By far the best-known is the very widespread and abundant
North American species Pseudotsuga menziesii, a taxonomically
complex species divided into two major varieties (
treated as distinct species or subspecies by some botanists):
coast Douglas-fir or "green Douglas-fir", on the Pacific coast;
and Rocky Mountain Douglas-fir or "interior Douglas-fir",
in the interior west of the continent extending as far inland as Calgary, Alberta.
from: Wikipedia