Hoary alyssum

Berteroa incana

Hoary Alyssum1
Hoary Alyssum2
Hoary Alyssum3
Hoary Alyssum4

Hoary Alyssum - Plant is usually silvery-gray in appearance due to stellate hairs. 1-3.5 feet tall and functions as an upright annual, biennial, or short-lived perennial.

Leaves: Plant has basal leaves that are larger and oblanceolate. Leaves gradually reduce in size moving up the stem with alternate leaf arrangement.

Flowers: Blooming from May-August. Flowers bloom from the bottom up in simple or branches clusters. Petals are white and are two times longer than sepals and are deeply cleft. 6 stamens per flower.

Habitat: Plant is adapted to dry conditions. Usually is found in overgrazed pastures, stressed meadows, roadsides, and waste areas. Prefers sandy and gravelly soils.

Weed Classification: B Designate

Why is it a Noxious Weed?

Invades pastures and generally out-competes beneficial plants by spreading quickly. Livestock are known to become affected after eating green or dried plants. Has been noted for animal poisoning and potential death.

No known infestations currently in Lewis County. Hay has been purchased and imported into the county that contained Hoary Alyssum, which could potentially cause the plant to spread through seeds. Please inform us of any suspected infestations of Hoary alyssum becoming established!

Control Recommendations:

WA State Noxious Weed Board

PNW Pest Management Handbook

UC Davis Weed Report