teasel (Dipsacus fullonum)
Dipsacus fullonum L. ssp. fullonum
Dipsacus fullonum L. ssp. sylvestris (Huds.) Clapham
Dipsacus sylvestris Huds.
CONFIRMATION STATUS: Pending confirmation.
TAXONOMY: The currently accepted scientific name of teasel is
Dipsacus fullonum L.
NATIVE STATUS: Introduced, United States and Canada.
GENERAL BOTANICAL CHARACTERISTICS:
Habit: This introduced biennial plant consists of a low rosette of basal
leaves during the first year. These basal leaves are up to 12" long and 3"
across, oblanceolate, and crenate. During the second year, teasel develops
stems with opposite leaves, becoming 2½-6' tall; it branches occasionally
and is rather lanky. The hairless stems are pale green to reddish green;
they have scattered white prickles and flat longitudinal ridges.
Leaves: The opposite leaves are up to 12" long and 3" across; they are
green, yellowish green, or reddish green, lanceolate to linear-lanceolate, ascending to spreading, and rather stiff in texture. Their margins are
smooth, slightly prickly, or irregularly toothed. On the upper surface of
each leaf, there is a white central vein, while on the lower surface this
vein has stout prickles. The lower opposite leaves are sessile, while the
upper opposite leaves are perfoliate or clasping. All leaves are hairless.
Flowers: Each upper stem terminates in a stout spike of flowers up to 4"
long and 1½" across; the long flowering stalk is naked and prickly. Initial-
ly, each floral spike is ovoid in shape, but it later elongates and becomes
oblongoid. At the base of each floral spike, there are several linear bracts
up to 6" long that curve upward, surrounding the spike. These bracts have
scattered prickles on their sides and undersides. Narrow tubular flowers
and their buds are densely crowded together all around the spike. These
flowers begin to bloom in the middle of the spike, but later they bloom in
separate rings toward the top and bottom of the spike. The corolla of each
flower is narrowly tubular and about ½" long; it has 4 outer lobes that are
small and rounded. The corolla is usually pale purple or lavender toward
the outer lobes, but it is white toward the base. Each flower has 4 exerted
stamens with white filaments and pale purple or lavender anthers. The
calyx is tiny and insignificant. At the base of each flower, there is a bract
originating from the receptacle that is straight and about the same length
as the flower. This bract is usually pale green, stiff, and linear in shape.
However, the bracts of the receptacle toward the apex of the floral spike
are significantly longer than the flowers. Like the flowers, these bracts are
densely crowded all around the floral spike, providing it with a pincushion-
like appearance after the flowers have withered away. After the blooming
period, the entire plant gradually turns brown; the stalks and floral spikes
persist through the winter.
Fruit/Seeds: Each flower is replaced by a ridged 4-angled achene that is irregularly bullet-shaped and up to ¼" long.
Roots: The root system consists of a stout taproot.
REGENERATION PROCESS: Teasel propogates itself by reseeding.
HABITAT TYPES: It was introduced from Eurasia. Habitats include
mesic prairies (especially cemetery prairies), degraded grassy meadows,
savannas, woodland borders, pastures and abandoned fields, rough grass-
lands, hedgerows, thickets, landfills, roadsides including road verges, and
waste areas. Teasel is an introduced species that can invade high quality
prairies and savannas. It is difficult to eliminate from such habitats. Teasel
also adapts readily to disturbed habitats. It thrives in areas where heavy
soils have been disturbed.
SITE CHARACTERISTICS: Teasel prefers full or partial sun, mesic
conditions, and mildly acid to alkaline soil containing loam or clay-loam.
The leaves are occasionally bothered by powdery mildew.
SEASONAL DEVELOPMENT: The blooming period occurs from mid-
summer into fall and typically lasts about 2 months for a colony of plants.
GENERAL DISTRIBUTION: Teasel is found throughout much of the
United States. It has not been recorded in the extreme southeastern portion (Florida, Georgia, and South Carolina) nor in Maine or the Canadian mari-
time provinces. The only other states not reporting Dipsacus fullonum are Louisiana, Minnesota, and North Dakota. Also, the three prairie provinces
of Manitoba, Saskatchewan, and Alberta have not reported its occurrance, although British Columbia has. It does not occur in the northern territories.
SKY MEADOWS DISTRIBUTION: To be determined.
IMPORTANCE AND USES: The nectar of the flowers attracts bumble
bees and other long-tongued bees, green metallic bees (Agapostemon spp.),
bee flies, butterflies, and skippers. Green metallic Bees also collect pollen.
The caterpillars of the Papaipema arctivorens (northern burdock borer
moth) bore through the stems of Dipsacus spp. (Teasels). Mammalian herb-
ivores shun the tough prickly foliage of teasel; even in overgrazed pastures,
cattle nibble on the outer tips of the leaves and little else. Except for flower-visiting insects, the ecological value of this introduced species to wildlife is
Teasels earn their name as the spiky flower heads were used to comb wool-
len cloth, to 'tease' out the fibres prior to spinning (from the Old English
teasan, meaning to tease). The heads of fuller's teasel (Dipsacus sativus)
have curved spines; they were also used to raise the pile, or 'nap' of cloth.
In horticulture, the dried floral spikes and their stalks are used in dried
flower arrangements. In the past, the floral spikes and stalks were used as material in funereal wreaths, which were placed alongside the gravestones
of the deceased. This is one of the reasons why teasel occurs in cemetery
During the eighteenth century, the water collected by the leaves of teasels
was thought to remove freckles. It has also been used to soothe sore eyes.
The roots have been used to treat warts, sores, and other skin problems.
Crooked Run Valley