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The Douglas fir disk of the Nanquette pavilion
February 17 2025A remarkable example of Pseudotsuga menziesii, which celebrated its 700th birthday in 2009!
The tree from which I was extracted was born somewhere in western Canada a few years before 1309, the date that marks my central part, the first growth ring formed at the level of my removal, comprising the marrow and its primary formations surrounded by the first secondary elements from the libero-ligneous base, which was established at this level during the year 1309. When the tree was cut down in 1876, I therefore had 568 growth rings, or annual growths on the radius. (Obviously, this number has not changed since that date!). I was transported to Europe, probably to be displayed at the Universal Exhibition in Paris in 1878, then stored at what was then the National School of Water and Forestry, in the Mahy pavilion, now destroyed, which was on the site of the current student residence. In everyday language, the forest species from which I come is generally called “Douglas fir”, but it is sometimes called “Douglas fir”, when this species has grown in Europe, or even “Oregon fir”, when it is imported from the natural stands of North America. And yet, I come neither from a fir tree, nor a pine tree, nor even a hemlock, as the name of the genus to which I belong specifies: Pseudotsuga, meaning “false hemlock” or “resembling hemlock”, tsuga being a name of Japanese origin, as everyone knows.
To simplify things a little more, my common name “douglas” commemorates David Douglas (1799 - 1834), one of the botanists who described me, hence my former scientific name Pseudotsuga douglasii Carrière (1867), but my valid scientific name is Pseudotsuga menziesii (Mirb.) Franco (1950), which, according to the rule of anteriority, definitively dedicates me to Archibald Menzies (1754 - 1842) who discovered the species to which I belong on Vancouver Island in 1791.
An exotic species introduced to Europe in the 19th century, I have been very successful there due to my growth performance and the quality of my wood. I am currently the second most important softwood species in France, after maritime pine, with a production potential that will soon reach four million million cubic meters, from around 300,000 hectares, most of which were planted after 1945.
Seven hundredth anniversary: What does this mean for this sample?
To clarify the meaning of this figure, it is useful to refer to boxes 1 and 2 opposite. We do not (or no longer) have the information that would enable us to locate where this tree grew, to know the height h at which this disc was taken from the tree in relation to the ground, or to determine the exact age of the tree at the time it was felled. This age is equal to the number of growth rings counted on the tree slice, minus 1, plus the number n of years required for the young stem to reach the height hn after germination.
Françoise Huber and René Keller (avril 2009)
AgroParisTech - ENGREF - Campus de Nancy