FLOWERING PLANTS AND FERNS OF ARIZONA 1005 



No specimens from Arizona have been examined, except some 

 possibly from that State labeled Arizona {Palmer in 1877), but the 

 known range of the species is such that its occurrence in Arizona is 

 practically certain. 



114. C AC ALIA. Indian-plantain 



Herbaceous perennial, about 1 m. high, woolly-tufted at base, 

 otherwise nearly glabrous; leaves mostly in a basal tuft, broad, long- 

 petioled, 3- or 4-pinnatisect into linear or lance-linear ultimate divi- 

 sions, the stem leaves few, the upper ones much reduced; heads 

 numerous, small, discoid, white, 5- to 7-flowered, in a dense terminal 

 corymbiform panicle; phyllaries 5 or 6, less than half as long as the 

 flowers; achenes glabrous; pappus of numerous capillary bristles. 



1. Cacalia decomposita A. Gray, PL Wright. 2: 99. 1853. 



Willow Spring (southern Apache County), Chiricahua andHuachuca 

 Mountains (Cochise County), Patagonia Mountains (Santa Cruz 

 County), 5,000 to 8,000 feet, rich shaded soil, July to September. 

 Southeastern Arizona, southwestern New Mexico, and Sonora. 



115. TETRADYMIA. Horsebrush 



Shrub, 1 m. high or less, stiffly much-branched, canescent- 

 tomentose throughout; leaves oblanceolate to linear, entire, sessile, 

 callous-tipped, usually less than 1.5 cm. long, often with axillary 

 fascicles; heads medium-sized, discoid, 4-flowered, yellow, clustered 

 at the tips of the branches; involucre of 4 equal thick-chartaceous 

 phyllaries, tomentose outside; achenes obovoid, densely silky-pilose; 

 pappus of copious, whitish, capillary bristles. 



1. Tetradymia canescens DC, Prodr. 6: 440. 1837. 



Navajo County to eastern Mohave County, 6,000 to 7,000 feet. 

 dry open ground, in sandy or rocky, sometimes saline soil, often 

 abundant, July to September. Montana to New Mexico, northern 

 Arizona, and California. 



The only form occurring in Arizona is var. inermis (Nutt.) A. Gray. 

 The plant is said to be browsed locally by sheep, but its forage 

 value is low and it is suspected of being poisonous. The Hopi are 

 reported to use the leaves and roots as a tonic and for uterine dis- 

 orders. White-haired animals eating this plant are reported to 

 suffer photosensitization of the skin, resulting in severe dermatitis. 



Tetradymia axillaris A. Nels. (T. longispina (M. E. Jones) Rydb.) has been 

 listed from Arizona by various authors, but no material from the State has been 

 seen by the writer. It can be distinguished readily by its long straight spines 

 (transformed primary leaves), 5 or 6 phyllaries, and 5- to 9-flowered heads. 



116. SENECIO. 11 Groundsel 



Herbs or shrubs; leaves alternate, entire to once or twice pinnatifid; 

 heads medium-sized or rather large, yellow, radiate or discoid; invo- 

 lucre essentially 1 -seriate, of equal, usually narrow, subherbaceous 

 phyllaries, often with a calyculus of shorter bractlets at base; achenes 

 glabrous or pubescent; pappus of soft white capillary bristles. 



11 Reference: Greenman, J. M. monograph of the north and central American species ok the 

 GENUS SENECIO, PART II. Mo. Bot . Card. Ann. 2: 573-026. 1915: 3: 86-194. 1916: 4: 15 36 

 1917; 5: 37-108. 1918. (Not et completed.) 



