T. Kisx.—On New Zealand Beeches. 808 
period as five or six years, even when the timber has been apparently sound 
and good at the first. How far this may be due to its being cut during the 
period of active growth, or to its having been used while in a green con- 
dition, both practices being the rule rather than the exception, it is impossible 
for me to say. Another possible cause of its early decay in certain cases 
may be its having grown upon wet ground. It must be admitted at least 
that its durability cannot have been fairly tested in the majority of cases. 
But making all possible allowances on these points I am compelled to place 
its good properties considerably below those of the tooth-leaved beech. 
In the Oxford Forest it is sparingly mixed with white pine, miro, and 
matai, the last decidedly rare. A few fine trees run up to from 60 to 75 feet 
in height, but the bulk do not exceed 40 feet in the clear trunk. The 
manager of one of the largest sawmills informed me that “trunks capable 
of giving 4-14 feet lengths were extremely rare.” I learned that the tree 
' was termed “red birch,” ** brown birch,” “ white birch,” “ black birch,” 
and “ yellow birch,” at different stages of its growth, but the application of 
these terms varied greatly: perhaps ‘black birch” was most generally 
applied to the mature condition before decay commenced, and “ white bireh" 
to the young state; but there were too many exceptions to allow of the 
names being other than misleading. 
Unripe trees of this kind never afford durable timber, however large 
their dimensions; unless the tree is allowed to stand for a few years after 
attaining its full growth decay speedily commences. The time required for 
ripening, at present undetermined, cannot be very long, and when once the 
process is completed decay sets in very quickly, and progresses with greater 
or less rapidity. Sometimes it commences at the heart before full growth 
has been attained ; the trunk appears perfectly sound, but on being squared 
or sawn its defective condition is exhibited at the expense of the woodman. 
All our beeches are more or less subject to this peculiarity, but I am in- 
clined to believe that the period between the ripening of the wood and the 
commencement of decay is unusually short in the entire-leaved beech, and 
as the timber is of but little value at any other period, we have here one 
cause of its frequent early decay after conversion. 
In this species the medullary rays of fully ripened timber are more 
durable than the wood formed by the fibro-vascular bundles of the annual 
cylinder. Logs decaying in the forest often present a curious appearance 
from this cause: after the sapwood has perished the outer surface of the 
heart-wood appears to be divided into numerous short lamine running 
longitudinally. These lamine project more or less beyond the general mass 
owing to the early decay of the wood of the cylinder. If the log has been 
kept from the ground, the appearance is still more remarkable, the medullary 
