A New Study of Some Problems Relating to the Giant Trees [pp. 305-316]

Some Problems Relating to the Giant Trees.
tion which forms the floor of the Pavilion at
the Calaveras Grove shows many such inclusions some of them quite extensive-and
reveals very clearly the method of their formation. All growth in these trunks, as was
noted before, proceeds by formation of a
layer of new wood between the old wood and
the bark; this means, of course, that the
bark must be lifted from its place to make
room for the new growth. But the bark in
a recess between two adjacent buttresses is
braced like an arch against its abutments,
and cannot be lifted. Its substance yields
somewhat under increasing pressure, but the
layers of growth at the crown of the arch become thinner and thinner, till they are almost
invisible. The sap, which can no longer gain
entrance here, is forced forward to the point
where the strain is relieved, and is deposited
there in a layer of unusual thickness. The
inner edges of both buttresses thus become
the points of most rapid growth, and gradually fold themselves about the space till they
actually touch. The next ring of wood, then,
is continuous, and seals up all that is within.
The increased growth, meantimtne, has gone
to the nourishment of a new lateral root; a
new buttress is built out beyond the former
vacant space; and presently the old buttresses and their roots are flanked and out of the
race. That this phenomenon is not more
frequently noticed in other trees cannot be,
as I think, because it does not occur. The
thinness and the texture of their bark would,
no doubt, more frequently allow the arch to
give way and crumble under pressure, thus
making the occurrence rarer. But these imprisoned masses, it must be remembered, are
largest below, and are there in actual contact
with the earth at the under surface of the
trunk. Decay would, therefore, in the case
of most trees, effectually remove or disguise
even what had been actually imprisoned, and
so destroy the legibility of the record. It
would not be strange if this were found to be
the origin of internal decay in many old trees.
Here, too, there might be a reasonable explanation of the frequent accounts of living
toads being found imprisoned in the heart
of trees. The animal, in his search for sum
mer quarters, might well enough have crowded himself into such a cavity but a very short
time before he was discovered.
The age of the Sequoias is the one point
most hopelessly befogged to the ordinary
tourist. No amount of inquiry at the Grove
could elicit a syllable of real information
from those who should know, and who really
did know, as I afterwards ascertained. A
count of the annular rings of one of these
trees was made years ago by J. D. Whitney,
of the Geological Survey, and the results
were published in his "Yosemite GuideBook." Professor Gray, too, has made a
study of the rings in a section which was
sent to Cambridge, and in his paper previously referred to, he makes mention of still
another count. But no glimpse of these results was to be had at the Grove. Nor could
I there learn that a single other one of the
thousands of visitors at the Grove had ever
undertaken the simple task of finding out for
himself. The vaporings and idle imaginings
of the newspaper man, I am compelled to
believe, are more acceptable both to landlords and tourists, thain any presentation
of actual facts. Of course, I undertook the
recount of Professor Whitney's tree. It
was a tree of full, though not extreme age,
and it offers greater facilities for accurate determination than any other. The recount, I
may say, was made with every possible precaution to secure absolute accuracy. It was,
in fact, a double count of the opposite ends
or faces of the lowest section of the trunk.
There was nowhere any need of guessing or
estimating, save at the very center, where the
record of some five or six years was obscured
by slivering of the wood. The faces counted
were eighteen feet apart-a distance which
would correspond to a growth of from twelve
to fifteen years, according to circumstances.
The lower face gave 1240 rings, and the upper i226-a perfect tally, as I considered it.
The discrepancy between these results and
Professor Whitney's is very slight. His
count was made at a point higher up on the
tree, and yet his result 1255 years is somewhat greater than my largest number. But
when we consider the nature and purpose of
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