacetum vulgare)
- Common tansy (PDF) – Whatcom County Noxious Weed Fact Sheet
- Control options for common tansy (PDF) – Whatcom County Noxious Weed Fact Sheet
- Common tansy identification and control – King County Noxious Weed information
- Common tansy – WA State Noxious Weed Control Board information
English hawthorn (Crataegus monogyna)
- English Hawthorn(PDF) – Whatcom County Noxious Weed Fact Sheet
- English hawthorn identification and control – King County Noxious Weed information
English holly (Ilex aquifolium)
- Best Management practices for English Holly (PDF) – publication from Metro Vancouver and the Invasive Species Council of Metro Vancouver.
- English Holly (PDF) – Whatcom County Noxious Weed Fact Sheet
- Control Options for English Holly(PDF) – Whatcom County Noxious Weed Fact Sheet
- English holly identification and control – King County Noxious Weed information
English ivy (Hedera helix)
- English Ivy (PDF) – Whatcom County Noxious Weed Fact Sheet
- Control options for English ivy (PDF) – Whatcom County Noxious Weed Fact Sheet
- Invasive Weeds in Forestland: English Ivy (PDF) – OSU Extension Bulletin EC1595
- English ivy identification and control – King County Noxious Weed information
European mountain-ash (Sorbus aucuparia)
- European mountain-ash identification and control – King County Noxious Weed information
- European Mountain Ash – Washington State Noxious Weed Control Board
- European mountain-ash identification and control – King County Noxious Weed information
- European Mountain Ash – Washington State Noxious Weed Control Board
Garlic mustard (Alliaria petiolata)
- Garlic Mustard (PDF) – Whatcom County Noxious Weed Fact Sheet
- Invasive Weeds in Forestland: Garlic Mustard (PDF) – OSU Extension Bulletin EC1592
- Garlic mustard identification and control – King County Noxious Weed information
- Garlic Mustard (PDF) – Whatcom County Noxious Weed Fact Sheet
- Invasive Weeds in Forestland: Garlic Mustard (PDF) – OSU Extension Bulletin EC1592
- Garlic mustard identification and control – King County Noxious Weed information
Giant hogweed (Heracleum mantegazzianum)…Dangerous!
- Giant Hogweed (PDF) – Whatcom County Noxious Weed Fact Sheet
- Giant Hogweed – Ohio State University Extension Bulletin ANR-35
- Giant hogweed identification and control – King County Noxious Weed information
- Control Options for Giant Hogweed (PDF) – Whatcom County Noxious Weed Fact Sheet
- Giant Hogweed (PDF) – Whatcom County Noxious Weed Fact Sheet
- Giant Hogweed – Ohio State University Extension Bulletin ANR-35
- Giant hogweed identification and control – King County Noxious Weed information
- Control Options for Giant Hogweed (PDF) – Whatcom County Noxious Weed Fact Sheet
Gorse (Ulex europaeus)
- Invasive Weeds in Forestland: Gorse (PDF) – OSU Extension Bulletin EC1593
- Gorse identification and control – King County Noxious Weed information
- Invasive Weeds in Forestland: Gorse (PDF) – OSU Extension Bulletin EC1593
- Gorse identification and control – King County Noxious Weed information
Hawkweeds, orange and yellow (Hieracium aurantiacum and Hieracium caespitosum)
- Orange hawkweed – Washingon State Noxious Weed Control Board
- Orange hawkweed (PDF) – Clallam County noxious weed alert
- Orange hawkweed identification and control – King County Noxious Weed information
- Yellow hawkweed identification and control – King County Noxious Weed information
- Orange hawkweed – Washingon State Noxious Weed Control Board
- Orange hawkweed (PDF) – Clallam County noxious weed alert
- Orange hawkweed identification and control – King County Noxious Weed information
- Yellow hawkweed identification and control – King County Noxious Weed information
Herb-Robert (Geranium robertianum)
- Herb-Robert (PDF) – Whatcom County Noxious Weed Fact Sheet
- Herb-Robert identification and control – King County Noxious Weed information
- Control options for Herb-Robert (PDF) – Whatcom County Noxious Weed Fact Sheet
- Herb-Robert (PDF) – Whatcom County Noxious Weed Fact Sheet
- Herb-Robert identification and control – King County Noxious Weed information
- Control options for Herb-Robert (PDF) – Whatcom County Noxious Weed Fact Sheet
Himalayan and evergreen (cut-leaf) blackberry (Rubus armeniacus and Rubus laciniatus)
- Blackberry (PDF) – Whatcom County Noxious Weed Fact Sheet
- Invasive Weeds in Forestland: Himalayan Blackberry and Evergreen Blackberry (PDF) – OSU Extension Bulletin EC1594
- Himalayan blackberry identification and control – King County Noxious Weed information
- Control Options for Himalayan Blackberry (PDF) – Whatcom County Noxious Weed Fact Sheet
- Blackberry (PDF) – Whatcom County Noxious Weed Fact Sheet
- Invasive Weeds in Forestland: Himalayan Blackberry and Evergreen Blackberry (PDF) – OSU Extension Bulletin EC1594
- Himalayan blackberry identification and control – King County Noxious Weed information
- Control Options for Himalayan Blackberry (PDF) – Whatcom County Noxious Weed Fact Sheet
Houndstongue (Cynoglossum officinale)
- Houndstongue identification and control – King County Noxious Weed information
- Houndstongue – WA State Noxious Weed Control Board information
- Houndstongue (PDF) – Lincoln County Noxious Weed Fact Sheet
- Houndstongue identification and control – King County Noxious Weed information
- Houndstongue – WA State Noxious Weed Control Board information
- Houndstongue (PDF) – Lincoln County Noxious Weed Fact Sheet
Knapweeds, spotted, diffuse, and meadow (Centaurea stoebe, Centaurea diffusa, and Centaurea jacea x nigra)
- Spotted Knapweed (PDF) – Whatcom County Noxious Weed Fact Sheet
- Spotted knapweed identification and control – King County Noxious Weed information
- Spotted Knapweed – WA State Noxious Weed Control Board information page
- SPOTTED KNAPWEED (PDF) – Clallam County Noxious Weeds fact sheet
- Diffuse knapweed identification and control – King County Noxious Weed information
- Diffuse Knapweed – WA State Noxious Weed Control Board information page
- Meadow Knapweed (PDF) – Whatcom County Noxious Weed Fact Sheet
- Meadow knapweed identification and control – King County Noxious Weed information
- Meadow Knapweed – WA State Noxious Weed Control Board information page
- Control Options for Knapweeds (PDF) – Whatcom County Noxious Weed Fact Sheet
- Spotted Knapweed (PDF) – Whatcom County Noxious Weed Fact Sheet
- Spotted knapweed identification and control – King County Noxious Weed information
- Spotted Knapweed – WA State Noxious Weed Control Board information page
- SPOTTED KNAPWEED (PDF) – Clallam County Noxious Weeds fact sheet
- Diffuse knapweed identification and control – King County Noxious Weed information
- Diffuse Knapweed – WA State Noxious Weed Control Board information page
- Meadow Knapweed (PDF) – Whatcom County Noxious Weed Fact Sheet
- Meadow knapweed identification and control – King County Noxious Weed information
- Meadow Knapweed – WA State Noxious Weed Control Board information page
- Control Options for Knapweeds (PDF) – Whatcom County Noxious Weed Fact Sheet
Knotweeds (Polygonum sachalinense, P. cuspidatum, and P. x bohemicum)
- Knotweeds (PDF) – Whatcom County Noxious Weed Fact Sheet
- Invasive Weeds in Forestland: Knotweeds (PDF) – OSU Extension Bulletin EC1597
- Invasive knotweed identification and control – King County Noxious Weed information
- Knotweed Shrubs: Identification, Biology, and Management (PDF) – PNW Extension Publication PNW610
- Control Options for Knotweeds (PDF) – Whatcom County Noxious Weed Fact Sheet
- Knotweeds (PDF) – Whatcom County Noxious Weed Fact Sheet
- Invasive Weeds in Forestland: Knotweeds (PDF) – OSU Extension Bulletin EC1597
- Invasive knotweed identification and control – King County Noxious Weed information
- Knotweed Shrubs: Identification, Biology, and Management (PDF) – PNW Extension Publication PNW610
- Control Options for Knotweeds (PDF) – Whatcom County Noxious Weed Fact Sheet
Old man’s beard (Clematis vitalba)
- Old man’s beard (PDF) – Whatcom County Noxious Weed Fact Sheet
- Old man’s beard identification and control – King County Noxious Weed information
- Control Options for old man’s beard (PDF) – Whatcom County Noxious Weed Fact Sheet
- Old man’s beard (PDF) – Whatcom County Noxious Weed Fact Sheet
- Old man’s beard identification and control – King County Noxious Weed information
- Control Options for old man’s beard (PDF) – Whatcom County Noxious Weed Fact Sheet
Oxeye daisy (Linaria vulgaris)
- Oxeye Daisy identification and control – King County Noxious Weed information
- Oxeye Daisy – WA State Noxious Weed Control Board information
- Oxeye Daisy identification and control – King County Noxious Weed information
- Oxeye Daisy – WA State Noxious Weed Control Board information
Poison-hemlock (Conium maculatum)
- Poison-Hemlock (PDF) – Whatcom County Noxious Weed Fact Sheet
- Poison-hemlock identification and control – King County Noxious Weed information
- Poison Hemlock – WA State Noxious Weed Control Board information
- Control Options for Poison-Hemlock (PDF) – Whatcom County Noxious Weed Fact Sheet
- Poison-Hemlock (PDF) – Whatcom County Noxious Weed Fact Sheet
- Poison-hemlock identification and control – King County Noxious Weed information
- Poison Hemlock – WA State Noxious Weed Control Board information
- Control Options for Poison-Hemlock (PDF) – Whatcom County Noxious Weed Fact Sheet
Reed canarygrass (Phalaris arundinacea)
- Reed Canarygrass (PDF) – Whatcom County Noxious Weed Fact Sheet
- Reed canarygrass identification and control – King County Noxious Weed information
- Control options for Reed Canarygrass (PDF) – Whatcom County Noxious Weed Fact Sheet
- Reed Canarygrass (PDF) – Whatcom County Noxious Weed Fact Sheet
- Reed canarygrass identification and control – King County Noxious Weed information
- Control options for Reed Canarygrass (PDF) – Whatcom County Noxious Weed Fact Sheet
Scotch, French, Spanish, and Portuguese brooms (Cytisus scoparius, Genista monspessulana, Spartium junceum, and Cytisus striatus)
- Scotch Broom (PDF) – Whatcom County Noxious Weed Fact Sheet
- Invasive Weeds in Forestland: Brooms (PDF) – OSU Extension Bulletin EC1598
- French broom identification and control – King County Noxious Weed information
- Scotch broom identification and control – King County Noxious Weed information
- Spanish broom identification and control – King County Noxious Weed information
- Control Options for Scotch Broom (PDF) – Whatcom County Noxious Weed Fact Sheet
- Scotch Broom (PDF) – Whatcom County Noxious Weed Fact Sheet
- Invasive Weeds in Forestland: Brooms (PDF) – OSU Extension Bulletin EC1598
- French broom identification and control – King County Noxious Weed information
- Scotch broom identification and control – King County Noxious Weed information
- Spanish broom identification and control – King County Noxious Weed information
- Control Options for Scotch Broom (PDF) – Whatcom County Noxious Weed Fact Sheet
Spurge laurel (Daphne laureola)
- Spurge Laurel (PDF) – Whatcom County Noxious Weed Fact Sheet
- Spurge laurel identification and control – King County Noxious Weed information
- Control Options for Spurge Laurel (PDF) – Whatcom County Noxious Weed Fact Sheet
- Spurge Laurel (PDF) – Whatcom County Noxious Weed Fact Sheet
- Spurge laurel identification and control – King County Noxious Weed information
- Control Options for Spurge Laurel (PDF) – Whatcom County Noxious Weed Fact Sheet
Sulfur cinquefoil (Potentilla recta)
- Sulfur cinquefoil (PDF) – Whatcom County Noxious Weed Fact Sheet
- Sulfur cinquefoil identification and control – King County Noxious Weed information
- Sulfur cinquefoil – WA State Noxious Weed Control Board information
- Control Options for Sulfur cinquefoil(PDF) – Whatcom County Noxious Weed Fact Sheet
- Sulfur cinquefoil (PDF) – Whatcom County Noxious Weed Fact Sheet
- Sulfur cinquefoil identification and control – King County Noxious Weed information
- Sulfur cinquefoil – WA State Noxious Weed Control Board information
- Control Options for Sulfur cinquefoil(PDF) – Whatcom County Noxious Weed Fact Sheet
Tansy ragwort (Jacobaea vulgaris)
- Tansy Ragwort(PDF) – Whatcom County Noxious Weed Fact Sheet
- Invasive Weeds in Forestland: Tansy ragwort (PDF) – OSU Extension Bulletin EC1599
- Tansy ragwort identification and control – King County Noxious Weed information
- Control options for Tansy Ragwort (PDF) – Whatcom County Noxious Weed Fact Sheet
- Tansy Ragwort(PDF) – Whatcom County Noxious Weed Fact Sheet
- Invasive Weeds in Forestland: Tansy ragwort (PDF) – OSU Extension Bulletin EC1599
- Tansy ragwort identification and control – King County Noxious Weed information
- Control options for Tansy Ragwort (PDF) – Whatcom County Noxious Weed Fact Sheet
Thistles, Canada, bull, and musk (Cirsium arvense, Cirsium vulgare, and Carduus nutans)
- Bull Thistle (PDF) – Whatcom County Noxious Weed Fact Sheet
- Bull thistle identification and control – King County Noxious Weed information
- Invasive Weeds in Forestland: Bull Thistle (PDF) – OSU Extension Bulletin EC1588
- Canada Thistle (PDF) – Whatcom County Noxious Weed Fact Sheet
- Canada thistle identification and control – King County Noxious Weed information
- Invasive Weeds in Forestland: Canada Thistle (PDF) – OSU Extension Bulletin EC1590
- Musk thistle identification and control – King County Noxious Weed information
- Musk Thistle – WA State Noxious Weed Control Board information
- Musk Thistle (PDF) – Lincoln County Noxious Weed Fact Sheet
- Control Options for Canada Thistle and Bull Thirstle (PDF) – Whatcom County Noxious Weed Fact Sheet
- Bull Thistle (PDF) – Whatcom County Noxious Weed Fact Sheet
- Bull thistle identification and control – King County Noxious Weed information
- Invasive Weeds in Forestland: Bull Thistle (PDF) – OSU Extension Bulletin EC1588
- Canada Thistle (PDF) – Whatcom County Noxious Weed Fact Sheet
- Canada thistle identification and control – King County Noxious Weed information
- Invasive Weeds in Forestland: Canada Thistle (PDF) – OSU Extension Bulletin EC1590
- Musk thistle identification and control – King County Noxious Weed information
- Musk Thistle – WA State Noxious Weed Control Board information
- Musk Thistle (PDF) – Lincoln County Noxious Weed Fact Sheet
- Control Options for Canada Thistle and Bull Thirstle (PDF) – Whatcom County Noxious Weed Fact Sheet
Yellow archangel (Lamiastrum galeobdolon)
- Yellow Archangel (PDF) – Whatcom County Noxious Weed Fact Sheet
- Yellow archangel identification and control – King County Noxious Weed information
- Yellow Archangel – WA State Noxious Weed Control Board information
- Yellow Archangel (PDF) – Whatcom County Noxious Weed Fact Sheet
- Yellow archangel identification and control – King County Noxious Weed information
- Yellow Archangel – WA State Noxious Weed Control Board information
Yellow toadflax (Linaria vulgaris)
- Yellow toadflax (PDF) – Whatcom County Noxious Weed Fact Sheet
- Yellow toadflax identification and control – King County Noxious Weed information
- Yellow toadflax – WA State Noxious Weed Control Board information
- Yellow toadflax (PDF) – Whatcom County Noxious Weed Fact Sheet
- Yellow toadflax identification and control – King County Noxious Weed information
- Yellow toadflax – WA State Noxious Weed Control Board information
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