Gray Birch - Betula populifolia
The Gray Birch only grows to about 12m and can live about 50 years. This pioneer species loves open, dry soils, and loves to colonize open areas, including those created by human disturbances. The specific name populifolia means ‘with poplar-like leaves’. Grey Birch leaves are similarly shaped to poplar species, and will tremble in the smallest breeze. Small mammals and birds love the seeds and catkins of the Gray Birch, which form in the fall and mature the following spring.
Gray Birch trees often have distinct black patches underneath their branches, due to the fungus Pseudospropes longipilus. Photo by Chris Earley.
These unique birch leaves are triangular with a distinct slender tip. These triangular leaves measure 4-7 cm long and are shiny green on both sides. A unique aspect of the Gray Birch is that there are two distinct sizes of leaves and the larger ones sometimes appear to have lobes. Photo by Chris Earley.
The pollen catkins of the Gray Birch are usually found in isolation and measure around 2 cm in the winter and can grow up to 10 cm during pollination.
These buds are pointed and semi uniform exhibiting a light brown-grey colour and are usually hairy. Photo by Sean Fox.
Ontario Tree Atlas map of non-planted Gray Birch. 1995-1999.
References
Farrar, J.L.. 1995. Trees in Canada. Fitzhenry & Whiteside Ltd. Toronto. ON. 504 pp.
Kershaw, L. 2001. Trees in Ontario: Including tall shrubs. Lone Pine Publishing. Edmonton. AB. 240 pp
Muma, W. 2011. Ontario Trees and Shrubs. [Online] Available: www.ontariotrees.com
OMNR, 2011. Ontario Ministry of Natural Resources: Ontario Tree Atlas. [Online] Available: http://www.mnr.gov.on.ca/en/Business/ClimateChange/2ColumnSubPage/267027.html
OMNR, 2008. Ontario’s Biodiversity: Species at Risk.