Betula pumila

This record is for a broad treatment of Betula pumila that includes B. borealis as recognized by Furlow's treatment in FNA (1997, vol. 3). Furlow also includes B. pumila var. glabra, var. glandulifera, and var. renifolia (which were recognized as distinct varieties in Kartesz 1994, 1999)) in the synonymy of B. pumila. Brouillet et al. (in Vascan, accessed 2025) also include B. borealis, B. pumila var. glabra, and var. renifolia as indistinct from typical B. pumila, but they do recognize B. pumila var. glandulifera as a distinct variety.

Bog Birch (Betula pumila) occurs in North America, in the northern Continental United States, and across Boreal Canada. There are estimated to be more than 1000 occurrences, including in various National Forests, State Parks and State Forests in the United States, and National and Provincial Parks in Canada. It often occurs in large colonies. Some climate change related threats include increased insect herbivory, associated with higher temperatures and increase in summer fire impacts associated with higher temperatures and drought.

Bog Birch (Betula pumila) occurs in North America, in the northern Continental United States, and across Boreal Canada. It is known from St. Pierre and Miquelon, in Canada from Alberta, British Columbia, Manitoba, New Brunswick, Newfoundland, the Northwest Territories, Nova Scotia, Ontario, P.E.I., Quebec, Saskatchewan, and Yukon, in the United States from Colorado, Connecticut, Idaho, Illinois, Indiana, Iowa, Kansas, Maine, Massachusetts, Michigan, Minnesota, Montana, Nebraska, New Jersey, New York, North Dakota, Ohio, Oregon, Pennsylvania, South Dakota, Vermont, Washington, Wisconsin, and Wyoming. Range extent was estimated to be 10 million square kilometers, using herbarium specimens and photo-based observations documented between 1993 and 2024 (FNA 1997, GBIF 2024, iNaturalist 2024, NatureServe 2024, POWO 2024, SEINet 2024).

By applying a 1 km separation distance to herbarium records and photo-based observations documented between 1993 and 2024, there are estimated to be more than 1000 occurrences of Bog Birch (Betula pumila) rangewide (GBIF 2024, iNaturalist 2024, SEINet 2024).

Threats to Bog Birch (Betula pumila) may be similar to the climate change related threats to Tundra Dwarf Birch (Betula glandulosa), including increased insect herbivory, associated with higher temperatures (Barrio et al. 2017), and increase in summer fire impacts associated with higher temperatures and drought (de Groot and Wein 2004).