168 PACIFIC STATES FLORAL CONGRESS. 



3. Quercus undulata. Turrey, 1828. ROCKY MOUNTAIN OAK. 

 This, the easternmost of our western oaks, is found abundantly on 



the eastern foothills of the Eocky Mountains, forming thickets of 

 vigorous stolons or traveling sprouts 2 to 3 feet high, extending to Utah 

 and southern Nevada, southward to New Mexico and 'Arizona, where 

 it becomes trees 20 to 30 feet high. Known by its small, wavy, often 

 spinescent leaves. Quite variable, some of its forms receiving distinct 

 names; as, Q. pungens, Q. Fendleri, Q. grisea, and Q. turbinella. Dis- 

 covered by Dr. Edwin James, botanist of Major Long's expedition to 

 explore Rocky Mountains. The doctor's rich collection included also the 

 Rocky Mountain white pine, Piniis flexilis. 



4. Quercus Gambelii. Nuttall, 1848. GAHBEL OAK. 



Another of the small oaks of the Rocky Mountains, extending west- 

 ward to the Wasatch Mountains, of Utah, thence southward in larger 

 forms to New Mexico and Arizona, on the summits of mountains. Dis- 

 tinguished by its large dark green and deeply-lobed leaves, and its dark 

 gray, deeply-fissured bark. Discovered 1844, on the banks of the Rio 

 Grande, by Wm. Gambel, an early student with Nuttall, and botanist 

 of a party that explored largely in the southwest. He joined Capt. 

 disaster of imprisonment by an early snowfall in a pass of the Sierra. 

 Boone's party of gold seekers, 1849, and shared with them in the fatal 



Sargent regards Greene's Q. venustula as belonging here, a beautiful 

 shrub with less-lobed leaves and very small acorns, on mountains of 

 southern Colorado and northern New Mexico. 



5. Quercus reticulata. H. & B., 1807. NET-LEAF OAK. 



One of the large trees of Mexico, 20 to 30 feet high, that extends in 

 smaller forms into Arizona and New Mexico, as a very showy shrub on 

 high elevations. At once detected by its oblong or nearly round, thick, 

 leathery leaves, which are strongly net-veined beneath, and its generally, 

 many-fruited spikes of fruit, 1 to 5 inches long. American specimens 

 first discovered 1874, on Mt, Graham, 9,500 feet altitude, in northern 

 Arizona, by Dr. J. T. Rothrock, and soon after by other explorers, includ- 

 ing the writer, on same mountain and on Santa Catalina, Santa Rita, 

 Chirricahua, and Huachuca Mountains. This pretty oak would be a 

 prize if it could be cultivated, and experiments should be made to 

 determine. 



6. Quercus hypoleuca. Engelm, 1876. WHITE-LEAF OAK. 



Another beautiful black oak of Mexico, inhabiting, also, the moun- 

 tains of Arizona and New Mexico south of the Colorado plateau, where 

 it becomes a tree 20 to 40 feet high. Distinguished by its lanceolate, 

 thick leaves, which are densely clothed beneath with short, white hairs, 

 the veins prominent, often reddish. Discovered 1851, by Charles Wright, 

 ene of the most successful botanists of the Mexican Boundary Survey. 



