Culture
Grow in average, medium moisture, well-drained sandy loams in full sun. Very little tolerance for shade. Best growth is in geographic areas with cool summers and cold winters. Tolerates a wide variety of soils.
Noteworthy Characteristics
Pinus banksiana, commonly called Jack pine, is a scrubby northern pine that is native throughout much of Canada from the Northwest Territories to Nova Scotia south to the Great Lakes and northern New England. It grows further north in Canada than any other native pine. It is often found in the wild on poor, dry, sandy, barren plains. This is a small to medium sized conifer that typically grows to 35-50’ tall. It is a scraggly tree with a somewhat pyramidal shape that becomes open and irregular with age. Due in large part to shading from the sun, lower branching often dies but remains on the tree. Jack pine is particularly noted for its short, stiff, olive green needles (to 1.5” long) in bundles of two, its strongly-curved cones (to 2.5” long) and its ability to grow in poor soils. Needles may develop yellowish tones in winter. Cones ripen in two years, either opening at maturity or remaining closed on the tree for as much as 10 or more years. Closed cones are serotinous (sealed by resin), but will open after forest fires to distribute seed for new growth. Gray to reddish brown bark develops irregular fissuring with age. The sole breeding grounds for the rare Kirtland’s warbler are certain dense tracts of young jack pines (less than 20’ tall) in northern Michigan.
Genus name comes from the Latin name for pines.
Specific epithet honors Joseph Banks (1743-1820), an explorer, naturalist, botanist, plant collector and first director (commencing 1772) of Kew Gardens in England.
Problems
In cool summer climates, healthy, well-maintained trees usually have few major problems. These trees often struggle in the St. Louis area where hot summers, soils and general environmental conditions do not favor most pines. Needle cast, root rots and rusts may occur. In some areas, jack pine budworm is the most significant insect pest. Other insect pests include sawflies, tussock moth and pine needle miner.
Uses
Generally not recommended for specimen or ornamental growth in the St. Louis area due to its somewhat coarse and shabby appearance. Will grow in poor soils. Windbreaks.