Houndstongue

Cynoglossum officinale

Boraginaceae (Borage family)

Class B-Designate Noxious Weed

Control Required

Houndstongue, a member of the borage family, is a Class B-Designate Noxious Weed. It likely arrived from Europe as a contaminant of cereal seed. It is a biennial (two year life cycle) with a thick woody taproot. Houndstongue leaves are hairy and rough, feeling and appearing like a dog's tongue.

Houndstongue tolerates shade and grows well in wet areas. In its first year of growth, houndstongue produces a large leafy rosette. The second year it produces flowering stalks and fruit. Flowers are reddish purple and become seed nutlets, which are covered in tiny, Velcro-like barbs that stick easily to fur and clothing. This is the primary way houndstongue spreads.

Houndstongue is a strong competitor of desirable forage and commonly invades pastures, roadsides and disturbed areas. It is a toxic plant with the potential to poison domestic animals and wildlife.