150 THE ANDES OF SOUTHERN PERU 



sunny slopes have a forest cover; the shady slopes are treeless. 

 At the lower edge of the grassland, only the shady slopes are for- 

 ested (Fig. 53B). Cacti of arboreal size and form grow on the 

 lofty mountains far above the limits of the true forest ; they also 

 appear at 3,000 feet in modified form, large, rank, soft-spined, and 

 in dense stands on the semi-arid valley floors below the dry timber 

 line. Large tracts between 8,000 and 10,000 feet are covered with 

 a forest growth distributed by species — here a dense stand of one 

 type of tree, there another. This is the most accessible part of 

 the Peruvian forest and along the larger valleys it is utilized to 

 some extent. The number of species is more limited, however, and 

 the best timber trees are lower down. Though often referred to 

 as jungle, the lowlier growths at the upper edge of the forest zone 

 have no resemblance to the true jungle that crowds the lowland 

 forest. They are merely an undergrowth, generally open, though 

 in some places dense. They are nowhere more dense than many 

 examples from New England or the West. 



Where deep valleys occur near the border of the mountains 

 there is a semi-arid climate below and a wet climate above, with a 

 correspondingly greater number of species within short distances 

 of each other. This is a far more varied forest than at the upper 

 edge of the timber zone or down on the monotonous plains. It 

 has a higher intrinsic value than any other. That part of it be- 

 tween the Pongo and Yavero (1,200 to 4,000 feet) is very beauti- 

 ful, with little undergrowth except a light ground-cover of ferns. 

 The trees are from 40 to 100 feet in height with an average 

 diameter of about 15 inches. It would yield from 3,000 to 5,000 

 board feet per acre exclusive of the palms. There are very few 

 vines suspended from the forest crown and the trunks run clear 

 from 30 to 60 feet above the ground. Were there plenty of labor 

 and a good transportation line, these stands would have high eco- 

 nomic value. Among the most noteworthy trees are the soft white 

 cedar, strong and light ; the amarillo and the sumbayllo, very dura- 

 ble in water ; the black nogal, and the black balsam, straight and 

 easy to work; the heavy yunquero, which turns pink when dry; 

 the chunta or black palm, so hard and straight and easy to split 



