FLOWERING PLANTS AND FERNS OF ARIZONA 557 



1. Rhamnus crocea Nutt. ex Torr. and Gray, Fl. North Amer. 1: 261 . 



1838. 



Southern Coconino County and Hualpai Mountain (Mohave 

 County), south to Cochise and Pima Counties, 3,000 to 6,800 feet, 

 common in chaparral and in open coniferous forest, March to May 

 (rarely October). Arizona, California, and Baja California. 



Kedberry buckthorn. A handsome shrub, with bright-green 

 holly like leaves and bright-red fruits, attaining a height of 4 m. (13 

 feet) in California, but perhaps never so large in Arizona. The Ari- 

 zona form is the hollyleaf buckthorn, var. ilicifolia (Kellogg) Greene 

 (R. ilicifolia Kellogg). It is browsed by deer and bighorns. The 

 Apache Indians ate the fruits with meat. 



2. Rhamnus californica Esch., Acad. Imp. Sci. St. Petersb. Mem. 



10: 285. 1823. 



Southern Coconino County and Hualpai Mountain (Mohave Coun- 

 ty), to Cochise and Pima Counties, 3,500 to 6,500 feet, common in 

 chaparral and open coniferous forests, May and June. New Mexico 

 and Arizona to southern Oregon, California, and Baja California. 



California buckthorn, coffeeberry, pigeonberry. Sometimes 

 attaining a height of 5.5 m. (18 feet), but usually smaller. The Arizona 

 form is var. ursina (Greene) Wolf (R. ursina Greene). R. Humeri 

 Greene (type from the Cliiricahua Mountains, Blumer 1290, in part) 

 is thought by Wolf to be a hybrid between this variety and R. betulae- 

 jolia Greene. 



3. Rhamnus betulaefolia Greene, Pittonia 3: 16. 1896. 

 Southern Apache County to Cochise County, 5,500 to 7,500 feet, 



mostly along streams in the live oak and yellow pine belts, May and 

 June. New Mexico, eastern Arizona, and northern Mexico. 



Birchleaf buckthorn. Usually a smaller shrub than R. californica, 

 reaching a height of 2.5 m. (8 feet). The typical form is limited in 

 Arizona to the southeastern part. A form occurring in the northern 

 part of the State is var. obovata Kearney and Peebles, the type of which 

 was collected on Navajo Mountain, Coconino County (Peebles and 

 Sm ith 13930). It is found also on the north rim of the Grand Canyon 

 (Eastwood 6001, Eastv:ood and Howell 989). This variety extends into 

 southern Utah and Nevada and is well separated, geographically, from 

 the main area of R. betulaefolia. 



4. CEANOTHUS 



Much-branched shrubs with commonly rigid or spinescent branches; 

 leaves alternate or opposite, the blades entire or dentate, conspicuously 

 veined; flowers perfect, with hooded, long-clawed petals, in cymose 

 panicles; calyx adnate to the lower part of the ovary; fruit a 3-celled 

 capsule. 



These plants afford good browse for cattle, sheep, and especially for 

 deer. They are esteemed as honey plants. It is reported that an 

 infusion of the bark of C. integerrimxis, and perhaps other species occur- 

 ring in Arizona, has been employed as a tonic and that the flowers 

 form a lather in water. Many species of this genus are cultivated as 

 ornamentals, and are often known as wild-lilac. The seeds are dis- 

 charged with considerable force when the capsules open. 



