Agronomy 517

Spring Semester 2000

4.14.00

References: Literature Cited

Outline for Cirsium arvense(L.)Scop.

Prepared by Brad Atchison

I. scientific name Cirsium arvense (L.)Scop.

2. California Thistle

3. Field Thistle

4. Creeping Thistle

1.Cirsium arvense (L.) Scop. var. argenteum(Vest)Fiori.

2.Cirsium arvense (L.)Scop. var. horridum Wimmer & Grab.

3.Cirsium arvense (L.) Scop. var. integrifolium Wimmer & Grab.

4.Cirsium arvense (L.) Scop. var. mite Wimmer & Grab.

5.Cirsium arvense (L.) Scop. var. vestium Wimmer & Grab. (USDA,1999)

1. Eurasia, North Africa (Stubbendiek et al ,1994)

2.Introduced to N.America with earliest French and English colonists, probably as an impurity in agronomic seed (Moore and Frankton,1975)

1.Most of the northern temperate zone (Moore and Frankton,1975)

2.Now found throughout N.America, with the exception of S.E. states (USDA,1999)

3.CanadaDistribution.htp Here

E. Habitat

1.Rangelands and pastures

2.Croplands

3.Roadside ditches, waste areas, disturbed sites (Stubbendiek et al ,1994)

4.often in deep moist soils but will grow in a wide range of soil types (Moore and Frankton,1975)

1.Growth habit

a. Perennial

b. herbaceous forb

c. 0.3-1.2 m tall 

d. reproduces by seed or creeping rhizome (Stubbendiek et al ,1994)

2.Leaves

a. 5-18 cm long, 1.5-6 cm wide 

b. lobes or margins have short spines

c. sessile to petiolate

d. margins lobed to entire

e. leaf surfaces tomentose to hairless (Stubbendiek et al ,1994)

3. Inflorescence

a. flower is pink to purple and sometimes white

b. dioecious but hermaphrodites are occasionally found (Kay,1985)

c. corymb-ish clusters of heads

d. heads formed of involucre with protruding corolla (Stubbendiek et al ,1994)

e. heads roughly ovate-cylindrical ~2.5 cm long (Moore and Frankton,1975)

f. up to 100 heads on a large plant (Bostock and Benton, 1979)

4. Seeds

a. achene 2.5-4mm long, 1-1.5 wide 

b. pappus 1.5-2.5 cm long for wind dispersal

c. achene surrounds 1 small seed (Stubbendiek et al ,1994)

d. achenes weigh 1.8 mg

e. female plants produce ~ 600 achenes/growing season (Bostock and Benton, 1979)

f. seeds exhibit a very low level of innate dormancy, with deep burial longevity may be prolonged (Roberts and Chancellor, 1979)

5. Genetic structure

a. dipoid 2n=34 (Moore and Frankton,1975)

6.Rhizomes

a. fleshy

b. very extensive and fast growing

c. creeping

d. capable of regeneration when severed (Stubbendiek et al ,1994)