Douglas Fir
Its reddish-brown heartwood is distinctive from its cream white sapwood. Douglas fir is straight grained, with medium texture and sound knots.
Douglas firs are medium-size to extremely large evergreen trees, 20–100 meters (70–330 ft) tall (although only coast Douglas firs reach such great height).[4] The leaves are flat, soft, linear, 2–4 centimeters (0.8–1.6 in) long, generally resembling those of the firs, occurring singly rather than in fascicles; they completely encircle the branches, which can be useful in recognizing the species. The female cones are pendulous, with persistent scales (unlike true firs), and are distinctive in having a long tridentine (three-pointed) bract that protrudes prominently above each scale (it resembles the back half of a mouse, with two feet and a tail).
Its reddish-brown heartwood is distinctive from its cream white sapwood. Douglas fir is straight grained, with medium texture and sound knots.
Douglas Fir is naturally durable: Heartwood is resistant to mushrooms. Douglas-Fir can be used in Class 3 (timber exposed to weathering). Impregnation must be done by Vacuum pressure treatment.
