The Douglas Fir (Pseudotsuga douglasii).
Although the name of this tree in English and Latin might reasonably lead one to suppose that David Douglas, the intrepid botanical explorer, was the discoverer of it, that is not really so.
It was Archibald Menzies who first made it known to science, by means of herbarium specimens collected in 1792, when, as the companion of Vancouver, he visited the western coasts of North America. But Douglas, in his capacity of collector to the Royal Horticultural Society, landed at Fort Vancouver on the Columbia River in 1825, and not only sent home herbarium specimens, but seeds also, of this and several previously unknown Conifers. It was by means of these seeds that the Douglas Fir was introduced to Britain. It was already known by Lambert's name of Abies taxifolia, but Dr. Lindley, a short time previous to Douglas' untimely death, selected the tree as a suitable and enduring memorial of the enormous services Douglas had rendered, and named it Abies douglasii. Since then Carrière has split up the old genus Abies and placed douglasii in the new genus Pseudotsuga.
Under the most favourable natural conditions, as around Puget Sound and on the western slopes of the Sierra Nevada, the Douglas Fir grows to a height of 300 feet, with a girth of 30 to 40 feet, but on the drier slopes of the Rocky Mountains it is not more than 100 feet high. In Colorado, forests of Douglas Fir are found at an elevation of 11,000 feet. The tree has not been sufficiently long established in this country to say what dimensions it will reach, though it appears to have taken kindly to Ireland and to Devon and Cornwall, where the rate of growth of young trees is about 30 inches per annum. There are plenty of trees in these islands, planted about the year 1834, which have reached or passed 100 feet, and there is no doubt that towards our western coasts this height will be greatly exceeded. Some of these trees have long since produced cones, and from their seeds many young trees have been raised.
