Cirsium arvense (Linnaeus) Scopoli
The words or terms in red
(actually dark orange) in the text are defined in a
Cirsium arvense is a persistent
perennial that grows vigorously,
forming dense colonies and spreading by roots growing horizontally
that give rise to aerial shoots. Plants generally grow one to four feet tall,
but on occasion may grow more than six feet tall and branch freely. Stems are
smooth, mostly without spiny wings, green and
glabrous. Flower heads are numerous, small,
and almost spineless. Flowers are purplish lavender or, less commonly, white.
Cirsium arvense is native
to southeastern Europe and the eastern
Mediterranean area. It has spread to most temperate parts of the world and is
considered an important weed in thirty-seven countries. It is particularly
troublesome in cooler areas of North America, extending from coast to coast in
both Canada and the United States. It was introduced into North America in the
seventeenth century by French settlers as a contaminant in crop seed.
It occurs in nearly every upland herbaceous community within its range,
and is a particular threat in grassland communities and
Numerous variants of Cirsium arvense have been named based upon such
features as pubescence,
extent of leaf division, and spininess. Although extreme
variants can be strikingly different, they are connected by such a web of
intermediates that there seems to be little value in according any of them
formal taxonomic recognition.
Cirsium arvense belongs to the
family. It has a
chromosome number (n2) of 34.
In Greek κιρσιον
(kirsion) is the name of a Thistle that was used to heal varicose
veins, and κιρσοσ
(kirsos) means varicose vein, kirsion being then the
(bygone) remedy of kirsos. As for Thistle it is the common
vernacular of most
Cirsium species (and of some
Carduus species too).
In Latin arvum means land that can be ploughed, field
and arvus means that can be ploughed;
the derived arvense epithet applies
quite well to the species that is found in fields and crop land.
Some of the vernacular names of
Cirsium arvense are: Canada Thistle, California Thistle,
Creeping Thistle, Corn Thistle, Cursed Thistle, Green Thistle, Hard Thistle,
Small-flowered Thistle, Way Thistle, Perennial Thistle and
Cirsium arvense has also been known as:
- Carduus arvensis (L.) Robson
- Cirsium arvense (L.) Scop. var. argenteum (Vest) Fiori
- Cirsium arvense (L.) Scop. var. horridum Wimmer & Grab.
- Cirsium arvense (L.) Scop. var. integrifolium
Wimmer & Grab.
- Cirsium arvense (L.) Scop. var. mite Wimmer & Grab.
- Cirsium arvense (L.) Scop. var. vestitum Wimmer & Grab.
- Cirsium incanum (Gmel.) Fisch.
- Cirsium setosum (Willd.) Bess. ex Bieb.
- Serratula arvensis L.
Cirsium arvense could be confused with various
Carduus species, and with Cirsium vulgare,
but Cirsium arvense is the only Cirsium and the only
with male (only with stamens)
with female (only with anthers)
flowers on separate plants, male and female flowers that can be readily
distinguished, the later by the absence of
Furthermore, the stems of Cirsium arvense
are spineless unlike Cirsium vulgare and Carduus nutans.
Cirsium arvense is a 1 to 4 ft (30 to 120 cm) tall plant with green
foliage. It forms an extensive underground root system that sends up numerous
erect stems each spring.
- Smooth, mostly without spiny wings.
- Green and glabrous.
- Branching near the apex, hollow.
- With variable margins,
from entire to deeply
- Measuring from 2 to 8 inches in length.
- Sessile, slightly clasping or
- With spines along the margins,
1/8 to 2/8 inch (3 to 5 mm) long.
- The upper surface of mature leaves dark green, the lower surface
- Single and terminal, in loose
- From 0.4 to 1 inch (1 to 2.5 cm) in diameter and about 1 inch tall.
- Rounded or flat-topped.
- With an hemispheric to ovoid
- The outer phyllaries ovate,
tipped with stout spines 1 mm long,
the inner phyllaries progressively longer with tips flattened.
- Without ray florets.
- With tubular disk florets,
either all pistillate or
staminate since the plant are
- With the corolla of the staminate
florets somewhat smaller (1/2) than those of the pistillate florets.
- Florets generally purplish lavender to, less commonly, white.
- Pollination is almost exclusively by
- Male and female plants growing in close proximity resulting
in high rates of seed production, with some plants producing over 5,000
- Blooming from July to September in my area, 25 km North of Montréal.
- Light brown achenes about 3 mm long.
- Slightly grooved along long axis, flattened.
- With an abundant white and feathery, fragile
easily separated from the seed, and about 3/4 inch long.
Cirsium arvense grows on a variety of soil types. It grows on all but
waterlogged, poorly aerated soils, including clay, clay
silt loam, sandy loam, sandy clay,
sand dunes, gravel, limestone, and chalk, but not peat. It does well on deep,
well aerated, moist loam soils, but is known
to grow in dry habitats and on sandy soils. It may also grow on stream banks,
in meadows, and even in wet ditches, but it will not survive in saturated soil.
It is intolerant of shade, requiring good light conditions for aggressive
Native to southeastern Europe, the eastern Mediterranean, and possibly northern
Europe, western Asia, and northern Africa, Cirsium arvense has now a
near global distribution between 37 and 58 to 59 degrees North in the northern
hemisphere, and at latitudes greater than 37 degrees South in the southern
hemisphere, exclusive of Antarctica. It occurs throughout Europe, northern
Africa, western and central Asia, northern India, Japan, China, northern North
America, South Africa, New Zealand, Tasmania, and southeastern Australia.
The map show the USA States and Canadian provinces and territories provinces
where the plant can be found.
Cirsium arvense infests many habitats such as cultivated fields,
roadsides, pastures and rangeland, railway embankments, and lawns. In the US,
it is a major pest in streamside grasslands from the Pacific Northwest eastward
to the plains. It also invades moist prairies.
Once established, it spreads rapidly by horizontal roots, up to several meters
per year. The extensive horizontal root system assures long-term persistence
and spread by vegetative means. A segment of root as small as 1/8 to 3/8 inch
(3 to 6 mm) in length and 1/16 inch (1 mm) in diameter is able to propagate a
new plant and is easily spread with plant material or by equipment.
Sheep and cattle graze on Cirsium arvense when the plants are young and
tender, helping to deplete the root reserves.
American Indians purportedly used an infusion of Cirsium arvense
roots for mouth diseases. The Chippewa considered it to be a tonic,
Young shoots and roots, used in the same ways as asparagus, and were eaten in
Russia and by Native Americans.
The nectar of the flowers is also said to make good honey.
The plant has been used by native people in the northeastern United States in
remedies for worms and poison-ivy (Toxicodendron radicans) and was used
to make a mouthwash for children, a treatment for tuberculosis,
and a tonic for gastrointestinal ailments.
The photos of the gallery were taken either with one of the following:
The title in the window shows the date when the picture was taken,
i.e. jan_30_06... would mean that the photo was taken on the 30th of
January, the 06 is for the 6th picture taken that day.
- Minolta DiMAGE 7.
- Canon PowerShot A530
- Canon Xt Rebel, usually with the EF-S60mm f/2.8 Macro USM objective.
- EPSON Perfection 1650 (scanner).
The month, day and picture number might be followed by a letter:
- c for the Canon Xt Rebel.
- a for the Canon A530.
- m for the Minolta DiMAGE 7.
- s for the EPSON scanner.
Click on the thumbnails to get larger view.
The original photos are usually in TIFF format,
the photos shown are generally in JPEG format,
usually of dimensions one half (surface one quarter)
for loading time reduction.
The leaves were scanned at 300 dpi,
this allows to measure the dimensions of the leaves.