PLANTING DISTANCE FOR DOUGLAS FIR. 15 



The estimate covers a very wide area and does not indicate 

 how far any one species may predominate in a particular part 

 of the area, but even where the Douglas fir is strongly 

 predominant it seems to be generally associated with one or 

 more other species. The worst fault of Douglas fir in its early 

 years as a pure crop in this country is a certain tendency 

 towards weakness of root-system, which makes it liable to be 

 swung by the wind and to go down with heavy snow ; perhaps 

 no tree is more sensitive to any injury to its root-system, and 

 less able to make good the damage caused by bad nursery 

 work and bad methods of planting. The young plants may be 

 growing rapidly with every appearance of health and vigour, 

 but if the roots have been turned to one side in the nursery or 

 by careless notching, the tree is very likely to go down before 

 the wind or beneath the snow between the tenth and the 

 twenty-fifth year. 



Even with the best of nursery work and planting, it is 

 doubtful whether the Douglas fir has so much hold on the 

 ground in the earlier stages of its growth as have Sitka spruce, 

 Thuya, Western hemlock, and Abies grandis. The last alone, 

 perhaps, is quite equal to the Douglas fir in the rapidity of its 

 height-growth, and even so its early developmervt is rather 

 slower; the others will succeed in groups and patches, if not as 

 single stems. Where the soil is too moist for Douglas fir, 

 Sitka spruce and Thuya will take its place. 



There is great need for experiment in the formation of mixed 

 woods of Douglas fir and other fast-growing conifers; we have 

 to find out the combination of species which will best resist 

 wind and snow, and we have also to find out to what extent the 

 formation of mixed woods can safeguard the Douglas fir from 

 the risk of extensive damage by fungus disease. 



