MAILING ADDRESS: 1120 SW 5th Ave, Room 1000, Portland, OR 97204
Blessed milk thistle presents something of a dilemma. On the one hand, it is grown for the herbal supplement market; on the other hand, it has escaped cultivation and is over-running parts of Australia and California. For the time being, milk thistle is uncommon in northwest Oregon. Still, it’s been sighted in several locations out of cultivation along the Columbia Slough and on Sauvie Island, and is relatively more common in Clark County, Washington. Blessed milk thistle is a Required Eradication species in Portland.