Douglas References Lewis & Clark

Mountain Ridge Covered by Conifers

along the Blackfoot River, Montana

mountain valley with beaver ponds

© 2000 by James L. Reveal

Douglas-fir, Pseudotsuga menziesii

very tall and straight evergreen trees without many lower limbs

© 2000 by James L. Reveal

We conclude the combined text of the two Douglas manuscripts treating Douglas-fir as published in Appendix VIII of Douglas' Journal. Some additional notes and comments are added:

The mountains of the Grand Rapids of the Columbia, situated in Lat. 46° [Cascade Range], are clothed to the top, some peaks of which exceed 5000 feet above the level of the sea. On the Blue Mountains [northeastern Oregon] of the interior it is also found, and clothes also the subalpine range or base of Mount Hood [Oregon], Mount St. Helens, Mount Baker [both in Washington], and Mount Vancouver [British Columbia] as well as the western base of the Rocky Mountains in 52°7'9 N Lat., 115° N Long. [sic], where it maintains a place, and arrives at a considerable size at an altitude of 9000 feet above the level of the sea, 1000 from the verge of perpetual snow.17 It is not a little surprising the vast change of climate and of soil experienced between the western and eastern base of the last-mentioned ridge [the Rocky Mountains along the British Columbia and Alberta border] in the same parallel of latitude, and is beautifully exemplified by the growth of the present tree as well as other of the same tribe [e.g., the genus Pinus as defined in the broad sense of Linnaeus]. On the west side it is enormously large [var. menziesii], on the east a low scrubby tree [var. glauca], and without the recesses of the mountains on the same side it ceases to exist. Being an inhabitant of a country nearly in the same parallel of Latitude with Great Britain, where the winter (even judging from the immense covering afforded it by Nature in its bark) is more severe, gives every reason to hope that it is in every respect well calculated to endure our [e.g., English] climate and that it will prove a beautiful acquisition to English Sylva if not an important addition to the number of useful timbers.18 The wood may be found very useful for a variety of domestic purposes; the young slender ones exceedingly well adapted for making ladders and scaffold poles, not being liable to cast; the larger timber for more important purposes; while at the same time the rosin may be found deserving attention. In the memorable journey of Lewis and Clarke (p. 455)19, in their interesting account of the timber of that country, we find that they "measured some 42 feet in circumference, at a point beyond the reach of an ordinary man. This trunk for the distance of two hundred feet was destitute of limbs; the tree was perfectly sound, and, at a moderate calculation, its size may be estimated at three hundred feet." I am most willing to bear testimony to the correctness of their statement as respects the girth of the timber, but after a two years' residence, during which time I measured any tree that appeared from its magnitude as interesting, I was unable to find any from actual measurement exceedingly the height I have mentioned.20

Douglas-fir in the coastal ranges of northwestern California. I am unable to gather from their description whether the largest mentioned by them can be the same as the present. It would appear not, for in the fifth species mentioned we find that they mention (p. 457): "A thin leaf is inserted in the pith of the cone which overlays the centre of, and extends half an inch beyond, the point of each scale"-an important character in the species now observed, but from what is stated of it generally it belongs to neither.21

David Douglas


17. Given the latitude and longitude (corrected to 115(W), this would be at the eastern base of the Rocky Mountains at Rocky Mountain House, Alberta, Canada, where Douglas arrived on 3 May 1827 on his trip from the Columbia River to Hudson's Bay. He was now seeing the Rocky Mountain Douglas-fir (Pseudotsuga menziesii var. glauca (Beiss.) Franco) but did not distinguish between this and the coast variant. The needles of the coastal var. menziesii are yellowish-green on pubescent twigs whereas those of var. glauca are bluish-green to dark green or gray-green on glabrous or pubescent twigs. The most distinctive difference is in the cones. The three-pointed cone bracts of var. menziesii are appressed to the body of a 6-10 cm long mature cone. The bracts of var. glauca are spreading or even reflexed away from the body of a 4-7 cm long mature cone. In addition, the coastal phase is a much taller tree, reaching a height of 90 m or more, while the Rocky Mountain phase rarely is 50 m in height. The overall range of the var. menziesii is from southwestern British Columbia to central California eastward basically into the Cascade and Sierra Nevada ranges. The var. glauca occurs in the Rocky Mountains of central British Columbia and southwestern Alberta southward into Mexico. It also is found in the Cascade Range at higher elevations than var. menziesii such as on the slopes of the volcanic peaks of Mt. Hood, Mt. St. Helens and Mt. Baker, and is the common expression on the Blue Mountains. Like Lewis and Clark before him, Douglas did not distinguish between the two varieties, a distinction that would not be made until both expressions were grown together in European gardens where detailed observations could be made.

18. Today, Douglas-fir is one of the most economically significant forest trees for lumber in the world. It is widely planted as a commercial forest tree in Europe and in scattered regions of Asia and in Australia. Young, immature trees are often favored as Christmas trees, and the Rocky Mountain Douglas-fir is frequently planted as an ornamental. The tree is particularly common in the British Isles where it is often used as a windscreen along the edges of fields, highways and especially airport runways.

19. Douglas refers to the 1814 Biddle edition of Lewis and Clark's History of the expedition under the command of Captains Lewis and Clark published in Philadelphia. Douglas may well have purchased a copy while in Philadelphia in 1823. The following quote was written by Lewis on ? Feb 1806.

20. Although individual trees of coastal Douglas-fir rarely exceed 90 m (ca 295 feet), there are historical reports of trees reaching 100 m (ca. 328 feet). The Flora of North America, for example, indicates the tree rarely reaches 100 m, but Hitchcock et al. (1969) indicate the tree does not exceed 90 m.

21. Lewis' tree "No 5." was indeed Douglas-fir. The three-point bract on the cone is unique to the genus Pseudotsuga. See Moulton (1990) and Lewis' entry for 6 Feb 1806.