(360) 740-1215 Address

Weed Control Pages

  • Meadow knapweed

    Meadow knapweed – Upright stems, 20 – 40 inches tall, leaves up to 6 inches long and 1 ¼ inch wide, rose-purple flowers the size of a nickel appear in July/August. Invades moist sites including pastures, meadows, and roadsides. Found in Winlock, Vader and the Packwood area. Weed Classification: B

  • Purple Loosestrife

    Purple loosestrife – Erect squarish stems, up to 9 feet tall, leaves 1 ½ to 4 inches long, spikes of magenta flowers 4 – 16 inches long, flowers from July to October. Invades fresh water, wetland areas. Found in wetlands and streams in the Centralia/Chehalis area as well as Stearns Creek and Mineral Lake in Lewis County. Weed Classification: B

  • Brazilian Elodea

    Brazilian elodea – Erect stems with leaves that are 1 – 3 cm long and 5 mm broad, 18 –25 mm white flowers with three petals. Grows submersed in fresh water such as ponds, lakes and quiet streams. Found in Plummer Lake and the Chehalis River in Lewis County. Weed classification: B

  • Eurasian Watermilfoil

    Eurasian Watermilfoil – Feathery underwater foliage, 12 or more pairs of leaflets on each leaf, leaves in whorls of 4 around the stem. Grows in still to flowing waters under many different environmental conditions. Found in Lake Scanewa, Swofford Pond, Mayfield Lake and South County Park in Lewis County. Weed classification: B

  • Tansy Ragwort

    Tansy Ragwort – Upright stems, 1 – 4 feet high, leaves alternate, clusters of yellow daisy like flowers, poisonous to livestock. Grows in disturbed sites, including pastures and roadsides. Primarily found in central and western Lewis County. Weed classification: B Select

  • Invasive knotweeds

    Invasive knotweeds – Bamboo like stems that grow 4 – 8 feet tall, heart shaped leaves 4 – 6 inches long, white flowers appearing in August – September. Escaped ornamental invades riparian areas and roadsides. Found along many creeks and rivers in Lewis County, including the Cowlitz River, Tilton River and Chehalis River. Weed classification: B Select

  • Scotch Broom

    Scotch broom – Shrub, 1 – 2 meters high, leaves 6 – 12 mm long, yellow flowers bloom between April and June. Grows in pastures, roadsides, riverbeds and other disturbed areas. Is present in all areas of Lewis County. Weed classification: B Select

  • Butterfly Bush

    Butterfly bush – Shrub, Grows up to 15 feet tall, leaves 4 – 10 inches long and 1 – 3 inches wide, 4 – 10 inch long flowers spikes usually purple in color, blooms in mid-summer. Common in landscapes, concern is escape to riparian areas and along roadways. Weed classification: C Select

  • Poison Hemlock

    Poison hemlock – Erect Stem, 4 – 8 feet tall with mottled purple spots, finely divided leaves, lacey white flowers in late May to August, poisonous to humans. Primarily found in urban areas, alleys, vacant lots and along rail lines in Lewis County. Weed classification: C Select


The County Weed Board works to develop programs that reflect local priorities, meets the needs of county landowners and carries out the mandate of the Washington State noxious weed law. The Weed Program provides weed prevention strategies, education programs, technical assistance and compliance actions to control or eradicate noxious weeds.

Contact Weed Control

Weed Control
351 NW North Street
Historic Courthouse, Ground Floor #008
Chehalis WA 98532
(360) 740-1215