FLOWERING PLANTS AND FERNS OF ARIZONA 903 



11. Solidago occidentalis (Nutt.) Torr. and Gray, Fl. North Amer. 2: 

 226. 1842. 



Euthamia occidentale Nutt., Amer. Phil. Soc. Trans, ser. 2, 7: 

 326. 1840. 



Tuba, Coconino County (Kearney and Peebles 12864), 5,000 feet, 

 September. Alberta to British Columbia, south to New Mexico, 

 northern Arizona, and California. 



18. APLOPAPPUS 62 



Herbs or shrubs; leaves alternate, entire to bipinnatifid; heads small 

 to large, usually radiate, yellow, or the rays rarely saffron color; 

 involucre usually definitely graduated ; achenes cylindric to turbinate ; 

 pappus copious, of graduated capillary bristles. 



Key to the species 



1. Stems strictly herbaceous, but the plants sometimes with a woody caudex. 



(If the stems exceptionally herbaceous in normally woody species (A. heter- 



ophyllusy A. drummondii) , then the heads discoid, turbinate, and the 



leaves usually entire) (2). 



2. Heads discoid; leaves closely serrate, the teeth with white spinescent tips; 



heads campanulate or hemispheric, many-flowered; plant rarely more 



than 25 cm. high 1. A. nuttallii. 



2. Heads radiate (3). 



3. Leaves strongly 3-nerved and veiny, coriaceous, entire; plants with woody 

 branched caudices; stems low, few-leaved; heads usually solitary (4). 

 4. Phyllaries very obtuse to barely acutish, strongly graduate. 



6. A. ARMERIOIDES. 



4. Phyllaries acuminate to acute, usually little graduate- 7. A. acatjlis. 

 3. Leaves not 3-nerved and veiny; plants not with woody branched 



caudices (5). 



5. Leaves entire or rarely with a few teeth, large, the basal ones lanceolate 



to obovate, rarely less than 1.5 cm. wide; phyllaries not spinescent- 

 tipped (6). 

 6. Heads 1 to 3 per stem; disk 1.5 to 2.5 cm. thick; rays usually saffron 

 color; stem loosely pilose above 4. A. croceus. 



6. Heads several or numerous; disk 1 cm. thick or less; rays yellow; 



stem hispidulous above 5. A. parryi. 



5. Leaves sharply serrate to bipinnatifid, the teeth or lobes spinescent- 

 tipped, the basal leaves not large; phyllaries spinescent-tipped (7). 



7. Plant annual; involucre strigose or hirsute, obscurely if at all glandular. 



2. A. gracilis. 

 7. Plant perennial; involucre usually conspicuously glandular or 



tomentose 3. A. spinulosus. 



1. Plants shrubs or undershrubs or, if almost entirely herbaceous (rarely so in 



A. heterophyllus and A. drummondii), then the heads discoid and turbinate (8) 



8. Heads solitary at the tips of the branches, definitely peduncled, radiate, 



large, the disk 1 cm. high or more; involucre broad, the phyllaries about 



3-seriate, not strongly graduated; pappus bright white, about 6 mm. 



long 8. A. LIXEARIFOLIUS. 



8. Heads cymose or panicled or, if solitary, then not definitely peduncled; 

 involucre usually narrow, often strongly graduated; pappus straw- 

 colored or dull whitish or brownish (9). 

 9. Heads usually solitary, leafy-bracted, the proper phyllaries about 2- 

 seriate, subequal, 8 to 11 mm. long; style appendages at least twice as 

 long as the stigmatic portion, acuminate; rays to G; plant densely 

 glandular 9. A. suffruticosus. 



62 Reference: Hall, H. M. the cents ii aplopappus. aphylogeneticstupyinthecompositae. Tar 

 negie Inst. Wash. Pub. 389 : 1-391. 1928. 



