Douglas fir Douglas-fir forest is the primary habitat of the red tree vole ("Arborimus longicaudus") and the spotted owl ("Strix occidentalis"). Home range requirements for breeding pairs of spotted owls are at least 400 ha () of old growth. Red tree voles may also be found in immature forests if Douglas-fir is a significant component. The red vole nests almost exclusively in the foliage of the trees, typically above the ground, and its diet consists chiefly of Douglas-fir needles. A parasitic plant sometimes utilizing "P. menziesii" is Douglas-fir dwarf mistletoe ("Arceuthobium douglasii"). The leaves are also used by the woolly conifer aphid
Robert Douglas, Count of Skenninge and died without issue. The daughter married an Oxenstierna. The remaining son, Gustaf, was first of the Swedish-born noble line of Douglas. He became a Colonel and Governor of Västerbotten. The Swedish noble family of Douglas descends from him. His grandson, Count Gustav Otto Douglas, was captured by the Russians during the Battle of Poltava, entered Russian service, and in 1717 was made Peter the Great’s Governor General over Finland. In the 1890s the then head of the family, Count Ludvig Douglas, was the Swedish foreign minister and Marshal of the Realm. His father Count Carl Israel Douglas (1824-1898) had