GENERAL PAPERS 139 
Leave the train in southern Arizona and the explorer may 
pass through a different society of plants, a different associa- 
tion of birds, reptiles and rodents every half hour through the 
day. With plants the Yuccas will probably be the main feature, 
near the tracks, and may be a low growing species, or tall, or 
both. Something happens with soil or drainage perhaps and 
the next society along the trail will be a thicket of mesquite 
or cat-claw no larger than gooseberry bushes, or it may be 
a forest of the same with trunks from one foot to five in 
diameter, and ninety feet in the diameter of shade. Then a 
meadow perhaps where the haymakers with mowing ma- 
chines gather profitably a wild harvest. As suddenly a wide 
belt of creosote brush may cover the ground. The mesas 
slanting down from the base of the mountains have the great 
collections of Cacti and of many families. The base of the 
mountain itself is the home of the Agaves, perhaps the low 
growing forms of but a few inches in height, or the larger 
with a flower stalk of thirty feet and one hundred pounds of 
bloom. Perhaps half a dozen species, low and tall, and here 
too, the giant cactus, occasionally sixty feet in height, with 
forty branches. The ferns have their beginning here also 
with perhaps half a dozen species, the societies changing in 
the ascent to the peak as rapidly as the desert vegetation has 
changed below them. Cheilanthes Wrightw the first and Pteris 
aquilinum of the western form, the last. 
These mountains from the railways may seem mere hills of 
naked clay, but if from eight to ten thousand feet above the 
sea they are heavily forested. At the base the Desert willow, 
cotton wood and sycamore hug the streams, with junipers, 
pinyons and manzanita on the hill sides. The madrone, wal- 
nut, oak with a shade perhaps of one hundred feet, and alders 
as high, appear in the next zone and then, last of all, the yellow 
pine, Douglass fir, blue spruce, a dozen or more cone bearers 
in all. Here in fact is the ideal forest, with trunks eight feet 
in diameter and branches one hundred feet above, so dense 
the sun is a stranger. 
In no public park have I seen the equal of the natural park 
effects in the canyons, along the river banks and upon the 
table lands at high altitudes. But the changing order does not 
end with mere elevation. The south side of a mountain is 
unlike the north side; the east side of a canyon has a different 
