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long white hairs, while the leaves are sparse 

 woolly-hairy. Leaf margins are coarsely lobed and 

 like most thistles, spine tipped. Solitary 

 flowering heads occur at the tips of branches, 

 with each head containing 25-50 white to light 

 pink, tubular flowers. Each head is also 

 surrounded by a ring of green bracts (the 

 involucre) tipped by yellow spines. The outer 

 bracts are sharply spine-tipped, while the inner 

 bracts are more lax. Cobwebby hairs connect 

 alternate bracts, and cross over the bract in 

 between to give a lace-like appearance to the 

 involucre (adapted from Schassberger 1991) . 



2. TECHNICAL DESCRIPTION: "Perennial from a taproot, 

 3-7 dm tall, freely branching, the stem crisp- 

 villous to arachnoid-f loccose or rather thinly 

 tomentose, often eventually glabrate; leaves 

 rather thinly f loccose-tomentose beneath, greener 

 and more glabrate above; heads terminating the 

 branches; involucre mostly 17-25 mm high, more or 

 less arachnoid-tomentose, its rather broad bracts 

 contracted into erect or more spreading yellow 

 spines 3-8 mm long, the innermost slender, but 

 innocuous and somewhat twisted; flowers rather 

 pale pink or purplish" (Hitchcock et al. 1955) . 



3. LOCAL FIELD CHARACTERS: Cirsium subniveum differs 

 from C. neomexicanum var. utahense in its smaller 

 and apparently less numerous-flowered heads. 

 Also, the bases of the leaves are decurrent in C. 

 subniveum . and it has a more northern and montane 

 distribution (Hitchcock et al. 1955, Welsh et al . 

 1987) . Cirsium subniveum is distinguished from 

 other species in the genus found in Montana by a 

 number of characters: the presence of long 

 involucral bracts; leaves that are much reduced 

 upward; decurrent wings of lower leaves that are 

 usually longer than those of the uppermost leaves; 

 and involucral bracts that are pubescent with 

 cobwebby hairs that tend to connect alternate 

 bracts, and cross over the bract between (Dorn 

 1984) . 



Due to a faulty camera, only a photograph of a 

 head that contains aging flowers and developing 

 achenes is found in Section VI, p. 36. 



D. GEOGRAPHICAL DISTRIBUTION 



1. RANGE: Cirsium subniveum is known from central 



Idaho to Jackson Hole Wyoming, Montana (Beaverhead 



