Good question. Short answer: they’re really old.
Bur oaks are one of the slowest growing and longest-lived native oaks in North America. They can live hundreds of years. The largest of the oaks in our neighbourhood are more than a metre in diameter, which means they are between 130 and 180 years old.
One tree (preserved at the Champlain Park Field house) has been dated by a specialist as having turned from acorn to sapling in 1856. That would make it 161 years old, had it not been felled as part of an infill development in 2010. Ottawa’s Urban Tree Conservation By-law, passed in 2009, did not conserve this giant bur oak. Visit the outdoor display at Champlain Park and the indoor interpretive panels at the fieldhouse to learn more about these heritage trees.