183 



shoots and short leaf-stems downy, as is also the under surface of the leaves ; mostly 

 smooth above. AcQrns sessile, or on short stems, oblont?, f to 1 inch long, and nearly 

 ■^ an inch in diameter ; cups hemispherical, -} inch broad ; scales tuberculate. 



71.— Black Oak. "Mountain Oak." {Quercus Emoryi^Torrey.) 



A tree 40 to 50 feet in height aud 1 to 3 feet in diameter, or a shrnb 

 at the eastern limit of its range; it occurs abundantly through the 

 mountain ranges of southern New Mexico (eastern and southern Ari- 

 zona, and western Texas) at elevations between 5,000 and 7,000 feet; 

 rarely if ever found on hills or far from streams, preferring the fine 

 gravelly or sandy soil of open canyons. The wood is very heavy and 

 brittle, of a poor quality, and little esteemed, except for fuel, the large 

 trees often becoming hollow or otherwise defective. 



Description. — Leaves thick, f to 2^ inches long, ^ to li inches wide, ovate, qb- 

 long-ovate, often approaching halberd-shape, with an acute point, and chiefly (some- 

 times rounded or with strongly) heart-shaped base; margin entire, but mostly wavy, 

 with distant, shallow or rather large prickle-poiuted teeth; mature leaves usually 

 dark glossy green both sides; when young minutely downy, as are the young shoots 

 and short leaf-stems, but the latter more densely so. Acorns mostly sessile — some- 

 times with short stem— ovate, with a rather sharp and prolonged point, | to | of an 

 inch long, and f of an inch in diameter; cup hemispherical, ^ inch broad, with close, 

 smooth scales. Acorns abundant, sweet, edible. A tree with a scraggy appearance, 



72. — {Quercus hypoleuca, Engelmann.) 



A small but very handsome tree with ev^ergreen foliage, found in the 

 high mountain ranges of southwestern New Mexico, Santa Eita Mount- 

 ains, southeastern Arizona (southward into Sonora, and in the Limpia 

 Mountains of Texas), at elevations above 6,000 feet, usually preferring 

 rocky or gravelly sites in deep canyons and valleys. Commonly 15 to 

 20, occasionally 50, feet in height, with a diameter of 2 feet; the 

 trunks usually large for the height. The wood is heavy, very hard, and 

 strong, but large-sized trees are often defective. In localities where it 

 can be grown it would be a popular ornamental tree. 



Description. — Leaves thick, commonlj^ 2 to 3| inches long and f to 1 inch wide, 

 lance-shaped, with rounded, slightly heart-shaped or acute base, the upper end usually 

 tapering to a long thin point; margin rolled down, entire, or wavy, with few indistinct 

 or shallow teeth — sometimes sharply toothed ; young leaves downy above, always 

 densely woolly below, but with age becoming smooth and dark green above; stems 

 downy. Acorns usually sessile or sometimes with short stems, ovate, | to f of an 

 inch long; cups hemispherical, with thin, downy scales. Trunk and branches gener- 

 ally gnarled and twisted. 



73.— Canoe BiEOH. White Bmcn. Paper Biech. [Betula papyrifera* 



Marshall.) 



A rather large tree, growing chiefly in rich woodlands and along water- 

 courses, and extending farther north than any other American decidu- 

 ous tree. It has a limited range in the Eocky Mountains region, being 



* See Dwarf Birch in list of shrubs, page 196. 



