Spruce-Pine-Fir (SPF)

A marketing group, not a species: several interchangeable northern softwoods graded and sold under one stamp.

Mengapa ini penting?

SPF is the volume commodity of the northern framing market and the reason Canadian lumber exports are politically contentious in the United States. Grouping species is what makes a commodity possible - a builder orders SPF and does not care which of the species arrives.

Where it grows

The boreal forest - Canada above all, plus the Nordic countries and Russia selling the same species under their own grade rules.

What it is used for

Wall and floor framing, trusses, furniture parts, pulp.

What to watch

Light, pale, stable and easy to work, but weaker than Douglas fir and poor at taking preservative. Slow boreal growth gives tight rings and better strength per unit density than fast-grown wood.