ced. The wider the ancient
glacier, the wider the corresponding gap in the sequoia belt.
Finally, pursuing my investigations across the basins of the Kaweah
and Tule, I discovered that the sequoia belt attained its greatest
development just where, owing to the topographical peculiarities of the
region, the ground had been best protected from the main ice-rivers that
continued to pour past from the summit fountains long after the smaller
local glaciers had been melted.
Taking now a general view of the belt, beginning at the south we see
that the majestic ancient glaciers were shed off right and left down the
valleys of Kern and Kings Rivers by the lofty protective spurs outspread
embracingly above the warm sequoia-filled basins of the Kaweah and Tule.
Then, next northward, occurs the wide sequoia-less channel, or basin of
the ancient San Joaquin and sings River mer de glace; then the warm,
protected spots of Fresno and Mariposa groves; then the sequoia-less
channel of the ancient Merced glacier; next the warm, sheltered ground
of the Merced and Tuolumne groves; then the sequoia-less channel of the
grand ancient mer de glace of the Tuolumne and Stanislaus; then the
warm old ground of the Calaveras and Stanislaus groves. It appears,
therefore, that just where, at a certain period in the history of the
Sierra, the glaciers were not, there the sequoia is, and just where the
glaciers were, there the sequoia is not.
But although all the observed phenomena bearing on the post-glacial
history of this colossal tree point to the conclusion that it never was
more widely distributed on the Sierra since the close of the glacial
epoch; that its present forests are scarcely past prime, if, indeed,
they have reached prime; that the post-glacial day of the species
is probably not half done; yet, when from a wider outlook the vast
antiquity of the genus is considered, and its ancient richness in
species and individuals,--comparing our Sierra Giant and Sequoia
sempervirens of the Coast Range, the only other living species of
sequoia, with the twelve fossil species already discovered and described
by Heer and Lesquereux, some of which flourished over vast areas in the
Arctic regions and in Europe and our own territories, during tertiary
and cretaceous times--then, indeed, it becomes plain that our two
surviving species, restricted to narrow belts within the limits of
California, are mere remnants of the genus, both as to species and
i
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