|
Department of Natural Resources
Illinois
Exotic Species:
cut-leaved teasel Dipsacus laciniatus
Cut-leaved
teasel is native to Europe. It was introduced to North America possibly
as early as the 1700's. Cut-leaved teasel may have been introduced with
other teasel species or accidentally with other plant material from Europe.
Cut-leaved
teasel grows as a basal rosette for at least one year then sends up a
flowering stalk and dies after flowering. During the rosette stage leaves
are oval to oblong and may be quite "hairy." Cut-leaved teasel
blooms from July through September. Flowering plants have large, oblong,
opposite, sessile leaves that form cups (the cups may hold water) and
are prickly. Stems also are prickly. Teasel's unique flower head makes
the plant easy to identify when it is blooming. Flowers are small and
packed into dense oval-shaped heads. The heads are located at the tip
of the flower stems. Cut-leaved teasel usually has white flowers. Flowering
stems may reach six to seven feet in height. A single teasel plant can
produce more than 2,000 seeds. Teasel grows in open sunny habitats, ranging
from wet to dry conditions. Cut-leaved teasel sometimes occurs in high
quality prairies, savannas, seeps and sedge meadows, though roadsides,
dumps and heavily disturbed areas are the most common habitats of teasel.
Teasel has
spread rapidly in the last 20 to 30 years. This rapid range expansion
probably was aided by construction of the interstate highway system. Teasel
has colonized many areas along interstates. The use of teasel in flower
arrangements has aided its dispersal, too. Teasel occurs widely in northern
and central Illinois. Teasel is an aggressive exotic species that has
the capacity to take over prairies and savannas if it is allowed to become
established.
Exotic
Species Photo Gallery | Exotic
Species Intro Page | Wild
About Animals | Wild
About Plants
|