Jack pine

Silhouette - jack pine
  • Latin name: Pinus banksiana Lamb.
  • French name: Pin gris
  • Synonym(s): Scrub pine , gray pine , banksian pine
  • Taxonomic Serial Number: 183319
Description

Leaves

  • Needle cross section - jack pine
  • Needle bundle - jack pine

Form

  • Needles evergreen
  • In bundles of 2
  • Straight or slightly twisted, stiff
  • Sharp-pointed, spread apart
  • Edges toothed
  • Bundle-sheath persistent

Length

  • 2–4 cm

Colour

  • Light yellowish-green

Buds

  • Terminal and subterminal buds - jack pine

Form

  • Blunt-pointed, resinous

Length

  • To 15 mm

Colour

  • Pale reddish-brown

Twigs

Form

  • Slender, ridged and grooved
  • Vigorous shoots on young trees usually with 1 or more intermediate nodes bearing loose whorls of side branches

Colour

  • Yellowish-green becoming dark greyish-brown in second season

Seed cones (mature)

  • Cone scale outer surface (left), seed and cone scale inner surface with winged seed (center), cone scale profile (right). - jack pine

Form

  • Variable in shape
  • Oblong to conical, asymmetrical
  • Straight or curved inward
  • Stalkless, usually pointing forward
  • Often in clusters of 2 or 3 at nodes
  • Usually remaining closed and persistent on the tree for 10–20 years

Length

  • 3–7 cm

Colour

  • Yellowish-brown when mature

Structure

  • 80 scales, thickened at the tips
  • Smooth (sometimes with a minute prickle)
  • Held closed by a resin bond

Timing

  • Open when exposed to heat from a wildfire or sometimes from direct sunlight on warm days

Seeds

Form

  • Often ridged

Length

  • Seed 3 mm
  • Seed wing about 10 mm

Colour

  • Dark brown or black

Seedlings

Form

  • 3–6 cotyledons, toothless

Lenght

  • 12–24 mm

Bark

Form

  • Thin when young, becoming flaky
  • With age furrowed into irregular thick plates

Colour

  • Reddish-brown to grey when young, becoming dark brown

Wood

Texture

  • Moderately hard and heavy, weak

Colour

  • Light brown

Uses

  • General construction, wood pulp, railway ties, poles, pilings, and mine timbers

Size

Height

  • To 20 m, occasionally larger

Diameter

  • To 30 cm

Maximum age

  • 150 years

Tree form

  • Silhouette - jack pine

Open-grown

Trunk

  • Tapered

Crown

  • Conical, open
  • Branches ascending, arching

Forest-grown

Trunk

  • Slender, straight, with little taper

Crown

  • Short

Root system

  • Wide-spreading, moderately deep
  • Often with a taproot

Habitat

Site

  • Coarse sands, shallow soils, and rock out-crops, permafrost
  • On poor soils and rocky sites, tree short, often twisted, with long stout branches, some dead or dying, giving the crown an unkempt appearance
  • After extensive fires, jack pine may occupy all sites from ridge tops to muskegs

Light tolerance

  • Intolerant of shade

Associated species

  • Grows in pure stands or mixed with other shade-intolerant species such as white birch, trembling aspen, balsam poplar, red pine, and tamarack
  • Shade-tolerant species such as black spruce, white spruce, and balsam fir often form the understory

Range

Most widely distributed pine in Canada

Insects and diseases

Insects and diseases that are found most frequently and/or that cause the most damage in our Canadian forests.

Photos
  • Jack pine
  • Jack pine
  • Jack pine
  • Jack pine
  • Jack pine
  • Jack pine
  • Jack pine
  • Jack pine
  • Jack pine
Distribution map
Distribution map - jack pine
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