The poplar (Populus trichocarpa), often called balm-of-Gilead from the gum on its buds, is a tall tree, towering above its companions and gracefully embowering the banks of the river.

Its abundant foliage turns bright yellow in the fall, and the Indian-summer sunshine sifts through it in delightful tones over the slow-gliding waters when they are at their lowest ebb.
Some of the involucres of the flowering dogwood measure six to eight inches in diameter, and the whole tree when in flower looks as if covered with snow.

In the spring when the streams are in flood it is the whitest of trees.

In Indian summer the leaves become bright crimson, making a still grander show than the flowers.
The broad-leaved maple and mountain maple are found mostly in the cool canyons at the head of the Valley, spreading their branches in beautiful arches over the foaming streams.
Scattered here and there are a few other trees, mostly small--the mountain mahogany, cherry, chestnut-oak, and laurel.

The California nutmeg (Torreya californica), a handsome evergreen belonging to the yew family, forms small groves near the cascades a mile or two below the foot of the Valley..