Subalpine Fir

Subalpine fir (Abies lasiocarpa) is a high-elevation conifer of the subalpine zone in Banff National Park. It grows with Engelmann spruce and forms the upper limit of forest at treeline.

Identification: Tall, narrow, spire-like crown; smooth gray bark with resin blisters; flat needles (soft, not sharp) with two white stripes beneath; upright cones (purple when young) that disintegrate on the tree. Distinguish from spruce: fir needles are flat and soft; spruce needles are four-sided and sharp.

Habitat: Lower to upper subalpine (1,650–2,200 m); often dominant with Engelmann spruce. Prefers moist, cool sites. At treeline, forms krummholz (stunted, wind-shaped); distinctive “flag” form on exposed ridges.

Ecology: Important winter browse for elk and deer; seeds and foliage eaten by birds and small mammals. Subalpine fir–Engelmann spruce forest covers ~53% of Banff’s subalpine zone.