Jack pine (Pinus banksiana)

Jack pine needles photograph; ? MN DNR, Rick Klevorn

Form

Straight trunk; height 25' to 60'; diameter 8" to 20"; top or crown of spreading branches and scant or open foliage. Small dead branches often remain on trees for many years.

Bark

Dull red-brown; irregularly divided into small scales.

Leaf

Needlelike, 3/4" to 1-1/2" long, stubby, flat, grayish green; two in a bundle and slightly twisted; remain on branchlets for about three years.

Fruit (seed)

Cones are about 1-1/2" long, often strongly curved, brown when ripe, turning gray later, sometimes remaining on branches unopened and containing good seeds for many years; small winged, triangular seeds can be carried far in strong winds. Many trees have ripe cones when seven years old.

Range

Found in abundance in north-central and northeastern Minnesota; occurs generally in pure stands on poor, sandy soil; usually the first of the pines to spring up and occupy land following fire; hardy and thrives on soil too poor for white or red pine; very shade intolerant.