FLOWERING PLANTS AND FERNS OF ARIZONA 1007 



14. Leaves much narrower, not palmate-nerved, not evidently reticu- 

 late (15). 

 15. Phyllaries 8, broad, blunt, with a conspicuous, usually bright yellow 

 margin; plant a shrub, with narrowly lance-linear leaves taper- 

 ing to the base 15. 8. SALIGNUS. 



15. Phyllaries more numerous, narrow, usually acute or acuminate; 

 plants herbaceous or suffrutescent (16). 

 16. Leaves conspicuously clasping; plants not tomentose (17). 



17. Plant denselv glandular-pubescent 16. S. parryi. 



17. Plant glabrous (18). 



18. Plant annual; heads disciform or discoid; leaves oblong or 



oblong-ovate, 2 to 6 cm. long 17. S. mohavensis. 



18. Plant perennial; heads conspicuously radiate; leaves usually 



larger (19). 



19. Leaves oblong, the middle ones 20 to 25 cm. long, 4 to 6.5 



cm. wide, closely repand-denticulate; plant herbaceous, 



simple below the inflorescence. . .18. S. huachucanus. 



19. Leaves lanceolate or linear, 4 to 10 (17) cm. long, rarely 



more than 1.5 cm. wide, irregularly dentate, chiefly 



toward the base; plant suffrutescent, branched. 



19. S. LEMMONT. 

 16. Leaves not clasping, or, if so (sometimes in S. cynthioides) , then 

 the lower leaves tomentose beneath (20). 



20. Plant glabrous and somewhat glaucous 20. S. wootoxii. 



20. Plant tomentose, at least at the base of the stem (21). 



21. Heads solitary (very rarely 2 or 3), large, the involucre 10 to 

 12 mm. high; basal leaves obovate, crenate-toothed ; stem 

 leaves few, small, narrow, entire, bractlike. 



21. S. ACTINELLA. 



21. Heads several or many (rarely solitary in S. werneriaefolius 

 and S. neomexicanus) , smaller (22). 

 22. Basal leaves ovate, 2 to 5.5 cm. wide, often subcordate, 

 closely dentate or dentate-serrate _ 22. S. arizoxicus. 

 22. Basal leaves linear-oblanceolate to obovate, usually much 

 narrower, if as broad, then not closelv dentate-ser- 

 rate (23). 

 23. Involucre persistently tomentose, at least toward the 

 base; plant low, rarely more than 20 cm. high; stem 

 naked or with 1 or 2 narrowly subulate bracts. 



23. S. W^ERNERIAEFOLIUS. 



23. Involucre glabrous or soon glabrate; plants usually 

 taller; stems more or less leafy (24). 

 24. Basal leaves elliptic, oval, or obovate, finely and closely 

 crenate-serrate or serrate; tomentum mostly fuga- 

 cious 24. S. HARTIANUS. 



24. Basal leaves otherwise; tomentum more persistent (25) . 

 25. Basal and stem leaves essentially similar, nar- 

 rowly oblanceolate (about 5 to 12 cm. long, 

 4 to 10 mm. wide), entire to remotely toothed, 

 green and glabrescent or glabrate above, gray- 

 tomentulose beneath; stem almost uniformly 



leafy throughout 25. S. cynthioides. 



25. Basal and stem leaves usually dissimilar, at least the 

 basal ones normally broader, often sharply 

 toothed; stem usually with much reduced leaves 

 above 26. S. neomexicaxus. 



1. Senecio spartioides Torr. and Gray, Fl. North Amer. 2: 438. 1843. 



Northern Navajo County, Coconino County, and Hualpai Mountain 

 (Mohave County), 6,500 to 9,200 feet, openings in pine forests, 

 July to October. Nebraska and Wyoming, south to Texas and 

 Arizona. 



Broom groundsel. The plant is known to be poisonous to livestock, 

 but is rarely eaten. 



286744° — 42 64 



