Spruce - willow - birch zone

In the spruce-willow-birch zone (SWB zone), conditions are harsh, with bitterly cold, snowy winters and short cool summers. However, the pristine environment, wonderful scenery, and abundant wildlife make the zone ideal for a variety of recreational activities.

Although the steep, mountainous terrain is unsuited to human habitation, resident wildlife are well adapted to its winter conditions. Forest cover is sparse and made up mostly of coniferous species, except on warmer slopes, where trembling aspen often dominates. Other dominant vegetation in the zone includes deciduous shrubs, especially scrub birch and several species of willows and grasses, primarily Altai fescue.

The SWB zone occupies subalpine elevations in the northern third of the British Columbia interior. It extends north well into the Yukon and the Mackenzie District of the Northwest Territories.

This is a mountainous area that includes the northern Rocky Mountains, the Cassiar and northernmost Omineca and Skeena mountains, part of the St. Elias Mountains, and much of the Stikine, Yukon, and Liard plateaus. There are no significant settlements in this zone, but several active mining camps are located here.