80 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 
grow gregariously, and the forest is so dense in places where it 
has not been touched by woodcutters, that it is often hard to 
identify the species. A marked characteristic of these forests is 
the dense growth of dwarfish, creeping bamboo which covers the 
ground, and the number of climbing plants. The latter grow to 
the tops of many of the large trees, and are used for ropes, like 
the rattans of the Himalaya and the tropics. 
The forests of the Pacific coast of North America are probably 
the only ones in the temperate regions of the world which 
contain a great reserve of large timber suitable for export; 
and of the trees which constitute this reserve, the Douglas 
fir is by far the most important. Though not equalling 
Sequoia gigantea in girth, it probably surpasses every other tree, 
except perhaps S. sempervirens, in height, trees of 250 to 300 
feet being common in the forests of British Columbia and 
Washington. Here the climate is moist, and the soil often very 
deep and good, so that the trees have advantages which they 
cannot have in Scotland. The timber which is cut for export 
comes from selected trees of not less than 200 years old, and 
often much more, and the rate of growth depends on the 
density of the crop when young. I doubt whether we can 
hope to produce timber equal to it in size or quality, because 
we so rarely find soil good enough to keep the trees growing 
sufficiently densely to clean their trunks; and even if such 
places be planted, really fine timber cannot be expected in 
less than 150 to 200 years,! and this is too long a period for 
most planters in Europe to wait for a return. What the value 
of the thinnings may be is, as yet, somewhat uncertain; but 
from what I have seen in the best plantations in Scotland 
and England, I doubt whether this item would equal in value 
that obtainable from larch thinnings off an equal area of 
similar land. The different varieties of Douglas fir seem to be 
but little understood in Britain at present. It is supposed that 
there are two well-marked forms, which are sold as “Oregon” 
and ‘“‘ Colorado” respectively. The latter we know to be a much 
slower-growing tree than the Pacific coast form, though hardier. 
1 A rotation of 150 to 200 years for conifers in Britain seems quite out of the 
question. From 40 or 50 to 60 or 70 years will probably prove the usual 
limits for growing such timber-crops on business principles. And as the 
celebrated plantation of Douglas fir (at Taymount, near Scone) was worth 
nearly £200 an acre at 40 years of age (1900), the wood-merchant who then 
offered 9d. a cubic foot for the whole crop could hardly have thought the timber 
of inferior quality. —Hon, ED. 
a 
