294 ASTER FAMILY 



y. Stems and leaves white-woolly only 

 when young, typically green and 

 smooth at flowering ; leaves variously 

 toothed to pinnatifid, more rarely 

 entire, round, oblong or lanceolate to 

 spatulate; heads sometimes without 

 rays, the latter yellow to orange-red S\ aureus 



Solidago Linne 1753 Goldenrod 

 (Lat. solidus, whole, -ago, like, from its former use in medicine) 



PL 38, fig. 1. 

 Heads with yellow pistillate ray-flowers, disk-flowers yellow, mostly 

 perfect, achenes round or angled, usually ribbed, pappus of hair-like 

 bristles ; receptacle flat or convex, without chaff, involucre oblong to bell- 

 shaped, the bracts imbricated in several rows ; heads in terminal axillary 

 panicles, corymbs, cymes, etc.; leaves alternate, simple; perennial. 



1. Heads in a flat-topped spreading cluster 



a. Rays fewer than the disk flowers, 1-10 



(1) Heads 8-10 mm. high, 30-40-flowered ; 



rays 7-10 ; leaves ovate to oblong, very 



rough S. rigid a 



(2) Heads 6-8 mm. high, 5-8-flowered ; rays 



1-3 ; leaves linear or lance-linear S. pumila 



b. Rays more numerous than the disk flowers, 12- 



20; heads 4-6 mm. high, disk flowers 8-14; 



leaves linear or lance-linear 3\ lanceoldta 



2. Heads in a terminal cone-like, or a raceme-, spike- 



or head-like cluster, which is not flat-topped 

 a. Stems and leaves smooth or nearly so 



(1) Leaves distinctly 3-veined 



(a) Stems 4-15 in. high; stem leaves ob- 



lanceolate to linear ; in dry soil 5\ missouriensis 



(b) Stems 1-5 ft. high; stem leaves lanceo- 



late ; along streams S. serotina 



(2) Leaves not 3-veined 



(a) Stems 2-4 ft. high; heads 3-4 mm. wide, 



very many in a much branched pan- 

 icle-like cluster ; at 4-7000 ft. 5. speciosa 



(b) Stems 1 in. -2 ft. high ; heads 5-7 mm. 



wide, mostly few in a compact head- 

 or raceme-like cluster; at 7-13000 ft. 



