Betula glandulosa, American Dwarf Birch, also known as Resin Birch or Shrub Birch, is a species of birch native to North America, occurring in arctic and cool temperate areas from Alaska east to Newfoundland and southern Greenland, and south at high altitudes to northern California and Colorado in the west, and locally south to northern New York in the east. In the Arctic it occurs down to sea level, while in the south of the range, it grows as high as 3400 meter altitude. In Mid October 2007 a thicket of this plant was observed in flower in the foothills behind Palo Alto, California amidst Oaks, Bay Laurel and Manzanita. American Dwarf Birch is a multi-stemmed shrub typically growing to 1-3 meter tall, often forming dense thickets. The trunks are slender, rarely over 5-10 centimeter diameter, with smooth, dark brown bark. The leaves are nearly circular to oval, 0.5-3 centimeter long and 1.2.5 centimeter broad, with a toothed margin. The fruiting catkins are erect, 1-2.5 centimeter long and 5-12 millimeter broad.