30 
BOTANY OP THE ROUTE. 
but is less than a foot in diameter, and I believe of no especial value as timber. The berries 
have violent cathartic properties, and, though eaten greedily by bears, are not used by the 
Indians as food. 
A birch (B. occidentals ?) is said to be common north of the straits, but I did not meet with 
it. A low, shrubby species, east of the Cascade mountains, exudes from its branches a bitter 
resinous substance, (B. glandulosa.) 
SHRUBBY UNDERGROWTH. 
To complete the description of the forests, I must notice briefly the numerous shrubs which 
constitute an almost impassable underbrush in most parts of them, and are nearly all of use 
either for their wood or fruits. In their distribution they are even more local than the trees, 
and different groups characterize very fully the districts into which the forests are divisible. 
East of the mountains I have remarked that a peculiar group takes the place of forests on the 
Great Plains. There is also another group belonging to the Rocky mountain forests which 
grow along the higher river banks, but, not being in a good condition during my visit there, do 
not appear in the list of plants collected, though I identified the following species among them: 
Rhus diversiloba, Torr. & Gray ; Crataegus sanguinea, Pall ., and another species, Cerasus 
Virginiana?; Rosa cinnamomea, Linn.) Ribes Aureum, (a fine yellow currant;) R. cereum ; 
Clematis LiGUSTiciEFOLiA, NuttaU. 
The hazel, (Corylus Americana,) red cornel, or “willow,” (Cornus Drummondii,) and bar¬ 
berry, are also found on both sides of this range. This latter shrub, absurdly called * 1 Oregon 
grape,” (Berberis aquifolium, the “holly leaved barberry,”) extends west to the Coast range 
only. It produces a blue berry, eatable when cooked, and is much cultivated in the Atlantic 
States as an ornamental plant. This, with a spiraea, (S. arle folia,) a ceanothus, (C. Oregonus, ) 
and the hazel, form most of the underbrush of the “fir” forests between the Cascade and 
Coast ranges. A “mock orange” is also common from the Columbia to Puget Sound, (Phila- 
delphus.) Three species of raspberry are also found, mostly in this region, (Rubus Nutkanus, 
leucodermis, and macropetalus,) but to some extent also west of the Coast range. Three 
species of gooseberry have similar limits, though they do not grow in the shade of forests. 
(Ribes divaricatum, niveum ?, and sanguineum,) and a peculiar rose is found only on the borders 
of the fir forest, (Rosa gymnocarpa.) On Whidby’s island are found two shrubs of much 
interest on account of their locality, Shepherdia Canadensis and a Rhododendron, closely 
resembling R. maximum, but perhaps distinct, which extends along the Cascade range into 
southern Oregon.— (Dr. Newberry.) 
Near Steilacoom, and in other scattered localities, some of the shrubs belonging to the 
Rocky mountain group are occasionally found, (Rhus, Ceanothus velutinus, Oreophila myrti- 
folia.) On the dry prairie two shrubs are met with—the service berry (Amelanchier Cana¬ 
densis, var.l alnifolia) of the northern group, and an elder (Sambucus glauca) which belongs 
to the plains. In the adjoining forests, and often very near it, grows its northern representa¬ 
tive, (S. pubens, var. ?) meeting it here just as it does the allied elder of the Atlantic States 
near New York. Of the shrubs more characteristic of the black spruce forests, but which 
occur also on the higher and moister parts of the Cascade range, many are evergreen, giving 
these gloomy forests an undergrowth of almost tropical appearance, though belonging to alpine or 
boreal families of plants. They do not generally obstruct these forests so much as the pre¬ 
ceding group, and, except close to the ocean, they can be easily penetrated along the uplands. 
