170 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



10. Quercus oblongifolia Torr. in Sitgreaves, Rep. Zuiii & Colo. 173. 1853. 

 Type locality: "Western New Mexico." Arizona was a part of New Mexico at 



this time and, as the expedition started from what is now extreme western New 

 Mexico, this locality must have been in western Arizona. 



Range: Western and southern Arizona, southeastern California, southwestern New 

 Mexico, and adjacent Sonora. 



New Mexico: Dog Spring; Guadalupe Canyon. Mountains, in the Upper Sonoran 

 Zone. 



This species has frequently been confused with Q. undulata, Q. grisea, and Q. ari-' 

 zonica. The characters used in the key will separate these species at once. This is 

 not at all closely related to the first-named species, but very near the other two. When 

 mature it is a low, spreading tree of the live-oak type with oblong leaves which are 

 wholly glabrous, as are the young twigs. 



11. Quercus grisea Liebm. Overs. Dansk. Vid. Selsk. Forh. 1854: 171. 1854. 

 Quercus undulata grisea Engelm. Trans. Acad. St. Louis 3: 393. 1877. 



Type locality: "Texas. Nov. Mexico pr. el Paso." The type is Wright's 665 from 

 western Texas. 



Range: Western Texas, New Mexico, southeastern Arizona, and adjacent Mexico. 



New Mexico: Sandia Mountains; Santa Clara Canyon; Magdalena Mountains; 

 Bear Mountain; Florida Mountains; near Hermosa; Organ Mountains; Guadalupe 

 Mountains; White Mountains; Llano Estacado; San Luis Mountains; Kingston; Burro 

 Mountains. Drier, rocky foothills of the mountains, in the Upper Sonoran Zone. 



New Mexico seems to be the region in which Q. grisea and Q. arizonica meet, the 

 former coming in from Texas and the latter from Arizona. They are closely related 

 species, possibly too closely for convenient separation, but there are slight differences 

 in the general form of the trees, hard to describe but moderately easy to see, and the 

 acorns are noticeably different. 



Generally speaking, Q. grisea is a low scrubby tree (young ones which do not yet 

 bear forming much of the scrub oak of the lower slopes of the mountains in the southern 

 part of the State), small groups of which growing in open canyons or on slopes fre- 

 quently give the impression of an old apple orchard. Q. arizonica is usually a larger 

 tree, though never with a very tall trunk. It is commonly much branched from 

 near the base and wide spreading. 



Quercus grisea is variously confused by different authors with Q. undulata, a low 

 shrub of the mountains of northern New Mexico and southern Colorado, and with 

 Q. oblongi/olia, a tree from farther west. 



Quercus grisea X emoryi. 



A large, round-topped tree with dark gray trunk and limbs, and slender young 

 twigs with dense, yellowish, stellate pubescence; young leaves yellowish green, 

 becoming gray-green and glabrous above; most of the leaves oblong, entire, some with 

 a few coarse, spinulose teeth, their texture subcoriaceous, thinner than in either of 

 the species; young fruit with the cup of Q. grisea. 



Collected on the Rio Frisco near Lone Pine, in 1904, by E. 0. Wooton (no. 3115). 

 This may prove to be a new species, rather than a hybrid. 



12. Quercus arizonica Sarg. Gard. & For. 8: 92. 1895. Arizona oak. 

 Type locality: Southern Arizona. 



Range : Southern New Mexico and Arizona and adjacent Mexico. 



New Mexico: Santa Clara Canyon; Mogollon Mountains; Bear Mountain; Black 

 Range; Burro Mountains; Big Hatchet Mountains; San Luis Mountains; Lordsburg; 

 Animas Mountains; Organ Mountains; Oscuro Mountains; Capitan Mountains; White 

 Mountains. Lower parts of drier mountains, in the Upper Sonoran Zone. 



This and Q. grisea are the common live oak trees of the drier and lower mountains 

 of the southern part of the State. They are commonly found among the rocks and 



