Environmentalists will be thrilled that the Roundhouse's frame will consist not of old-growth Douglas fir but of recycled steel.

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According to the Guinness Book of World Records, the tallest Christmas tree ever cut was a 221-foot Douglas fir displayed in Seattle, Washington.

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Standing 38ft-high and constructed entirely of old-growth Douglas fir, the acoustically perfect dome rises out of the dusty Mojave Desert like a UFO, embodying the extra-terrestrial elements that inspired its construction.

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They did it on skis ridiculously long--14 to 16 feet--made of Douglas fir and bound to their feet with leather straps.

FORBES: Magazine Article