Wavy-Leaved Thistle, Tracy's thistle
Cirsium undulatum
Family: Asteraceae or Compositae
What it is like
Cirsium undulatum is a PERENNIAL growing to 0.6 m (2ft). The species is hermaphrodite (has both male and female organs) and is pollinated by Bees, flies, Lepidoptera (Moths & Butterflies), beetles. The plant is self-fertile. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It cannot grow in the shade. It prefers dry or moist soil.
Height (m): 0.6
Where it is found
Dry open soils. Prairies, pastures and roadsides in Texas.
Western N. America - British Columbia to Texas.
Conservation Status: This taxon has not yet been assessed.
Countries/locations it is found in
Native to much of central and western North America from British Columbia east to Manitoba and south as far as the State of Durango in Mexico. It has also been found outside of its native range as an introduced species.
How it is used
Food
Rating: 3
Root - raw or cooked. One of the more palatable thistles, it is used as a vegetable or can be added to soups and stews. It can be dried and stored for winter use. The root is likely to be rich in inulin, a starch that cannot be digested by humans. This starch thus passes straight through the digestive system and, in some people, ferments to produce flatulence. Stems - peeled and eaten raw or cooked. One of the more palatable thistles.
Oil: Oil
Root: includes bulbs, corms, tubers, rhizomes etc.
Stem: this often intergrades into leaves.
Medicine
Rating: 1
A decoction of the root has been used in the treatment of gonorrhoea. A cold infusion of the root has been used as a wash for eye diseases.
Ophthalmic: Treats eye complaints.
VD: Used in the treatment of venereal disease
Other
Rating: 2
The seed of all species of thistles yields a good oil by expression. No details of potential yields etc are given.
Oil: Vegetable oils have many uses, as lubricants, lighting, soap and paint making, waterproofing etc. This does not include the edible oils unless they are also mentioned as having other uses.
How it is grown
We have very little information on this species and do not know if it will be hardy in Britain, though judging by its native range it should succeed outdoors in many parts of this country. The following notes are based on the general needs of the genus. An easily grown plant, succeeding in any ordinary garden soil in a sunny position.
Propagating it: Seed - sow early spring or autumn in situ. Germination usually takes place within 2 - 8 weeks at 20°c.
Best place to grow: Cultivated Beds;
Habit: Perennial
Hardiness: 0-0
Growth:
Soil: Light (sandy), medium, heavy (clay)
Shade: No shade
Moisture: Dry, moist
Things to keep in mind
This plant can be weedy or invasive. It is a weed in California and Northwestern Mexico. Know as a Noxious Weed in: Arkansas, California and Iowa, USA
Its other names
Local names
Gray thistle, Wavyleaf thistle, Wavy-Leaved Thistle, Tracy's thistle