Reports of explorations and surveys, to ascertain the most practicable and economical route for a railroad from the Mississippi River to the Pacific Ocean: Vol. 6, Pt. 3

BOTANY.
the Cascades, at this point, were collected about fifty minor flowering plants, some of peculiar
interest. Of these, 3Jienziesia empetriformis, Saxifraga Tolmcei, and Pentstemon Menziesi, covered large surfaces with their flowers, and, with the gentians, recalled the heaths and other
alpine plants of the Old World.
The Cascade mountains, in the vicinity of the Columbia, are covered with a forest similar in
character to that which I have described, but in which by far the largest number of trees are
Douglas' spruce and the western balsam fir. Here, as on the coast mountains, where the
forests have been burned off, the ground is covered with a rank growth of Pteris aquilina. The
banks of the Columbia, along the water's edge, are lined with cotton-woods, and in some places
with Garry's oak.
The lower part of the Willamette valley is occupied by the densest forest which I saw at the
west, composed principally of Douglas' spruce, here known as the red fir, the western balsam
fir, called by the inhabitants the white fir, the hemlock spruce, and arbor vita. Of dicotyledonous trees almost the only ones are the large leafed maple, the vine maple, (Acer
circinata,) and Cornus Nuttallii. The upper part of the valley consists, for the most part,
of prairie, covered with a luxuriant growth of grass, while the borders of the streams are
lined with oaks, as in the Sacramento valley. The annual vegetation, which is quite varied,
includes a large number of species found in California, with others better suited to a more
northern latitude and a moister climate.
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