AMONG THE PINES AND FIRS = 207 
with regard to the cultivation of silver fir under 
climatic conditions differing so essentially from 
those of the localities to which it is indigenous. 
Except when grown under very favourable condi- 
tions, its timber, known as ‘ White Pine’ from 
the paucity of resin ducts, ranks rather below 
that of spruce in general quality, and both of 
these are inferior to the heartwood of larch and 
Scots pine. The wood of the Douglas Fir or 
Red Pine of Oregon (P. Douglasii) produced in 
Scotland is now known to rank in quality between 
that of Scots pine and larch, and as its production 
of wood exceeds in annual average that of any 
other conifer grown in Britain, this very valuable 
tree seems to deserve special consideration and 
experimental cultivation in woods worked for 
profit. 
The rate of growth of Douglas fir is indeed 
remarkable. In 1887 evidence was given before 
the Parliamentary Committee on Forestry that 
on the Scone estate, in Perthshire, a plantation of 
eight acres in extent, made in 1860, gave a thin- 
ning of 620 poles of large size in the spring of 
1887. This plantation, as the Earl of Mansfield 
has kindly informed me, now consists of 1535 
