Black spruce

Leaves

Form

• Straight, blunt-pointed
• Needles densely set along the twig
• Side needles at right angles, upper needles pointing forward

Length

• 8–15 mm

Colour

• Dull greyish-green
• Lines of white dots more prominent on lower surface

Buds

Form

• Conical, blunt-tipped; outer scales hairy with long slender points projecting beyond the tip of the bud, inner scales broader

Length

• 3–5 mm

Colour

• Outer scales dull brownish-grey
• Inner scales darker brown

Twigs

Form

• Leaf-cushions flat, grooves closed, with many short brownish hairs, which may be crooked and/or tipped with a gland
• Twigs of very young trees often hairless

Colour

• Dark orange-brown or yellowish-brown, dull, with a dark purplish stain at the base of the leaf-peg

Seed cones (immature)

Form

• Broadly ovoid
  
• Blunt-pointed, gradually tapered to a curved, short, scale-covered stalk

Length

• 2–3 cm

Colour

• Deep red to purple changing to dark purplish-brown

Structure

• Scales brittle, tight-fitting
• Margin irregularly toothed

Seed cones (mature)

Form

• Open cones almost spherical

Structure

• Scale margin thin, brittle, toothed

Timing

• Some cones produced nearly every year
• Mature in September
• Remain on the tree up to 30 years
• Often massed at the top of the tree

Seeds

Length

• Seed about 2 mm
• Seed wing 2–4 mm

Colour

• Dark

Bark

Form

• Thin, scaly or shredded when young
• Scales becoming larger

Colour

• Reddish- or greyish-brown when young, becoming darker
• Newly exposed bark olive-green or yellowish-green

Wood

Uses

• Wood pulp, lumber

Size

Height

• To 20 m on poorly drained sites
• To 30 m on well-drained upland sites

Diameter

• To 30 cm on poorly drained sites
• To 60 cm on well-drained sites

Maximum age

• 200 years

Tree form

Forest-grown

Crown

• On poorly drained sites, crown narrow, spire-like
• On well-drained upland sites, principal branches short compared with other spruces, lower ones greatly drooping, tips upturned
• Upper part of the crown often very dense, oddly shaped, with many cones

Root system

• Very shallow, especially on organic soils with a high water table

Habitat

Site

• Adaptable
• In the southern part of its range generally confined to wet poorly drained sites
• Usually a slow-growing wetland tree, but occurs frequently on upland sites
• Northward, usually grows on moist organic soils

Light tolerance

• Moderately shade-tolerant

Associated species

• In the southern part of its range, in pure stands or with tamarack
• Northward, in extensive pure stands, or mixed with jack pine, white spruce, balsam fir, white birch, trembling aspen, and lodgepole pine

Range

Transcontinental, southward into the United States