Douglas-fir (Pseudotsuga menziesii): what the agencies record

This page reports what US federal publications say about one tree. It does not identify trees from descriptions or photos and does not say what should be done with any tree. The family overview, tree species in the agency records, explains the sources and holds the comparison table.

At a glance

Item	What the source records
Scientific name	Pseudotsuga menziesii (Mirb.) Franco, pine family
Other names	Red-fir, Oregon-pine, Douglas-spruce and pino Oregon (Silvics); the Wood Handbook adds yellow-fir
Varieties, Silvics	Coast Douglas-fir (var. menziesii) and Rocky Mountain or blue Douglas-fir (var. glauca)
Native status, USDA PLANTS	Native in Canada and in the lower 48 states
Size in old-growth, Silvics	Trees 150 to 180 cm (60 to 72 in) in diameter and 76 m (250 ft) tall are common
Green weight of the wood, NRS-38	38 lb per cubic foot, without bark

Native range

The Silvics of North America handbook (Agriculture Handbook 654, volume 1, 1990) calls Douglas-fir one of the world's most important and valuable timber trees and says its fossil record shows a native range that has never extended beyond western North America. It describes the range as an inverted V with its apex in central British Columbia. The shorter arm runs south along the Pacific Coast Ranges for 2200 km (1,367 mi) and is the range of the coast variety. The longer arm runs along the Rocky Mountains into central Mexico over nearly 4500 km (2,796 mi) and is the range of the Rocky Mountain variety. The handbook records nearly pure stands from Vancouver Island through western Washington, Oregon and the northern California ranges, a common place in the mixed conifer forest of the Sierra Nevada as far south as Yosemite, a fairly continuous range through northern Idaho, western Montana and northwestern Wyoming, and a discontinuous distribution south through Utah, Nevada, Colorado, New Mexico, Arizona, extreme western Texas and northern Mexico.

Size and age

Silvics says the tallest tree on record, near Little Rock, Washington, was 100.5 m (330 ft) tall and 182 cm (71.6 in) in diameter. It calls coast Douglas-fir very long lived: ages above 500 years are not uncommon and some have exceeded 1,000 years. The oldest with an authentic record, about 48 km (30 mi) east of Mount Vernon, Washington, was slightly more than 1,400 years old when cut. On a medium site at low elevation, height growth averages 61 cm (24 in) a year at age 30 and 9 cm (3.6 in) a year at age 120.

Cones, roots and Christmas trees

The handbook says Douglas-fir is monoecious and that trees commonly begin to produce cones at 12 to 15 years of age. On rooting, it says a taproot forms first and in deep soils grows to about 50 percent of its final depth in 3 to 5 years, while platelike root systems develop in shallow soils or soils with a high water table. It also records Douglas-fir grown as a Christmas tree on rotations of 4 to 7 years, sheared each year to a pyramid-shaped crown.

Wood

The Wood Handbook (FPL-GTR-282, 2021) says the range runs from the Rocky Mountains to the Pacific Coast and from Mexico to central British Columbia. Sapwood is narrow in old-growth trees but may be as much as 7 cm (3 in) wide in second-growth trees of commercial size. It says young, moderately to rapidly growing trees have reddish heartwood and are sold as red-fir, and the very narrow-ringed heartwood of old-growth trees may be yellowish brown and is known on the market as yellow-fir. It says the wood varies widely in weight and strength, and that it is used mostly for building and construction in the form of lumber, piles and plywood.

Wood Handbook figure, coast type	Green	At 12% moisture content
Specific gravity (Table 5-3b)	0.45	0.48
Modulus of rupture, lbf per square inch (Table 5-3b)	7,700	12,400
Side hardness, lbf (Table 5-3b)	500	710
Moisture content of green wood, percent (Table 4-1)	37 heartwood, 115 sapwood	Not applicable

The green weight of the wood is in the NRS-38 table, the same figure used in the log weight calculator.

Pests and diseases the handbook names

Silvics (1990) says Douglas-fir is host to hundreds of fungi, but relatively few cause serious problems.

Root rots. Shoestring root rot (Armillaria mellea) and laminated root rot (Phellinus weirii), which it says have caused significant damage in plantations, and Rhizina undulata.
Heart rots. Of more than 300 heart rot fungi, red ring rot (Phellinus pini) is called the most damaging and widespread. Others it names are Fomitopsis officinalis, Fomitopsis cajanderi and Phaeolus schweinitzii in the Pacific Northwest, and Echinodontium tinctorium and Fomitopsis pinicola in the Southwest.
Needles and stem. A needlecast caused by Rhabdocline pseudotsugae, and the dwarf mistletoe Arceuthobium douglasii, which it calls the most damaging stem disease and says occurs through most of the range.
Nursery fungi. Species of Pythium, Rhizoctonia, Phytophthora, Fusarium and Botrytis.
Cone and seed insects. The Douglas-fir seed chalcid, Douglas-fir cone moth, fir cone worm, Douglas-fir cone gall midge and cone scale midge.
Foliage and bark insects. The Douglas-fir tussock moth and the western spruce budworm, which it calls the most important insect enemies, and the Douglas-fir beetle, which it calls a destructive pest in old-growth stands.

The guide on reporting a pest in the United States gives the office that takes sightings of regulated pests, and pests and diseases by country sets out which ones agencies regulate. Who may apply pesticides is in pesticide licences by country.