Cutleaf teasel
(Dipsacus laciniatus)
A biennial, sometimes perennial, plant native to Europe, cutleaf teasel reproduces from seed and has recognizable whitish egg-shaped flowers at the top of each stem. These flowers have floral bracts at the base of the head that are longer and wider than those of the Common teasel. The oppositely arranged leaves are large, oblong, and prickly, and are conspicuously veined in the rosette stage.
The plant can grow to over ten feet in height and can produce up to 2,000 seeds that will remain viable for 2 years. There have been no reported sightings in Garfield County at this time.