Betula neoalaskana Betula neoalaskana Betula neoalaskana (syn. "B. resinifera") or Alaska birch, also known as Alaska paper birch or resin birch, is a species of birch native to Alaska and northern Canada. Its range covers most of interior Alaska, and extends from the southern Brooks Range to the Chugach Range in Alaska, including the Turnagain Arm and northern half of the Kenai Peninsula, eastward from Norton Sound through the Yukon, Northwest Territories, British Columbia, Alberta, Saskatchewan, Manitoba, southern Nunavut, and into northwestern Ontario. This tree typically grows to tall, occasionally up to , and achieves a trunk diameter of , and sometimes
Pterocarya fraxinifolia appear in April, the male catkins thick and green, 7.5 – 12.5 cm long, the females longer with less dense flowers, bearing red styles forming fruiting catkins 30 – 50 cm long, the green, winged, nuts approximately 1.8 cm wide. The species is fast growing and grows best on flat ground or shallow slopes near river banks and in deep moist soils. The climate associated with the distribution of this tree includes mild winters and mild humid summers. It generally grows in mixed stands with other species and rarely grows in pure stands. Fossils of "Pterocarya fraxinifolia" have been described