C. DESCRIPTION 



GENERAL NONTECHNICAL DESCRIPTION: Cirsium 

 lonqistylum is a perennial herb from thick, woody 

 underground steins (Figure 6) . The stems are 20-24 

 inches tall, ribbed, and lightly covered with 

 long, cobwebby hairs. The basal rosette leaves 

 are somewhat spiny, shallowly lobed, green, 

 hairless above and densely white hairy below. The 

 stem leaves are gray-green with long white 

 cobwebby hairs, narrowly spear-shaped, about 10 

 times as long as wide (up to 6 in. long and % in. 

 wide), and with lobes up to Va the width. The 

 smaller upper leaves are only shallowly lobed with 

 numerous fine marginal spines to h in. long. The 

 flower heads are about \\ in. high and 1 in. wide, 

 and usually in a tight cluster at the top % of the 

 plant. In young plants, the upper part of the 

 stem may be unexpanded and the flowers clustered 

 at the top of the stem. The flower heads have a 

 few small leaves beneath, and the uppermost 

 resemble the involucral bracts in shape. The 

 involucre is \ in. high. The outer bracts are 

 narrowly spear-shaped, less than '/« in. wide at the 

 base, and have a few glands or a dark blotch. 

 The tip is slightly wider with a yellowish ragged 

 margin and has a slender spine less than Ve in. 

 long. The middle and inner involucral bracts are 

 progressively narrower and less ragged at the tip. 

 The flowering head is white. The individual 

 flowers are Vs in. long with a basal ring of 30-40 

 tawny hairs % in. long. The anthers are slightly 

 longer than h. in. The style extends to Ys in. 

 beyond the flower tube. The seeds are \ in. long 

 and less than Va in. wide, light brown and 

 sometimes flecked with purple (Schassberger 1991) . 



TECHNICAL DESCRIPTION: Plant perennial by biennial 

 offsets from stout, woody rhizomes; stems ribbed, 

 50-60 cm tall, to 1.5 cm thick at base, lightly 

 arachnoid pubescent with long multicellular hairs; 

 rosette leaves moderately spiny, margins with 

 broad, shallow divisions, green and glabrous 

 above, densely white pubescent beneath; cauline 

 leaves gray-green, arachnoid pubescent, with 

 multicellular hairs above, white villous (long 

 thin hairs with single long terminal cell and 1- 

 several short basal cells) below, linear- 

 lanceolate, base not decurrent, about 10 times as 

 long as wide, to 15 cm long, 1.5 cm wide, lobed 

 less than or equal to 1/3 the width, smaller upper 

 leaves essentially entire, lobes ovate, often 



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