FLOWERING PLANTS AND FERNS OF ARIZONA 559 



Deerbrush. Rated in California as one of the most valuable browse 

 plants for livestock. Although widely distributed in Arizona, it is 

 nowhere abundant in this State. It is the handsomest species, with 

 large bright-green leaves and feathery panicles of whitish flowers. 

 The shrubs reach a height of about 2.5 m. (8 feet) but are usually 

 smaller. 



3. Ceanothus martini M. E. Jones, Contrib. West. Bot. 8: 41. 1898. 

 Coconino County, Big Springs, Kaibab Plateau (Eggleston 10210), 



Grand Canyon below the north rim (Goodding in 1935), about 7,500 

 feet, June. Utah, Nevada, and northern Arizona. 



4. Ceanothus fendleri A. Gray, Amer. Acad. Arts and Sci. Mem. ser. 



2, 4: 29. 1849. 



Throughout the State except the extremely desert portions, 5,000 

 to 10,000 feet, very common in pine forests, tending to form low 

 thickets, April to October. South Dakota to New Mexico and 

 Arizona. 



Buckbrush. Its great abundance gives this plant outstanding 

 importance as browse for livestock and deer. It is more spinescent 

 than the other Arizona species, seldom more than 1 m. (3 feet) tall 

 and at high altitudes often less than 0.5 m. About equally abundant 

 and widely distributed are: (1) The more typical form, with leaf 

 blades thin, sparsely pubescent or glabrate above, and not very prom- 

 inently veined; and (2) var. venosus TreL, with leaf blades thicker, 

 permanently sericeous above, and very prominently veined. The two 

 forms intergrade freely. 



5. COLUBRINA 



A shrub with divaricate, subspinescent branches; leaves alternate* 

 petioled, the blades entire or denticulate, oval or obovate, pinnately 

 few-veined ; flowers axillary, solitary or in small fascicles, inconspicuous, 

 greenish or yellowish; petals present, hooded, short-clawed; calyx 

 adnate to the lower part of the ovary; fruit a 3-celled drupelike capsule. 



1. Colubrina calif ornica Johnston, Calif. Acad. Sci. Proc. ser. 4, 12: 

 1085. 1924. 



Eastern Maricopa County, Pinal County, and southern Yuma 

 County, 3,000 feet or lower, dry slopes and in washes, June to Au- 

 gust. Southwestern Arizona, southeastern California, and Baja 

 California. 



In favorable situations the plants are 3 m. (10 feet) high but are 

 usually smaller. The Arizona specimens have smaller fruits than 

 those from the type locality in Baja California. 



72. VITACEAE. Grape family 



Stems woody, climbing or trailing, with prominent nodes and usually 

 with tendrils; leaves alternate, simple or compound, with long petiolrs 

 dilated at base; flowers small, greenish, perfect or unisexual, in cymose 

 panicles, 4- or 5-merous, often with a disk; stamens opposite the 

 petals; fruit berry like; seeds bony. 



The cultivated grapes are the only economically very important 

 members of this family. 



286744° — 42 36 



