Trees form an essential part of the landscape of any city, and Montreal is no exception. Their functions include the following:
● Providing shade;
● Purifying the air;
● Beautifying neighbourhoods and providing ornamental value;
● Improving curb appeal and adding to property values;
● Saving on home heating and air conditioning costs.
In fact, the Montreal Tree Policy, formulated by the city in 2005, recognizes the importance of trees to the cityscape and to the local citizens; it also recognizes the need to maintain trees and to ensure their continuing viability. The Policy does not, however, distinguish between native and exotic tree species.
Many streets in Montreal are lined with tree species not native to the Montreal region, such as Norway maple, honey locust, gingko, little-leaf linden, and Colorado spruce. Such introduced species are native to other parts of North America or to Europe or Asia. Exotic tree species, which are often invasive, tend to interfere with the local ecology and simplify the diversity of tree species in the area. Such exotic species have been planted with landscape architecture and/or horticulture more than ecology and sustainability in mind.
It is much better to plant tree species that are indigenous to the region, as opposed to introduced species. This is because native species, compared to non-native species:
● Are more accustomed to local climate and soil conditions;
● Attract more local wildlife;
● Require less maintenance;
● Can help restore the local ecology (if only partially) and add to tree diversity.
Tree species indigenous to the Montreal, Canada area include:
● Sugar maple (whose leaf is the symbol of Canada);
● Silver maple;
● White birch;
● Canadian hemlock;
● Common hackberry;
● Red ash;
● White oak;
● American linden;
● American elm.
Many American elms, formerly a favourite species for street trees, were eradicated by Dutch Elm Disease through the 1960s, but some remain. The more diverse the species planted, the more resistance to disease there will be; wildlife favour species diversity over monocultures.
Should municipal tree plans favour the planting of native vs. exotic tree species?
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