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What its height may originally have been is impossible to say, as it is broken off at about 175 feet. This tree has a very swelling base, which does not show so well as I could wish in the photograph (Plate 227). At the ground it measures 21 paces in circumference. Above the swelling, at about 6½ feet, I made it 41 feet 5 inches in girth. Assuming this tree to be 24 feet in girth at 100 feet high, and to have had a top at all in proportion to its girth, it must have contained 7000 to 8000 cubic feet of timber, or even more. The soil in which it grows is a deep fertile loam, and the timber standing in the valley is some of the finest in the island. Plate 228, from a photograph also taken in Vancouver Island, gives an idea of the forest, and shows on the right the trunk of a typical Douglas Fir; on the left, a trunk of Thuya plicata.

In the eastern part of the Washington Forest Reserve, Mr. Martin W. Gorman found this species up to 6000 feet, and measured a tree growing at 5500 feet, 132 years old, which was 183 inches diameter on the stump, with the bark 3 inches thick. Another tree at 1200 feet elevation, 244 years old, was 43 inches in diameter, with bark 6 inches thick. In the dry region the tree ranges from 70 to 120 feet high and from 20 to 50 inches diameter. He remarks that the species resists fire better than any other conifer of this region, and bears fertile cones at an earlier age than any other, a tree of only twelve years old having well developed cones.

Observations on the rapid growth of Douglas fir at various ages in its own country are given by Mayr.’ In southern Oregon, on the best sandy loam, with a rich humus, he measured Douglas firs 130 feet high at eighty years old; a fallen stem, 100 feet high, contained 135 cubic feet.

The wood of the Douglas fir is known in the European, South African, and Australian markets as Oregon pine or Oregon fir, on the Pacific coast of North America as red fir or yellow fir, in Utah, Idaho, and Colorado as red pine, and in California is sometimes incorrectly called spruce or hemlock. It produces probably a larger quantity of commercial lumber than any other conifer in the new world, or at least on the Pacific coast; and is likely to continue the principal source of supply for most purposes, as the white pine (P. Strobus) of the New England states and Canada, and the long-leaved or pitch pine of the southern states become scarcer; and as its timber is likely in the future to become an important article of trade in Europe, both as an imported and home-grown product, I think it may be useful to give some particulars of the way in which the immense sawmills of Oregon, Washington, and British Columbia are managed.

First, as regards the growth of the timber, Prof. Sheldon, the Oregon State forestry expert, has published in the Oregon Timberman, May 1904, a valuable paper, which entirely confirms my own much more limited observations, and goes to show that the two forms locally known as red and yellow fir are not in any way distinct, but are simply the result of different conditions of growth.

When the trees grow in an open space, and have the annual rings, as is usually the case in youth, pretty far apart, they may attain at the butt 16 to 18 inches diameter at forty years. In such trees the thickness of the sap-wood is from 2 to 3

1 Fremdländ. Wald- u. Parkbäume, 398 (1906).