GENUS PSEUBOTSUGA. 109 



Scales persistent. 



Bracts long, two or three-pointed. 

 Cotyledo7is varying in number from five to twelve. 

 Leaves stiff, flattish, bright green, and more or less acum- 

 inate. 



Branches whorled ; bark on young shoots glabrous. 



This genus was constructed for the Douglas fir, the habit 

 and foliage being nearly that of the silver firs, and the male 

 flowers like those of Picea. 



PseudotSUgfa Dougrlasii,^ Carriere. The Douglas Fir. 

 (ySynonyvis : Abies taxifolia, Poiret; Pimis taxifolia, Lambert ; 

 Pinus Douglasii, Lambert ; Pseudotsuga taxifolia, Britton ; A bies 

 DouglasUy Lindley ; Picea Douglasii, Link ; Tsuga Douglasii, 

 Carriere.) British Columbia to Colorado, Texas and Mexico. 

 1827. Whether planted singly or in clumps, this tree is highly 

 effective, the giant proportions, easy and graceful outline, and 

 thickly-foliaged branches, of the deepest and richest green, 

 being special points of attraction. Although perfectly hardy 

 everywhere in this country, yet the Douglas fir cannot stand 

 exposure to hard-blowing winds, the leader and upper branches 

 under such conditions suffering greatly, and in many instances 

 becoming almost destitute of foliage. The production of 

 timber goes on at a rapid rate, and in this respect the tree is 

 surpassed by no other grown in this country, fully 5 cubic 

 feet per year having been produced over a period of fifty 

 years. The timber too is of good quality, and the results of 

 numerous experiments which I instituted for the purpose of 

 testing this have been very satisfactory, and will be found in 

 the chapter Timber of Coniferous Trees. When standing 

 alone the tree has a tall, straight, and very gradually tapering 

 trunk, the branches, which are horizontally arranged and de- 

 creasing in length upwards, being retained in a healthy 

 condition down to ground level. The leaves vary in length 



^ A monograph on the Douglas fir, by myself, will be found in the "Transactions 

 of the Royal Scottish Arboricultural wSociety," vol. xi., part ii., 1886. 



