COMPOSITAE (THISTLE FAMILY) 



10 EUTHAMIA. 

 i a Irregular flowers 12-20; leaves linear-lanceolate, 3-5- 



nerved BUSHY GOLDEN-ROD. (E. graminifolia.) 



b Irregular flowers 6-12; leaves narrowly linear, usually 

 i-nerved 



SLENDER FRAGRANT GOLDEN-ROD. (E. carollniana.) 

 n BfiLLIS GARDEN DAISY. (B. perennis*) 



12 BOLT6NIA ASTER-LIKE BOLTONIA. (B. asteroides.) 



13 SERICOCARPUS. 

 i a Leaves linear 



NARROW-LEAVED WHITE-TOPPED ASTER. (S. linifblius.) 

 b Leaves lanceolate to obovate 



TOOTHED WHITE-TOPPED ASTER. (S. asteroides.) 



14 ASTER. 



1 a Some or all of lower and basal leaves petioled and 



heart-shaped at base 2 



b Lower leaves more or less tapering at the base or else 



sessile 12 



2 a Ray flowers white 3 



b Ray flowers blue or violet 7 



3 a Leaves smooth above. WHITE WOOD ASTER. (A. divaricatus.) 

 b Leaves noticeably rough above 4 



4 a Branches of the corymb with glandular hairs 



LARGE-LEAVED ASTER. (A. macrophyllus.) 

 b Branches of the corymb or panicle not with glandular 



hairs 5 



5 a Ray flowers about 6; heads in a rounded corymb 



BERNHARDI'S ASTER. (A. glomeratus.) 

 b Ray flowers 10-20; heads in a flat-topped corymb or 



panicle 6 



6 a Basal sinus of the basal leaves more or less rectangular; 



heads in a corymb SCHREBER'S ASTER. (A. schreberi.) 



b Basal sinus of basal leaves rounded ; heads in a panicle 



BLUE WOOD ASTER. (A. cordifblius.) 



7 a Branches of the inflorescence with glandular hairs 



LARGE-LEAVED ASTER. (A. macrophyllus). 

 b Branches of the inflorescence not with glandular hairs. . 8 



8 a Stem leaves with winged petioles spreading and clasp- 



ing at the base WAVY-LEAF ASTER. (A. undulatus.) 



b Stem leaves sessile or with slender petioles sometimes 



winged but not clasping at the base 9 



9 a Bracts of the involucre spreading, not appressed, pointed 



at the apex ARROW-LEAVED ASTER. (A. sagittifblius.) 



b Bracts of the involucre appressed, usually not pointed 



at apex 10 



10 a Heads in corymbs. . .WHITE WOOD ASTER. (A. di-varicatus.) 

 b Heads in panicles 1 1 



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