" In a
former paper, he said, he endeavored to show that, in the unfavorable
season of 1879, the growth of wood of all kinds of trees was materially
less than in the comparatively favorable season of 1878. He had now to
state results of measurements of the same trees for the recent favorable
season of 1880. The previous autumn was unfavorable for the ripening of
young wood, and the trees in an unprepared condition were exposed during
a great part of December, 1879, to an asperity of climate unprecedented
in this latitude. This might have led one to expect a falling off in the
growth of wood, and it appeared, from comparison of measurements, that,
with very few exceptions, the growth of wood last year was even more
below the average of favorable years than that of the bad year, 1879.
Thus, in fifteen leaf-shedding trees of various species, exclusive of
the oak, the average growth of trunk girth in three successive years
was: 1878, 8-10ths; 1879, 45-100ths; 1880, 3-10ths and a half. In
four specimens of the oak tribe, the growth was: 1878, 8-10ths; 1879,
77-100ths; 1880, 54-100ths. In twenty specimens of the evergreen
Pinaceae the growth was: 1878, 8-10ths; 1879, 7-10ths; 1880, 6-10ths and
a half. After giving details in regard to particular trees, Sir Robert
stated, as general deductions from his observations, that leaf-shedding
trees, exclusive of the oak, suffered most; that the evergreen Pinaceae
suffered least; and that there was some power of resistance on the part
of the oak tribe which was remarkable, the power of resistance of the
Hungary oak being particularly deserving of attention.
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