25 6 ASTER FAMILY 



y. Leaves 1-2 in. long, lobes 1 in. or more 



long; heads round, 1 mm. wide A.filifolia 



b. Stems herbaceous, occasionally woody at the 

 base 



(1) Leaves entire or coarsely 3-5-lobed 



(a) Leaves entire, linear, green; involucres 



green, 2-3 mm. wide; heads many in 



a long panicle A. dracunculoides 



(b) Leaves entire to coarsely and irregular- 



ly 3-5-lobed, felted on both faces, or 

 green above ; involucres white or gray, 

 felted, woolly or hairy A. ludowciana 



(2) Leaves, at least the lower, regularly 5-7- 



lobed or pinnatifid to finely dissected 

 (a) Long woolly hairs between the flowers ; 



leaves usually gray-hairy 

 x. Heads many, 3-5 mm. wide; leaves 

 short, finely dissected; stems 6-18 in. 

 high, usually mat-like; at 3-9000 ft. A.friglda 

 y. Heads 1 to about 10, 5-12 mm. wide, 

 often nodding; leaves longer, pinnati- 

 fid; stems 1-10 in. high, clustered or 

 single; at 10-13000 ft. A.scopulorum 



(b). No long woolly hairs between the flow- 

 ers of the head 



x. Leaves smooth, green at least above 

 (x) Stems from a caudex or woody base 

 m. Leaf segments linear to thread- 

 like A. canadensis 

 n. Leaf segments broad, lanceolate to 



oblong 

 (m) Leaves mostly 1 -pinnatifid ; 



heads 20-30-flowered A. discolor 



(n) Leaves mostly 2-pinnatifid ; 



heads 30-40 flowered A. franserioides 



(y) Stems merely from a tap root, bien- 

 nial; leaf segments toothed as a 

 rule A. biennls 



y. Leaves more or less gray-hairy 



(x) Heads many in a large panicle A. canadensis 



