DOUGLAS FIR (CLEARS)
THE TREE
DOUGLAS FIR, ALSO KNOWN AS COLUMBIAN AND OREGON PINE THOUGH BOTANICALLY NOT A PINE, IS ONE OF THE WORLD’S OUTSTANDING SOFTWOODS. IT IS OBTAINED IN BRITISH COLUMBIA AND ON THE PACIFIC COAST OF THE UNITED STATES FROM A MAGNIFICENT TREE, COMMONLY 50 TO 60m HIGH AND EXCEPTIONALLY UP TO 90m, WITH A LONG STRAIGHT BOLE 1 TO 2m AND SOMETIMES MORE IN DIAMETER. IT IS GROWN AS A PLANTATION TREE IN TEMPERATE COUNTRIES, INCLUDING BRITAIN.
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THE WOOD
DOUGLAS FIR IS A PALE TO MEDIUM RED-BROWN, WITH A CONSPICUOUS GROWTH-RING FIGURE, PARTICULARLY ON FLAT-SAWN OR ROTARY-CUT SURFACES. TYPICALLY IT IS STRAIGHT GRAINED, OFTEN SOMEWHAT RESINOUS AND OF MEDIUM WEIGHT FOR A SOFTWOOD, MARGINALLY HEAVIER THAN EUROPEAN REDWOOD.
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TECHNICAL PROPERTIES
DOUGLAS FIR DRIES QUICKLY AND WELL, IS NOTED FOR ITS STRENGTH, AND WORKS READILY WITH HAND AND MACHINE TOOLS. IT IS MODERATELY RESISTANT TO DECAY.
USES
IT IS THE LEADING STRUCTURAL WOOD OF WESTERN NORTH AMERICA. IT IS AVAILABLE IN VERY LARGE SIZE, THOUGH THESE ARE BECOMING MORE DIFFICULT TO OBTAIN, AND IS USED AS BAULKS IN PILING AND FOR PIER, DOCK AND HARBOR WORK. IT IS USED IN BUILDING FOR ROOF TRUSSES AND LAMINATED BEAMS, AND IN JOINERY. IT IS AN IMPORTANT WOOD FOR RAILWAYS SLEEPERS AND FOR CHEMICAL VATS AND TANKS; IT IS USED FOR FLOORING AND DECKING, BUT SHOULD BE QUARTER-SAWN TO MINIMIZE SPLINTERING. IT IS THE WORLD’S MOST IMPORTANT SOURCE OF PLYWOOD, USED MAINLY FOR STRUCTURAL PURPOSES.
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SOFT WOODS:
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