792 COMPOSITAE (COMPOSITE FAMILY) 



tapering into winged petioles, partly sheathing at the base, sparsely serrulate or 

 entire, the uppermost 3-8 cm. long ; racemes much crowded and oppressed in 

 a dense wand-like panicle; involucre 4-6 mm. long, its bracts linear-oblong; 

 rays 5-6, small. Bogs and wet shores, Nfd. to Keewatin, s. to Minn., Pa., and 

 in the mts. to N. C. July-early Sept. 



20. S. specibsa Nutt. Stem stout, 0.6-2 m. high, smooth below, often 

 roughish above ; leaves thickish, smooth, with rough margins, oval or ovct'-. 

 slightly serrate ; the uppermost 2-4 cm. long, oblong-lanceolate ; the lower 1.5-3 

 dm. long, 5-10 cm. wide, contracted into a margined petiole ; he<ls somewhat 

 crowded in numerous erect racemes, forming an ample pyramidal or tli'/rsiform 

 panicle ; peduncles and pedicels rough-hairy ; involucre cylindric, often gluti- 

 nous, 4.5-6 mm. long, its firm bracts oblong; rays about 5, large. Dry open 

 woods and thickets, local, Mass, to Minn., and south w. Sept., Oct. 



Var. angustata T. & G. Lower, rarely 1 m. high ; leaves lanceolate to ovate- 

 lanceolate, more nearly uniform, the lower 8-12 cm. long. 2-3 cm. wide ; 

 inflorescence usually smaller. (S. rigidiuscula Porter.) Dry open ground, 



0. to S. Dak., and south w. Aug.-Oct. 



= = Heads paniculate, in mostly spreading or recuroed-ascending secund 



clusters. 



a. Leaves fleshy ; plant maritime. 



21. S. sempeYvirens L. Smooth and stout, 0.3-2.5 in. high ; leaves entire, 

 lanceolate, slightly clasping; the lower ones lanceolate-oblong, 1.5-0 dm. long, 

 obscurely triple-nerved ; the uppermost 4-15 cm. long ; racemes short, in an 

 open or contracted panicle ; involucre 4-6 mm. long, many-flowered ; rays showy 

 7-10. Salt marshes, or rocks on the shore, Gulf of St. Lawrence, and south w., 

 Aug.-Nov. (rarely Dec.). Varies, in less brackish swamps, to forms with 

 thinner elongated linear-lanceolate leaves tapering to each end, and more erect 

 racemes in a more slender panicle. 



b. Leaves not fleshy ; plants not maritime. 



1. Basal leaves long-petioled, conspicuously larger than the 10-30 (-40) remote 



or subremote cauline ones. 



o Stems strongly angled; leaves shagreen-scabrous on the upper surface ; hemh 



lb-2Q-flowered. 



22. S. patula Muhl. Stem sharply 4-angled, smooth, 0.5-2 in. high ; lower 

 leaves 1-4 dm. long, ovate, acute, serrate, pale, very smooth and vein;/ under- 

 neath, but the upper surface very rough, like shagreen ; uppermost leaves lanceo- 

 late, 2-5 cm. long; racemes rather short and numerous on the leafy-bracted 

 spreading branches ; heads rather large and full ; the involucre 3-4.5 mm. Ion-, 

 nearly as broad, its linear-oblong bracts obtuse. Bogs and swamps, chiefly in 

 calcareous regions, w. Me. to Ont., and south w. Aug., Sept. 



oo Stems terete or nearly so; leaves smooth or stnoothixh (rarely scabrous") ; 

 heads <>-lb(-2ty-flowered. 



4- Leaves mostly serrate, the lower and middle cauline (as well as the bnxal] 

 rather abruptly narrowed to the petiolar base. (Extreme forms .t x. 

 ulmifolia might be sought here.) 



23. S. arguta Ait. Smooth; stem (J-15 dm. high, obscurely angled above; 

 leaves usually thin, sharply double-serrate ; the lower ovate or ovate-lanceolate, 

 1.5-4 dm. long, pointed at both ends, their petioles margined; the upper 

 elliptiral-limreolate, 3-9 dm. long; ract-ntm /(/<< >it. .spn'tiding. r//.s-/<o.W in 

 an elongate open panicle ; involucre about 4 mm. long. \\*thin />mr(s blnntish ; 

 rays 6-1, large; achenes glabrous. Open woods and thickets, w. Me. to Ont., 

 and south vv. Aug., Sept. 



24. S. Bo6ttii Hook. Smooth, or scabrous-pubescent or below hirsute, 

 slender, often branched, 0.6-1.5 m. high ; leaves rather finely serrate, ovate to 

 oblong-lanceolate, pointed ; the lower 6-15 cm. long ; the upper small, oblong to 

 narrowly lanceolate, often entire ; heads loosely racemose at the tips of the very 



