Bull Thistle

Common Name: Bull Thistle.

Scientific Name: Cirsium Vulgare.

What to look for?  Weedy-looking plant with lovely purplish-pink tubular flowers atop a spikey globe. The Bull Thistle has moderate height with occasional lateral branches from its main stem that remain erect. The angular stems are light green with noticeable white hairs. The leaves are long and quite spiny. They are dark green on the upper surface and light green on the lower surface. Flowerheads are a purplish pink and consist of numerous long, tubular disk florets. After the bloom period ends, the florets wither away. They are replaced by long, slender achenes or seeds with large tufts of white hair. These seeds are dispersed by the wind, which is the primary means for the plant to spread. The root system consists of a stout taproot that runs deep into the ground.

Where can they be found at Carillon Stonegate Pond? Bull Thistle pop up in the meadow areas around Carillon Stonegate Pond and around the fields near Arlene Shoemaker forest preserve.

How big are they? Bull Thistle grows from three (3) feet up to six (6) feet tall. The narrow and oval leaves are approximately seven (7) inches long and two (2) inches across. Each flower head is approximately one (1) to two (2) inches across.

Where do they grow and thrive? The non-native Bull Thistle occurs across most areas of Illinois. Across the U.S., this plant is found in most states with greater concentration in the western and northern states. Habitats include pastures, abandoned fields, fence rows, areas along roadsides and railroads, and cut-over woods. This Bull Thistle prefers disturbed areas and is not common in high quality natural areas.

When do they bloom? The blooming period of the Bull Thistle occurs from mid- to late summer and lasts about one (1) month.

Do birds, insects or other wildlife associate with this plant? The nectar and pollen of the Bull Thistle’s flowers attract many kinds of long-tongued bees, including bumblebees. The flower nectar also attracts butterflies - especially swallowtails and skippers. The Painted Lady caterpillars feed on the foliage. The seeds are eaten by the American Goldfinch and several other birds. Other animals avoid this plant because of the spines.

Interesting Facts About the Bull Thistle:

  • Bull Thistle flowers bloom two to three weeks after other thistles.

  • Bull Thistle is a biennial plant that only forms a wide rosette in its first year, before it blooms in its second year.

  • In nine states, but not Illinois, it is classified as a noxious weed.

  • The Bull Thistle also has spines on its stems, while the stems of native thistles are spineless.

For more information on the Bull Thistle and sources of information used in this blog (these are several of the sources that I am using to learn as I blog), please visit Illinois Wildflowers, Minnesota Wildflowers, Friends of the Wildflower Garden, and the U.S. Forest Service.

The Carillon at Stonegate community is very fortunate to have a variety of wetland, forest and prairie environments conducive to a variety of birds and other wildlife, insects and plants. Our community and the Kane County Forest Preserve do an exceptional job in maintaining this natural environment – both for the benefit of the birds and wildlife and for our residents to enjoy.

 

Take a hike and see what you can find – and identify!