The Douglas-fir is one of the largest of Canada's conifers. It grows from 60 to 100 metres high. Its bark can be up to 30 cm thick. And it can live for up to 1000 years.

The Douglas-fir has large seed cones that hang from twigs. These cones have three- pronged bracts that are longer than the cone scales, a characteristic feature of Douglas-fir that distinguishes it from other conifers.

The Douglas-fir is a species that relies on forest fires for its survival. In the absence of fires, it would be rapidly replaced by its associates, western hemlock, amabilis fir, western redcedar and grand fir. Old Douglas-fir trees are particularly resistant to fire damage, and the Douglas fir quickly regenerates after forest fires.

Douglas-fir is found on a variety of soils, but grows best on sandy loams. It does poorly during long dry, hot periods, and therefore prefers coastal regions, such as the Pacific coast. It occurs from central British Columbia to California. Limestone soils hinder its growth and diminish its lifespan.

Its wood is heavy and strong. It is a source of wood pulp and lumber, in addition to being used for structural purposes, and in shipbuilding. It is used in many countries for landscape and reforestation purposes, and is highly rated in France for reforestation and interior finishings. As well, it is popular as Christmas trees.