ng the ten years following. Any yield figures
for an even-aged forest show a similar jump at the point where the
stand as a whole reaches the determined minimum merchantable size.
For the same reason these hemlock figures are not very far less
promising than those given for fir, for at corresponding ages the
latter include 12 and 13-inch trees and all trees are considered
merchantable to a top diameter of 8 inches.

SPRUCE

Since no systematic study of Sitka spruce second growth has been
made, it can only be predicted from knowledge of its habits that
while in favorable situation it will yield as heavily as Douglas
fir, in other localities its growth in early life is slower and
less regular, making it less likely to produce a good crop before
the carrying charges become burdensome. If this proves true, taxation
rates and land values will be extremely important factors, offset
to some degree by a smaller fire hazard and the probability of
high stumpage.

REDWOOD

For redwood we also lack good figures for any considerable range of
conditions and ages, for redwood growth which followed burns does
not exist and there are no very old cuttings. Government studies
on the northern California coast prove conclusively, however, that
this is our most rapid growing native commercial tree. In thirty
years, in fair soil, it will produce a tree of 16 inches diameter,
80 feet high, and some existing 45-year stands run 20 to 30 inches
on the stump and about 100 feet high. Reckoning 14-inch trees as
merchantable, to be used to 10 inches in the tops, a 25 to 30-year
second growth after logging near Crescent City was found to have
2-1/2 M feet to the acre and the future increase should be very
rapid. There is little question of the profit of growing redwood,
provided the difficulties described elsewhere of getting a dense
crop started are overcome.

PROFITABLE THINNINGS

In addition to the yield of saw timber to be expected when the
second crop reaches manufacturing size, there will be a market
in many cases for material obtained by thinning. It is perfectly
fair to compound for the remainder of the rotation any net profit
so obtained and to set it against the carrying charges. In many
cases it will go far to turn an apparently losing investment into
a very profitable one. Moreover, the proper thinning of growing
stands not only utilizes material which would otherwise die and
be lost before the main harvest, but actually improves