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 management practices
Pacific Northwest Handbooks: Weed Management 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

Our most problematic forest weeds

General resources and manuals

State and County noxious weed agencies

Aquatic weed general resources

Notes:

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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 Management 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

Aquatic weed general resources

Water Weeds: Guide to Aquatic Weeds in King County – King County Noxious Weed Program
Aquatic Weed Identification 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

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

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

Gorse (Ulex europaeus)

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 – Washington 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

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

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

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

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

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

Oxeye daisy (Linaria vulgaris)

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

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

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

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

Sulfur cinquefoil (Potentilla recta)

Sulfur cinquefoil (PDF) – Whatcom County Noxious Weed Fact Sheet
Sulfur cinquefoil identification and control – King County Noxious Weed information

Tansy ragwort (Jacobaea vulgaris)

Management of 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 Thistle (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 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

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