BUCKWHEAT FAMILY 

 A. Flower-heads peduncled, in terminal umbels. 



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Umbel simple (its rays unbranched, bracted only at base). 

 Bracts at base of umbel in a leafy whorl. 



Leaves rounded, Y% in. or more wide; stems reclin- 

 ing at base 1. E. lobbii. 



Leaves oblanceolate, less than ^ in. wide; stems 



erect 2. E. umbellatum 



Bracts inconspicuous, not leafy. 



Foliage densely matted 3. E. incanum. 



Foliage loose, the stems being more diffuse at base... 4. E. marifolium. 

 Umbel compound (its rays being forked and bracted at 

 about the middle). 



Leaves J /2 in. or more wide 1. E. lobbii. 



Leaves less than J^ in. wide (usually V\ in. or less). 

 Involucres deeply lobed, lobes becoming reflexed; 



leaves lanceolate or spatulate 5. E. stellatutn. 



Involucres with short erect teeth; leaves ovate or 



roundish 6. E. ursinum. 



Flower-heads either sessile along 1 the branches or terminal, 

 never umbellate. 



Perennials with woody base. 



Leaves nearly sessile, white-woolly on both sides 



Heads terminal, mostly solitary 



Heads scattered along the branches 



Leaves long-petioled, green above 



Annual, slender, heads less than J4 in. high 



... 7. E. ovalifolium. 

 ... 8. E. wrightii. 

 ... 9. E. nudum. 

 ... 10. E. virgatum. 



1. E. lobbii T. & G. Flowering stems 3 to 8 in. high, from 

 a little-branched thick base. Leaves thick, oval or roundish, 

 very obtuse, distinctly petioled, J^ to 2 in. long and nearly 

 as wide, white-woolly, often glabrate above. Umbels very 

 pubescent, of 2 to 5 rays only V/ 2 in. or less long. Involucres 

 nearly J4 in. long, the lobes becoming recurved. Flowers 

 rose-color. — Tuolumne Canon, Lundy, and northward, on 

 gravelly slopes. 



2. E. umbellatum Torr. Sulphur Flower. Flowering 

 stems 3 to 12 in. high, from a much- 

 branched woody leafy base. Leaves 

 oblanceolate or oblong, tapering to a 

 petiole, ^ to 1 in. long, white-woolly, 

 often becoming glabrous at least above. 

 Umbels of 3 to 10 stout branches ^ to 2 

 in. long. Involucre-lobes becoming re- 

 flexed. Flowers yellow. 



This low but almost bush-like plant, 

 with numerous yellow heads, is conspicu- 

 ous on stony hillsides at middle alti- 

 tudes, blossoming in July and August. 



