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Pink, Rose, Red, or Purple Flowered Forbs

Pink, Rose, Red & Purple Flowered Forbs
Alfalfa
Black henbane
Blue Mustard
Bull thistle
Canada thistle
Common burdock
Diffuse knapweed
Hounds-tongue
Iberian knapweed
Meadow knapweed
Musk thistle
Purple loosestrife
Purple starthistle
Red clover
Redstem filaree
Russian knapweed
Scotch thistle
Spiny plumeless thistle
Spotted knapweed
Squarrose knapweed
Tall morning-glory
Teasel

 

Bull Thistle
Cirsium vulgare (Savi) Ten. (Aster family, Asteraceae)
 

Description

Stoutly taprooted, coarse, multibranched annual, biennial or short-lived perennial forb, 2 to 6-1/2 feet tall; with stiff, hairy foliage and conspicuous prickly-winged stems.

Leaves: Rosette leaves elliptic to oblanceolate, 4 to 16 inches long; margins deeply coarse-lobed and toothed; main prickles 3/16 to 9/16 inch long; stem leaves smaller, more deeply lobed and spinier; upper surfaces of all leaves green, evenly covered with stiff, sharp- pointed hairs, sometimes sparsely cobwebby; lower surfaces covered with cobwebby hairs; leaf bases extend nearly all the way down stem internodes as conspicuous prickly wings; stems loosely covered with white cobwebby hairs, surfaces glandular.

Flowers: Flowers June to October; purple hemispheric to bell- shaped flower heads 1 to few, 3/4 to 1-1/2 inches in diameter, loosely covered with cobwebby hairs and with at least 1 bract-like leaf just below; purple corollas 1 to 1-3/8 inches long; flower head bracts 1 to 1-1/2 inches long, 3/4 to 1-1/2 inches in diameter lanceolate to linear, spreading to reflexed; spines less than 3/16 inch long, yellowish.

Fruit: Achenes 1/8 to 3/16 inch long, ovate to elliptic, slightly compressed, smooth, glossy, gray or tan; pappus bristles plumose and deciduous, 9/16 to 1-3/16 inches long, white, forming a ring at the base and falling as a unit.

Habitat

Cultivated and disturbed or degraded sites in grassland, woodland, forest, and riparian communities, and roadsides within elevations that generally range from 4,500 to 9,100 feet.

Propagation/Phenology

Reproduces by seed; seeds per flower head range from less than 100 to more than 400.

Comments

Native to Europe; heavy grazing and disturbances that create bare soil patches facilitate seedling establishment and survival. New Mexico Class C noxious weed.

Collage of 4 images of Blue Thistle

 

 

 
Forest Service Shield
Invasive plants and weeds of the national forests and grasslands in the southwestern region
Bull thistle flower heads and stems Bull thistle plant Bull thistle rosette Bull thistle flower heads