Large trees have a tremendous impact, both ecologically and economically. Why wait decades for smaller trees to mature when we can already enjoy the benefits that large trees provide today? For urban areas, choosing large trees means investing in a healthier living environment right away. And we shouldn’t only think in terms of numbers, but in terms of crown volume—the future green canopy of our cities. The larger the leaf volume, the more functions a tree can fulfill simultaneously.
The Green Effect
“The bigger the tree, the greater its effect on its surroundings,” explains Marie-Ange. “More and more studies show that it’s not trunk size but crown volume that determines a tree’s contribution to the climate and a healthy living environment. Large trees perform more functions at once. They store more CO₂, provide more shade, improve air quality more, enhance biodiversity more, and retain more water during drought. One tree can be more valuable than twenty small ones—though of course, we should not lose sight of species diversity.”
3-30-300 Rule: Green Close By
To assess green quality, more and more municipalities are shifting from counting trees to calculating crown volume. Beyond their ecological value, large trees also meet people’s need for greenery in their surroundings. They are landmarks and fixed elements in the landscape. To promote a healthier living environment, the 3-30-300 rule has been introduced: every home has a view of at least 3 trees, every neighborhood has 30% canopy cover, and no one lives farther than 300 meters from a park or green space. This approach improves human health and well-being while encouraging the choice for large trees.
Expertise and Benefits
Planting large trees in public spaces provides not only immediate benefits but also long-term ones. Municipalities invest in decades of expertise. Formative pruning—often difficult in public areas—is no longer needed, and the required trunk clearance for traffic is already achieved. Critics point to higher purchase, transport, and planting costs, as well as the assumption that large trees establish less successfully. Marie-Ange counters: “A well-prepared large tree has just as much chance of establishing as a small one. On the nursery, we regularly transplant trees, ensuring enough spacing for the crowns. We carry out both formative and root pruning and ensure a good balance between crown and root volume. It’s not only about expertise but also about buying time. This is a major advantage for municipalities needing landmark trees or trees with tall trunks, as well as for garden owners who want a mature look without having to wait years.”
Choose Big, Choose Green
Large trees not only provide ecological benefits but also increase property values by 4 to 15%, according to research. The software program i-Tree even translates the value of trees into monetary terms, making the economic benefits of greenery even clearer. The conclusion is simple: large trees have a tremendous impact, both ecologically and economically.
