Pseudotsuga 825 



wind. All attempts to grow this tree into timber on bare, exposed, or barren 

 downs and hillsides will, I believe, prove futile. 1 



The Colorado or glaucous variety has been so much spoken of, and is recognised 

 so universally in cultivation as a distinct form, that we must speak of its peculiarities 

 in full. It is usually supposed to be known by its colour, which is variable in all 

 races of the tree ; and I know of a case in which colour alone was considered by 

 a forestry expert, to be sufficient to condemn as seed-bearing parents, a large 

 number of vigorous healthy trees of great size, which were certainly of Pacific coast 

 origin. 



The Rocky Mountain forms, of which the Colorado one may be taken as typical, 

 are constitutionally able to endure a continental climate ; namely, one characterised by 

 extremes of summer heat and winter cold ; whilst the coast form is less hardy, 

 though it will endure the extremes of climate in most parts of Great Britain, and 

 is a very much larger, faster-growing, and, from a forester's point of view, more 

 valuable tree. 



They are at Colesborne equally liable to suffer from late spring frost after 

 growth has commenced ; but Mayr, whose experience of both is considerable, says 

 that the Colorado form in Germany, does not suffer like the other, from the 

 freezing of the immature shoots in autumn and early winter ; and wherever this is a 

 common cause of injury to the coast form, the mountain form should be tried instead. 

 Such places, however, are rare in England ; and on this subject I cannot do better 

 than quote the opinion of Mr. Crozier. In a letter to me he says, "That there are 

 two well-defined forms no one with practical experience of the tree will deny, but 

 whether that known as ' Colorado ' is confined to the state of that name seems 

 doubtful. As a timber tree, however, my experience convinces me that in the 

 north of Scotland at least it is a failure, and whatever advantages it may possess 

 over the Oregon variety in its nursery stages, is really of no moment, as after a 

 trial of between thirty and forty years, under the most favourable conditions of soil, 

 shelter, etc., it has failed to make timber on this estate; while the Oregon variety, 

 under much less favourable conditions, has never failed to make good headway. 

 The cone 2 also differs from that of the Oregon variety in some important respects, 

 being much smaller, with the bracts a great deal longer and reflexed." 



" I made a further experiment with this tree some years ago, and may give you 

 the dimensions of average specimens at the present time of Oregon and Colorado 

 Douglas and Norway spruce, grown under exactly similar conditions side by side. 

 The age of the Colorado Douglas and Norway spruce is twelve years, while the 

 Oregon Douglas is ten years from sowing. 



Height. Three last years' growth. Girth at 6 inches high. 



Oregon Douglas 15 feet 6 inches 8 feet 10 inches 9J inches 



Colorado Douglas 10 11 5.-5 .. i 



s P ruce 8 10 ,, 4 5 5 



1 According to Mr. Bean, in Kew Bulletin, 1906, p. 268, this species is used as a hedge plant at Monzie Castle, and 

 answers the purpose very well, being dense and well-furnished. 



2 The cones on cultivated trees are very variable. Cf. Gard. Chron. xxviii. 12 (1900). 



IV Q 



