Northern Pin Oak

About Northern Pin Oak in Alberta

Northern pin oak, Quercus ellipsoidalis, is a distinct red-oak-group species from regular pin oak, Quercus palustris. It is native in Canada only to Ontario according to VASCAN, not Alberta. Alberta sources nevertheless recognize it as a separate planted landscape tree: the Alberta Tree Species Rating Guide gives it ratings for Calgary, Red Deer, and Edmonton, and Edmonton's landscape standards list it separately from regular pin oak. For ARA, treat it as an introduced planted tree where documented, not a native Alberta oak. The most important identification warning is that deeply lobed, bristle-tipped leaves occur in several red oaks; mature ellipsoid acorns with relatively deep cups, whole-tree form, and planting evidence are needed to separate northern pin oak confidently from regular pin oak.

Identification: Leaves are alternate and simple, usually about 7-12 cm long, though North American references also give 3-6 inches. They commonly have about seven bristle-tipped lobes separated by deep, rounded U-shaped sinuses that can approach the midrib. This creates a finely cut or lacy outline. Leaves emerge red-tinged and can be hairy in early spring, become green in summer, and often turn bright scarlet, red, or deep purple in fall. Lower surfaces are generally hairless but may have small tufts in vein axils. Deep lobing alone is not a safe identification because regular pin oak, black oak, scarlet oak, and other red-oak-group trees may overlap.

Alberta range and habitat: No native, wild, or naturalized Alberta distribution was verified. VASCAN records the Canadian provincial distribution in Ontario. Treat Alberta northern pin oaks as planted unless future evidence establishes another status.