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Natural
History Douglas-Fir (Pseudotsuga menziesii) Richard Hebda INDEX for Native Plants This text was originally published in Coastal Grower (formerly The Island Grower) in Victoria, British Columbia. For subscription information, please call Susanne Steele at the Coastal Grower at 250-478-0825. British Columbia is famous for its coniferous forests and the most famous of our species is the Douglas-fir. Named after David Douglas a Scottish botanical explorer of the late 1700s, this giant has been known to reach an age of well over 1000 years. Most of the original coastal forests are gone now but drought adapted youngsters thrive on the landscape, perhaps in anticipation of changing climates to come. Towering Douglas-firs may reach 70 - 90 m tall with spreading needle-covered branches. The grey bark develops large deep grooves as it thickens to fend off ground fires. The 2 - 4 cm long needles are slightly pointed and feel soft to the touch, not like spruce (Picea) species. Most true firs (Abies spp.) have notched needle tips. The interior subspecies of Douglas-fir has bluish green needles whereas the needles of the coastal subspecies are yellowish green. Soft reddish brown male cones produce a dusting of yellow pollen. The oval 5 - 10 cm (2-4") long female seed cones are most fascinating for they harken back to the Permian, 250 million years ago, when the first conifers evolved. Botanists believe that a female conifer cone originated by the reduction of large fertile branches. The cone axis is the main branch. The scales which produce the seeds are shortened and modified cone-bearing branches. The little bracts, which look like the back legs and tail of a mouse disappearing under the scale, are a modified leaf which once flourished at the base of the fertile branch. Together the two subspecies of Douglas-fir (interior and coastal) range throughout most of the southern third of B.C. The tree favours drier sites at medium to low elevations though both on the coast and in the interior it can reach timber line. The North American range extends from BC and Alberta south through the mountains to Mexico. Instead of planting exotic conifers such as cypresses from Asia, try Douglas-fir for it is easily grown from seed sown on moist sandy or humusy soil. Young seedlings growing where they are not wanted transplant easily. Special varieties like dwarf mutations are propagated by grafting. On the coast young plants are widely available from nurseries and garden centres. This adaptable tree can serve as a single specimen or be used to develop a rich green hedge for it responds well to trimming. Perhaps its most important value is to reforest cleared landscapes and abandoned fields. The certainly attracts wildlife and helps restore the original forest cover. Douglas-fir adapts well to urban settings provided you have the space. Douglas-fir served First Peoples in many ways. It supplied an excellent fuel. The wood was fashioned into many kinds of tools such as spear handles, fish hooks and fire tongs. The tree was also a most remarkable source of wild sugar. Rarely, a mass of sweet granular white resin formed on needles and cones and could be collected and chewed, apparently tasting like a mixture of sugar and honey. A tea made from twigs and needles made a tonic and peeled young branches were used as a mouth freshener. The pungent pitch was used as a salve for wounds. The botanical name means false (pseudo) hemlock (tsuga), with the species name honouring another early botanical explorer Archibald Menzies. Perpetuate our native forests and plant Douglas-firs for the future. For more information, contact Richard Hebda at the Royal British Columbia Museum.
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