1. Pinus banksiana Lamb. (jack pine) Pl.
21j,k,l; Map 73
Trees to 10(–25) m tall. Trunks with reddish brown to dark gray
bark, the surface breaking into scaly plates. Twigs orangish brown to reddish
brown, glabrous, often glaucous, turning gray to reddish brown with age. Leaves
in fascicles of 2, 2–4 cm long, with 2 vascular bundles, relatively stiff,
persisting 2–3 years. Fascicle sheaths usually persistent. Cones 3–5 cm long,
tan to light brown or yellowish brown, narrowly ovoid, asymmetrical, curved or
arched to the side (most easily seen before dehiscence), the scales not shiny,
mostly lacking spines, sometimes with a minute, curved spine near the tip. 2n=24.
Pollen shed March–May.
Introduced, reproducing locally in and around plantings
scattered throughout the state (native to the northeastern U.S. south to Illinois and Pennsylvania, Canada; widely introduced to the south of its native
range). Widely planted for wildlife habitat, less commonly as an ornamental.
This species has a scrubby, irregular growth form, and it is
not usually planted as a windbreak or in plantations but rather as an
ornamental or for erosion control. In its native habitat, the cones often
remain closed at maturity for several years until fire stimulates the release
of the seeds.