Jack pine is a common tree on dry spots in the boreal forest, but not so common to find in Montréal. It has a tough appearance, with two short, twisted needles per bunch. It bears regular cones that open when the seeds inside are ripe (numbered 7 in the illustration) and serotinous cones (numbered 6 in the illustration) which remain closed until such a time as the resin on the outside has been melted, making this species specially adapted to establishing new stands after forest fires.