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wind. All attempts to grow this tree into timber on bare, exposed, or barren downs and hillsides will, I believe, prove futile.?

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. Ina 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? 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.

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).