OAKS OF PACIFIC SLOPE. 167 



The writer collected specimens of this species near the locality of 

 the Weeping Spruce, 1887, but a sudden storm of rain prevented their 

 preservation. Prof. Brown named this oak in honor of John Sadler, 

 born 1837, in Scotland, an associate of Prof. Balfour, and in 1862 

 secretary of the' Arboricultural Society of Scotland. He traveled ex- 

 tensively, and made many discoveries of new stations of plants in Great 

 Britain. 



12. Quercus dumosa. Nutt, 1842. SCRUB OAK. 



An intricately-branched shrub with stout stems, forming dense 

 thickets, or in canons, becoming tree-like, very variable, and several 

 forms have received other names. Western slopes of Sierra Nevada, 

 common south of San Francisco to San Bernardino Mountains, and on 

 the Channel Islands, where it attains its largest size. Var. revoluta, 

 Sargent, is the form common north of San Francisco. 



This shrub oak, with Brewer's and Sadler's, comprise the small spe- 

 cies of oak in California, and complete the number of 12 species of oak 

 found in California and northward. 



SOUTHERN OAKS. 



MOSTLY IN ARIZONA AND NEW MEXICO. 



1. Quercus Emoryi. Torrey, 1848. EMORY OAK. 



The most abundant oak in Arizona and vicinity, forming a large 

 part of the open forests on the mountain-sides. On low ground becom- 

 ing a tree 30 to 80 feet high, diminishing to low, scraggy bushes at upper 

 limits. Distinguished by its dark brown bark (which caused it to be 

 at first classed with the black oaks), its rigid branchlets, dark green, 

 oblong, acute, leathery leaves, and its small, narrow, sweet acorns, called 

 by the Mexicans "Biotes," and gathered in great quantities for food. 

 Discovered, 1846, by Col. W. H. Emory, commanding a government 

 exploring expedition across the continent from Santa Fe to San Diego, 

 collecting 160 species of plants, including this, one of the most, beautiful 

 and useful oaks of the region. 



2. Quercus oblongifolia. Torrey, 1853. EVERGREEN OAK. 

 Another oak of nearly the same range, especially south of the great 



plateau of Colorado. Recognized by its pale checkered bark, round com- 

 pact head, and light blue foliage. In favorable situations becoming 

 trees 20 to 30 feet high. At lower stations it mingles with the dark 

 Emory oak in pleasing contrast. Discovered 1851, by Dr. S. W. Wood- 

 house, botanist of Capt. Sitgreaves' expedition to the Zuni and Colorado 

 Rivers. Dr. Woodhouse collected animals as well as plants, making 

 a valuable collection preserved in Smithsonian Institute. 



