This past October 29, in a light-hearted atmosphere, 131 young people from secondary 3 at Collège Charlemagne in Montréal lent a hand to counter the proliferation of buckthorn, an invasive exotic plant. In all, 20,300 buckthorn plants were removed from a wooded area over a surface of 1,260 m2.
That environmental-action day took place at the Cap-Saint-Jacques Nature Park and was piloted by the Biodôme and Ville de Montréal’s Service des grands parcs, du Mont-Royal et des sports.
What is buckthorn?
A native of Eurasia introduced to Québec in the early 20th century, buckthorn is a particularly invasive shrub in Montréal. The plants can cover 90 percent of a wood, creating a very dense ground cover harmful to the regeneration of native species. The majority of invasive plants, like buckthorn, were introduced for ornamental purposes. They managed to take root in new spaces in the absence of natural enemies. And they adapted and spread to different habitats, threatening biodiversity. On top of that, birds contribute greatly to the spread of their seeds.
Getting young people to participate in controlling invasive plant species is a way of connecting them with nature and sensitizing them to the biodiversity in urban wooded areas. The action is concrete and the result is visible immediately. The young people involved are agents of change and can also become multiplier agents by sharing their experience with those around them and raising their awareness in turn.
How do we recognize buckthorn?
- Early emergence of leaves in the spring and late defoliation in the fall.
- Brown or grey bark, yellowish wood.
- Height between 4 and 8 meters.
- Spine located at the tip of twigs over one year old.
- Leaves in opposite pairs, 3 to 5 veins curving upward towards the tip of the leaf.
- Clusters of dark fruit similar to blueberries, appearing in late summer and fall.
Why is it so invasive?
- Very rapid growth.
- Ability to take root in a wide variety of environments.
- Great fruit production.
- Seeds survive up to 3 years in the soil.
- Very high germination rate.
- Emergence of numerous shoots from cut stumps.
How do we take steps at home?
- Pull up young shoots and their roots.
- Cut mature plants as close as possible to the ground and cover the stump with opaque material (e.g., geotextile fabric, empty tin can) to prevent the formation of sprouts.
- Focus first on cutting shrubs with fruit.
- Maintain the intervention areas for several years: when spring comes, pull up the little seedlings and cut the stump sprouts.
- Place buckthorn residues in resistant and airtight trash bags and put them out for garbage pickup.
- Restore biodiversity by planting native trees and shrubs or at least noninvasive horticultural species.
How can I take part in citizen actions?
A number of non-profit organizations and citizen groups are involved in controlling buckthorn in Montréal and are normally looking for volunteers. You can contact them to join one of their environmental-action days; for example:
- Les amis de la montagne on Mount Royal
- Le Comité citoyen du parc Thomas-Chapais, borough of Mercier-Hochelaga-Maisonneuve
- Les AmiEs du boisé Dora-Wasserman, borough of Notre-Dame-de-Grâce-Côte-des-Neiges
You can also create your own group in your neighborhood and contact your borough to propose a project. Encourage young people to take part: they’re dynamic, motivating and creative!
This project has been made possible in part through a financial contribution from the Société des amis du Biodôme.
- LAVOIE, Claude. 50 plantes envahissantes : Protéger la nature et l’agriculture. Les Publications du Québec, 2019, 415 pages.
- Site Internet du Service des grands parcs, du Mont-Royal et des sports.
- Sentinelle : Outil de détection d’espèces exotiques envahissantes, MDDELCC.
- Nature-Action Québec, Connaissez-vous le nerprun?
- Invasive Common (European) Buckthorn Best Management Practices in Ontario (Rhamnus cathartica).