AMERICAN FOREST TREES 219 



where it covers the hillsides and occurs in canyons at altitudes from 

 5,000 to 10,000 feet above sea level. It occasionally ascends nearly or 

 quite to the summits of the highest peaks. The form of the tree varies 

 greatly, as might be expected from a range extending from one to two 

 miles above sea level. On the dry, windswept summits the tree degener- 

 ates into a shrub, with stiff, harsh branches. Lower down, in canyons 

 and in other situations where moisture may be had and the soil is fertile, 

 trunks are fifty or sixty feet high and three or four in diameter; but these 

 are not the usual sizes even in the best of the tree's range, for it cannot 

 be classed as a timber tree. 



The hardships of the desert have stunted it, and its form is rough. 

 It is important for fuel, and this has been its chief use. The region 

 where it occurs is thinly settled, and demand for lumber is small, but 

 stockmen build corrals and fences to enclose sheep and cattle, and the 

 Arizona white oak supplies some of the rough poles and posts for that 

 purpose. The wood is heavy, hard, strong, and the heartwood is almost 

 black, but the sapwood is lighter. The grain and figure of the wood are 

 not attractive, and what little may be sawed into lumber in the future 

 will be rather low-grade. The branches are crooked and when cut into 

 cordwood the ricks are so open that it is a common saying in the region 

 that "you can throw a dog through." The wood burns well, and the 

 demand for fuel is large, in proportion to the population of the country. 



The leaves of this oak are sometimes slightly lobed, and are some- 

 times nearly as smooth as willow leaves. They are light red and covered 

 with hair when they unfold in the spring, but when mature they are 

 dark green, and shiny. Acorns are one inch or less in length, and 

 rather slender. They are very bitter, and wild animals are inclined 

 to let them alone, unless pressed by hunger, and then eat them sparingly. 

 This insures good reproduction, provided other conditions are favorable. 

 Though cordwood cutters may strip the large trees from the hills and 

 canyons, scrub growth may be expected to continue, particularly on 

 high mountains, and in ravines where roads cannot be built. 



NETLEAF OAK (Quercus reticulata) will never attract lumbermen in this country, 

 but sometime they may send to the Sierra Madre mountains of Mexico to procure it. 

 In that region it is a tree large enough for lumber; but the portion of its range over- 

 lapping on the United States lies in southern Arizona and New Mexico among 

 mountains from 7,000 to 10,000 feet above sea level. Conditions are unfavorable 

 and the netleaf oak shows it by its stunted size and rough form. The wood is hard, 

 heavy, dark brown in color, with lighter sapwood. The medullary rays are numerous 

 and very broad. The tree seldom exceeds forty feet in height and one foot in diam- 

 eter. The leaf is netted somewhat like that of the elm. The acorn is usually not 

 more than half an inch in length. 



ROCKY MOUNTAIN OAK (Quercus undulata) bears acorns which may be eaten 

 like chestnuts, and not much more may be said for the tree in the way of usefulness 



