Pseudots_info.html

Pseudotsuga menziesii (Douglas-fir): Information.
Identifying characteristics: The common name is misleading as this tree is not a fir at all-although it was once named Picea douglasii and P. taxifolia. When young, the Douglas-fir has a compact, pyramidal crown, becoming cylindrical, more open, and flat-topped with age. It is usually 40 to 80 feet tall, but can grow to 300 feet, and can live to 1000 years. The evergreen leaves are linear, flattened and 1 to 1.25 inches long, with short leaf stalks. They are bluish-green above, with 2 white lines below and are spirally arranged, extending in all directions from the twig. Leaves smell like camphor when bruised. The midvein is prominent and the leaf tips are blunt or rounded. Cones are 2 to 4 inches long, pendulous and oval. They are initially purplish, turning yellowish-brown and falling intact. The scales are nearly circular, interspersed with 3-pronged bracts that protrude beyond the cone scales. Cones mature in one season and persist into winter. Buds are ovoid-elongate, large (0.2 to 0.3 inches long) and pointed, with reddish-brown, overlapping scales. Bark on young trees is gray and scaly, with numerous resin pockets. On older trees bark becomes deeply furrowed with oblong, reddish-brown scales. Similar species: Ecology: Distribution: The Douglas-fir is native to the Rocky Mountains and the Pacific Coast (from British Columbia to Mexico). There are two varieties of this species. The variety native to the Rocky Mountains (P.menziesii var glauca) and has smaller cones (2 to 3 inches long) with reflexed bracts. The Pacific Coast variety requires atmospheric moisture, has larger cones, straight bracts and dark green foliage. The Rocky Mountain variety, more tolerant of cold and drought, is planted in the Midwest. Habitat: The Douglas-fir grows best on neutral or slightly acid, well-drained, moist, deep, loamy soils. It requires full sun, plenty of free air movement and good soil moisture. High winds and heavy, wet snows may be damaging, and poor, dry soils will adversely affect growth. Growth is initially slow, becoming moderate. This species is usually free of pests and diseases, but Swiss needlecast, Douglas-fir bark beetle and cankers can be problematic. Uses: Wood: This is one of the most important commercial timber trees in the world. It is the major source of timber for plywood and construction lumber sold in the the central and western states. The wood is soft, light, does not warp and takes a fine finish. It is used for pulp, vats, tanks, railroad ties, structural beams, docks, bridges and interior finish. In the west it is used for Christmas trees. Wildlife: Douglas-fir is important to wildlife. The small, winged seeds feed western squirrels, other rodents, and birds. Foliage and male cones are eaten by blue grouse in the winter. Mountain goats and sheep, elk and deer browse the foliage and twigs. It provides cover for wildlife in winter. Horticulture: This species is an attractive ornamental for use in northern climates. It is not a good choice for underplanting (requires sun) or windbreaks (wind breakage). It is sometimes planted in Iowa for wildlife plantings and landscaping, but it should not be planted in dry, exposed sites.

Pseudotsuga menziesii (Douglas-fir): Information.

Identifying characteristics:
The common name is misleading as this tree is not a fir at all-although it was once named Picea douglasii and P. taxifolia. When young, the Douglas-fir has a compact, pyramidal crown, becoming cylindrical, more open, and flat-topped with age. It is usually 40 to 80 feet tall, but can grow to 300 feet, and can live to 1000 years. The evergreen leaves are linear, flattened and 1 to 1.25 inches long, with short leaf stalks. They are bluish-green above, with 2 white lines below and are spirally arranged, extending in all directions from the twig. Leaves smell like camphor when bruised. The midvein is prominent and the leaf tips are blunt or rounded. Cones are 2 to 4 inches long, pendulous and oval. They are initially purplish, turning yellowish-brown and falling intact. The scales are nearly circular, interspersed with 3-pronged bracts that protrude beyond the cone scales. Cones mature in one season and persist into winter. Buds are ovoid-elongate, large (0.2 to 0.3 inches long) and pointed, with reddish-brown, overlapping scales. Bark on young trees is gray and scaly, with numerous resin pockets. On older trees bark becomes deeply furrowed with oblong, reddish-brown scales.

Similar species:

Ecology:
Distribution: The Douglas-fir is native to the Rocky Mountains and the Pacific Coast (from British Columbia to Mexico). There are two varieties of this species. The variety native to the Rocky Mountains (P.menziesii var glauca) and has smaller cones (2 to 3 inches long) with reflexed bracts. The Pacific Coast variety requires atmospheric moisture, has larger cones, straight bracts and dark green foliage. The Rocky Mountain variety, more tolerant of cold and drought, is planted in the Midwest.

Habitat: The Douglas-fir grows best on neutral or slightly acid, well-drained, moist, deep, loamy soils. It requires full sun, plenty of free air movement and good soil moisture. High winds and heavy, wet snows may be damaging, and poor, dry soils will adversely affect growth. Growth is initially slow, becoming moderate. This species is usually free of pests and diseases, but Swiss needlecast, Douglas-fir bark beetle and cankers can be problematic.

Uses:
Wood: This is one of the most important commercial timber trees in the world. It is the major source of timber for plywood and construction lumber sold in the the central and western states. The wood is soft, light, does not warp and takes a fine finish. It is used for pulp, vats, tanks, railroad ties, structural beams, docks, bridges and interior finish. In the west it is used for Christmas trees.

Wildlife: Douglas-fir is important to wildlife. The small, winged seeds feed western squirrels, other rodents, and birds. Foliage and male cones are eaten by blue grouse in the winter. Mountain goats and sheep, elk and deer browse the foliage and twigs. It provides cover for wildlife in winter.

Horticulture: This species is an attractive ornamental for use in northern climates. It is not a good choice for underplanting (requires sun) or windbreaks (wind breakage). It is sometimes planted in Iowa for wildlife plantings and landscaping, but it should not be planted in dry, exposed sites.