BLACK COTTONWOOD.
P. trichocarpa, Hook.
Farther west, covering the mountain slopes from Alaska to Mexico, and liking even better the moist, rich low lands, is the black cottonwood, the giant of the genus, reaching two hundred feet in height, and seven to eight feet in trunk diameter. Tall and stately, it lifts its broad
rounded crown upon heavy upright limbs. In the Yo semite the dark, rich green of these poplar groves along the Merced River makes a rich, velvet margin, glorious when it turns to gold in autumn.