Backyard Gardening

By Kathryn Dorman

I’ll admit it, I am a Clint Eastwood fan.  I really enjoy Clint’s later films, such as “Space Cowboys,” and “Gran Torino.”  I can even appreciate his detective movies, with iconic one-liners like “Go ahead, make my day.”  I’m not as enthusiastic about Eastwood’s westerns, although I do recognize the theme song from “The Good, the Bad, and the Ugly.”  When I hear it, I get nostalgic for the days when I could move with the flexibility of youth…  But let me get to the subject of this article:  teasel.  Teasel was considered to be good, until it was bad.  Since teasel’s leaves are somewhat warty, and its stems and flowers are prickly, a field of teasel can look and feel ugly.  

Teasel is mostly considered to be a biennial plant, although sometimes it lives for more than two years.  In the first year or so after seed germination, teasel forms a deep taproot (which can be up to two feet long), and a rounded grouping of puckered leaves with scalloped edges.  This is called a basal rosette, which grows at ground level, and can survive through winter.  Once the rosette has grown large enough, typically in the second year, long stems will shoot up, which can be up to eight feet in height.  Stem leaves look similar to rosette leaves, but are smaller and more narrow.  Their bases fuse to form a cup around the stem that can hold water.  These little pools may prevent aphids and other sap-sucking insects from climbing the stems.  The stems will often have two or more branches, with cone-shaped flower heads developing at the top of each branch.  The flowers are small, and only last for a day.  Once it flowers, the plant dies, but the flower heads often stay in place throughout the winter.

Many reputable resources place the teasel species (genus Dipsacus) into the honeysuckle, or Caprifoliaceae, family.  Other sources classify teasel in a family all by itself, Dipsacaceae.  According to the National Park Service, “dipsacus comes from the Greek word dipsa, which means ‘thirst.’  It refers to teasel’s fused leaf bases that collect rainwater (https://www.nps.gov/articles/common-teasel.htm).”

The two main species of teasel currently growing in the United States are common teasel (D. fullonum) and cutleaf teasel (D. laciniatus).  Both species are native to Europe and temperate Asia.  Common teasel is also native to northern Africa.  It is also known as fuller’s teasel, barber’s brush, brushes and combs, and card teasel.  Fullonum is a reference to the process of ‘fulling’ wool, in which the cloth is thickened by moistening, heating, and pressing.

According to Corey Gucker, of the United States Department of Agriculture, the leaves of D. fullonum are oval, with toothed or wavy margins.  D. laciniatus has deeply lobed leaves, with spines on the margins.  Fuller’s teasel typically produces lavender flowers.  Cutleaf teasel flowers are generally white (https://www.fs.fed.us/database/feis/plants/forb/dipspp/all.html).  I found two different kinds of teasel plants growing in disturbed areas near local stores.  One had white flowers, the other had lavender flowers.  I did NOT see any lobed leaves to indicate cutleaf teasel (See Photos One and Two).

Author Jacqueline Stuhmiller writes about Skaneateles, in the Finger Lakes region of upstate New York.  During the 1800’s and early 1900’s, this town was the center of the agricultural teasel industry.  Teasel was cultivated in Skaneateles for domestic use within the U.S., and was even exported to Europe.  The bristly seed head of the teasel flower was used to card wool.  This process separated and aligned short wool fibers in preparation for spinning them into threads, which could then be woven into fabric (https://www.gofingerlakes.org/teasel-our-prickly-relationship/).

The word teasel, derived from the Old English taesan, literally means ‘to tease or pull apart.’  During the 1800’s, teasel heads were used in woolen mills to raise the nap on woven fabric, creating a soft, almost furry texture.  The covering on a pool table, called baize, is made of teased wool.  Teasing wool produces the soft feel and drape of cashmere.  Teasel heads were very good for this purpose, but wore out quickly, and had to be constantly replaced.  Consider that Clinton County’s very own Woolrich Woolen Mill was established in 1830 (https://www.woolrich.com/us/en/woolrich-history/brand-history.html).  Before fine wire brushes were invented, they must have used teasel in a very labor-intensive process.  The use of teasel in woolen mills was eventually phased out in the mid-1900’s, when foreign competition forced the U.S. woolen industry to adopt cheaper, more efficient manufacturing processes using increased automation.

Teasel has also been used in dried floral arrangements.  Teasel flowers left at gravesites eventually dropped their seeds to the ground.  This could explain why common teasel is often found in and around cemeteries.  Today, teasel grows almost everywhere in North America, except central Canada, the northern Great Plains, and several southeastern states.  Please note that teasel can contribute to a balanced ecosystem.  Many butterflies, moths, and bees often visit teasel flowers for nectar.  Small mammals, such as mice, and many bird species will eat teasel seeds, including bobwhites, quail, ring-necked pheasants, and goldfinches.

On the other hand, the National Park Service says that “common teasel tends to infest areas along roadways and waterways, in meadows, grasslands, forest openings, and disturbed sites.”  According to Wendy Ferguson, of the University of Illinois Extension, there are at least three ways in which teasel has the potential to become invasive: (1) Teasel can produce thousands of seeds from a single plant.  (2) Teasel can crowd out other plants.  This can lead to a loss of biodiversity, possibly upsetting the local ecosystem’s balance.  (3) Teasel plants can quickly produce flowers on very short stalks even after the original, longer stalks have been cut down (https://extension.illinois.edu/blogs/flowers-fruits-and-frass/2021-05-29-how-non-native-teasel-went-good-absolutely-bad).  Some states have already declared teasel to be noxious, including Colorado, Iowa, New Mexico, Minnesota, Missouri, and Washington.  A noxious weed is considered to be so invasive that it is illegal to grow, sell, or transport seeds, live plants, or plant parts across state lines.

How can teasel be controlled?  Smaller basal rosettes can be dug out of the ground.  Larger rosettes can be difficult to dig out, due to their deep, thick taproot.  Remove as much of the taproot as possible, going down at least one to two inches below the soil surface.  Once flowering has begun, the flower heads can be cut off and removed.  Please dispose of them properly, by burning or placing in the trash.  Do NOT compost!  Replace the teasel plants with a variety of (preferably native) more desirable plants.  I don’t like to use herbicide.  If you think it is needed, please refer to the PNW Weed Management Handbook (https://pnwhandbooks.org/weed/control-problem-weeds).

Sometime in the early years of our marriage, my husband’s grandmother gave me a really cute Christmas ornament, made out of a dried teasel flower.  It was a mouse, dressed up as Mrs. Claus, complete with gold-rimmed glasses.  I would like to make more craft items out of teasel.  So far, I have only made a mental note where teasel can be found growing along the roadsides.  I have seen pine cones made into wreaths or owls.  Similar items could be made with dried teasel flowers.  If you decide to do something crafty with teasel, please first shake out and properly dispose of the seeds.  This will prevent the spread of even more teasel plants.

Kathryn Dorman has been a Penn State Extension certified Master Gardener since 2017.  She can be reached at clintonmg@psu.edu or through the Clinton County Master Gardener Hotline at (570) 858-0198.