Trees are a vital part of the world around us. Not only do they provide important ecological functions, but they also serve as markers of our cultural heritage. The Heritage Tree Program, run by Forests Ontario along with key program supporter TD, recognizes unique and historically significant trees found all across the province. The hope of the program is to illustrate the valuable role trees have played in shaping our communities in the past, present, and into the future.
The Cucumber Magnolia (HT 2017-202-214) was recognized as a heritage tree in October 2017. Commonly referred to as a Cucumber tree, this tree is a native of the Appalachian Belt, although there are isolated populations found in the southeastern United States and southern Ontario. It’s remarkable that such a large and robust specimen is growing as far north as Owen Sound, Ontario, well outside of its Carolinian Zone. The Carolinian Zone is characteristically much warmer throughout the seasons than other parts of Ontario, allowing the region to support tree species that typically grow further south (Government of Canada, 2014). Additionally, almost 50% of the tree species that are listed as at risk in Canada are found in this particular zone (Government of Canada, 2014). This list includes the Cucumber tree, which is considered an endangered species in Canada and, as such, is protected under the Canadian Species at Risk Act. It’s no wonder this tree is widely admired across the county.
This glorious tree dominates the front lawn of the John MacLean House, the historic home of a well-documented and prominent family in Owen Sound. Archival accounts of the home and family provide an interesting glimpse into early life in the city, often including references to trees. In an interview with the Owen Sound Sun Times, Elizabeth MacLean (the oldest resident at the time) recounted that “passenger pigeons roosted by the thousands in the trees, and young men went out each morning and shot them by the hundreds.” As passenger pigeons were eventually hunted into extinction, this tree serves as a reminder of not only human history, but also of the ecological history this tree has witnessed in the past and will continue to witness (Zimmer, 2014). An endangered species itself, this tree speaks to the significant impact humans can have on the environment. Due to sprawling urbanization, the growth of industry, and intensive agricultural production, it is estimated that 90% of the original Carolinian forests in Ontario have disappeared (Government of Canada, 2014). This loss makes the story of this Cucumber tree even more prevalent and underscores the importance of recognizing and preserving the historic trees that can be found all across Ontario.
The overall ecological impact of a tree that is almost 100 years old is quite remarkable in itself. Over the tree’s lifetime, it has intercepted approximately 2.7 million litres of rainwater – more than enough to fill an Olympic size pool (Davey Tree, 2018). The process of rainwater interception is very important in an urban setting, as it helps reduce the risk of flooding and improves water quality (Kermavnar and Vilhar, 1). Additionally, this Cucumber tree has diverted a total of 9,400 kilograms of carbon dioxide, which is enough carbon dioxide to power a house for a year (Davey Tree, 2018).
Acknowledging and sharing the ecological benefits of historic trees is a key component of the Heritage Tree Program. Trees that have been able to grow and thrive over the course of many human lifetimes not only serve as a reminder of the past, but of the incredible resiliency of the trees we see every day. If you are aware of a tree with an important history that you would like to celebrate through the Heritage Tree Program, we are always looking for nominations. For a full description of the nomination process, click here: www.forestsontario.ca/wp-content/uploads/2016/01/Nomination-Process-One-Pager.pdf
The Heritage Tree Program is run by Forests Ontario in partnership with key program supporter TD. The Program works to recognize unique and historically significant trees that can be found throughout Ontario. To learn more visit: https://www.forestsontario.ca/community/in-the-spotlight/heritage-trees/
Davey Tree. “National Tree Benefit Calculator” last modified 2018. Accessed July 5,2018 from <http://www.davey.com/arborist-advice/articles/national-tree-benefit-calculator/>.
Kermavnar, Janez and Urša Vilhar. “Canopy precipitation interception in urban forests in relation to stand structure.” Urban Ecosyst, no. 20 (2017):1373–1387. DOI 10.1007/s11252-017-0689-7.
Government of Canada. “Conserve Ontario’s Carolinian Forests: preserve songbird species at risk, chapter 1, Ontario’s Carolinian Zone” last modified September 15, 2014. Accessed July 18, 2018 from <https://www.canada.ca/en/environment-climate-change/services/migratory-bird-conservation/publications/ontario-carolinian-forests-preserve-songbird/chapter-1.html>.
Zimmer, Carl. “Century After Extinction, Passenger Pigeons Remain Iconic—And Scientists Hope to Bring Them Back” National Geographic. August 30, 2014. Accessed July 18, 2017 from <https://news.nationalgeographic.com/news/2014/08/140831-passenger-pigeon-martha-deextinction-dna-animals-species/>.