2(1). Plants 5 dm. tall or more, erect, branched only above; stem below glabrous 



or hirsute; leaves mostly entire or merely toothed 



1. M. Boltoniae. 



2. Plants usually about 3 dm. tall or less, diffusely branched from the base; stem 

 glandular-hispidulous throughout, usually also somewhat pilose; 

 leaves mostly laciniate-pinnatifid with spinescent-tipped lobes, 

 sometimes merely toothed 2. M. Coulteri. 



1. Machaeranthera Boltoniae (Greene) Turner & Home. 



Annual taprooted herb, erect and nearly simple below, to 1 m. tall or more, 

 with glandular-pubescence above or glabrate; leaves essentially entire, oblanceo- 

 late to linear, reduced above, with appressed hairs or glabrate; heads solitary, 

 not crowded; involucre hemispheric, 5-10 mm. across, 3-5 mm. high; phyllaries 

 0.75-1 mm. broad; flowers 75 to 100 per head (fewer in late-flowering heads); 

 disk yellow and pappus present; rays light-blue or violet-blue to white, never 

 yellow, (4-) 5-7 mm. long; pappus of ray flowers absent; achenes 2-2.4 mm. 

 long. Psilactis asteroides Gray, P. lepta Shinners. 



Infrequent in alluvial sandy soil, in marshes, river bottoms and along roadsides, 

 in the Tex. Trans-Pecos (El Paso, Hudspeth and Presidio cos.), through N.M. 

 (widespread) to Ariz. (Navajo and Coconino, s. to Cochise and Pinal cos.), June- 

 Nov.; Ariz., N.M., Tex., s.e. to Michoac. and Pue. 



2. Machaeranthera Coulteri (Gray) Turner & Home. 



Divaricately branching throughout, 5-30 cm. tall, stipitate-glandular through- 

 out and usually hispidulous or pilose; leaves oblong to oblanceolate, mostly lacini- 

 ate-pinnatifid with the teeth spinescent-tipped; lower petiolate leaves 2-3 cm. 

 long; upper leaves closely sessile and appressed, becoming much-reduced, some- 

 times entire; involucre about 4 mm. high; phyllaries oblong-lanceolate, acute, 

 granular-glanduliferous except on the whitish chartaceous basal portion; rays 20 

 to 35, white to lavender, about 5 mm. long; achenes pubescent. Psilactis Coulteri 

 Gray. 



In wet or dry saline soils and about playa lakes, in Ariz. (Maricopa, Pinal, Pima 

 and Yuma cos.), Mar.-June; also Nev., Calif, and Son. 



3. Machaeranthera phyllocephala (DC.) Shinners. Camphor daisy. 



Aromatic often glutinous annual herb, sometimes living over one winter, either 

 erect or near the coast usually prostrate, freely branched especially near the 

 base; leaves usually oblanceolate to narrowly obovate, firm or even fleshy, 15-50 

 mm. long, on each side with 5 to 8 prominent salient teeth or short lobes, only 

 slightly reduced toward the head, crowded even up to the base of the head; heads 

 solitary; involucre 9-11 mm. high, hemispherical; phyllaries in about 3 series, 

 not much-graduated, the largest ones in any mature head 1.3-1.7 mm. broad, 

 the tip-region often of a different texture from the base being more herbaceous 

 and sometimes spreading; disk and rays yellow; style branch appendages sub- 

 clavate, shorter and thicker than the stigmatic portion; pappus of ray and disk 

 similar; achene columnar, thick, about 2 mm. long, slightly compressed to plump 

 and subcylindric, fuzzy with whitish ascending pubescence. Haplopappus phyl- 

 locephalus DC, H. rubiginosus T. & G., Eriocarpum megacephalum Nash. 



Abundant in subsaline wet areas near the Tex. coast, s.e. Tex. and Rio Grande 

 Plains, spring-fall; coastal areas. La. to Tam. 



Represented by another variety in the highlands of Mexico. 



10. Solidago L. Goldenrod 



Rhizomatous perennials; rhizomes sometimes short and forming merely a crown 

 or sometimes extensively creeping; aerial stems usually long and slender, ascending 



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