320 A MANUAL OF FORESTRY. 



a height-growth of about 10 inches on an annual average, 

 or about one-half of that in the coast districts. Under 

 any circumstances, as far as experience goes at present, 

 the Douglas Fir, if planted in suitable localities, out- 

 grows all European timber trees. 



The tree also attains a great diameter ; the average 

 diameter of mature trees, 200 feet high, in the coast 

 districts is given as about 6 feet, and in Montana as 

 about 2 J feet. 



It follows that the volume- increment is very great. 

 Experience up to date shows that it exceeds the fastest 

 growing of European trees to a considerable extent. 



c. Reproductive Power. 



Little is known about this, beyond that the trees 

 grown in Britain produce seed freely, which has been 

 used for rearing the younger plantations. In its natural 

 home it frequently commences bearing seed when 10 

 years old. 



d. Character and Composition of Woods. 



Douglas Fir, grown in crowded woods, produces a 

 complete dense cover overhead, and seems well adapted 

 to be grown in pure woods ; as far as can be judged at 

 present, it is likely to maintain a complete leaf-canopy to 

 a sufficiently advanced age to produce large-sized timber. 

 It is, however, liable to suffer from storms in Britain, and 

 at any rate the leading shoots are always injured, unless 

 the tree is grown in a thoroughly sheltered position. 



Under these circumstances the best results will pro- 

 bably be obtained by mixing it with other species. As it 



