- Dipsacus fullonum
Teasel (Dipsacus fullonum) is a biennial or sometimes a perennial weed that prefers open, sunny areas, and will tolerate a range of wet to dry conditions. It is found in pastures, meadows, disturbed areas and along roadsides. Teasel is too prickly and bitter to be eaten by wildlife or livestock, reducing available forage and out-competing native vegetation.
Teasel has prickly, highly branched stems that support bristly, egg-shaped purple to white flowers. Flowers bloom in rows starting from the middle of the flower head. It has a strong taproot, and grows up to 7 feet tall. Though plants typically die after flowering the first time, it spreads successfully by seed. A single plant can produce more than 2,000 seeds, with 30-80 per cent germination success the following spring. Seeds can remain viable for at least two years.
Teasel was used in wool "fleecing" (raising the nap on woolen cloth), making it a valued horticulture plant that led to its introduction in North American as early as the 1700s. It escaped cultivation and is spreading rapidly throughout the U.S. except in the northern Great Plains.