Invasive Forest Weeds Resources

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General noxious weed resources

State and county noxious weed agencies

Aquatic weed general resources

The worst forest offenders: A selection of resources

Absinth wormwood (Artemisia absinthium)

Butterfly bush (Buddleja davidii)

Common St. Johnswort (Hypericum perforatum)

Common tansy (Tanacetum vulgare)

English hawthorn (Crataegus monogyna)

English holly (Ilex aquifolium)

English ivy (Hedera helix)

European mountain-ash (Sorbus aucuparia)

Garlic mustard (Alliaria petiolata)

Giant hogweed (Heracleum mantegazzianum)…Dangerous!

Gorse (Ulex europaeus)

Hawkweeds, orange and yellow (Hieracium aurantiacum and Hieracium caespitosum)

Herb-Robert (Geranium robertianum)

Himalayan and evergreen (cut-leaf) blackberry (Rubus armeniacus and Rubus laciniatus)

Houndstongue (Cynoglossum officinale)

Knapweeds, spotted, diffuse, and meadow (Centaurea stoebe, Centaurea diffusa, and Centaurea jacea x nigra)

Knotweeds (Polygonum sachalinense, P. cuspidatum, and P. x bohemicum)

Old man’s beard (Clematis vitalba)

Oxeye daisy (Linaria vulgaris)

Poison-hemlock (Conium maculatum)

Reed canarygrass (Phalaris arundinacea)

Scotch, French, Spanish, and Portuguese brooms (Cytisus scoparius, Genista monspessulana, Spartium junceum, and Cytisus striatus)

Spurge laurel (Daphne laureola)

Sulfur cinquefoil (Potentilla recta)

Tansy ragwort (Jacobaea vulgaris)

Thistles, Canada, bull, and musk (Cirsium arvense, Cirsium vulgare, and Carduus nutans)

Yellow archangel (Lamiastrum galeobdolon)

Yellow toadflax (Linaria vulgaris)

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