We’ve all seen trees in the city that seem to be devouring their surroundings. What’s really going on with these “hungry trees”?

 

Hungry Trees first caught my attention during a trip to Montreal, where I saw signs near certain trees that read, "Arbres Gourmands". In French, a 'gourmand' is someone who greatly enjoys eating, and a polite way to refer to someone who over-indulges. Whoever hung these signs seemed to be gently ridiculing the trees.

 

 a tree that appears to be eating a length of cord

 

Years later, I realized the term 'Hungry Trees' misreads what's happening with these trees; they aren't at all hungry for sidewalks, fences, or anything of the like.

As a tree grows taller and its crown grows fuller, the trunk ― which is the pipeline between the leaves and the roots ― must be able to transport more water and nutrients. For that reason a growing tree will grow a wider trunk.  A tree will engulf whatever's in the way of its widening trunk, but that's merely a side-effect of its primary goal: accessing more resources to fuel its growth.

 

a tree trunk enveloping some disused posts placed too close to its trunk

 

Understanding apparently hungry trees this way means it's no longer the trees that deserve ridicule; rather, it's us. Tree trunks grow wider over time. If we don't leave space to anticipate this growth, we are building short-sightedly or in ignorance of how trees work.

 

tree roots are mostly near the surface, spreading far beyond the width of the crown

 

Instead of saying "hungry trees" we should call them "confined", "restricted" or "cramped trees". ​​

Though trees can be massive, they're delicate. Especially at the very base of the trunk, where you'll find the trunk flare, the area of the tree that often winds up cramped for space. The 'trunk flare' is the zone where the major lateral roots meet the trunk― a highly delicate part of a tree's anatomy since the roots are like main arteries. Damage here can jeopardize the entire organism.

 

a tree trunk growing into a fence

 

Trees work wonders for any city or built environment. We would be wise to plan for their longstanding health. As you encounter cramped trees on your next walk, take that tree as a lesson in poor planning, and don't make the same error.

If you’re interested in getting advice on how to plant the right tree in the right place and ensure it has ample room to grow, check out LEAF’s Backyard Tree Planting Program.

 

planks of wood placed between two tree trunks as a bench are now cutting into the trunks and causing damage

 

Jonathan Silver is a guest blogger and volunteer photographer for LEAF. He enjoys exploring built and natural places by foot, bike, ski, and canoe. Working as a wilderness guide, he developed a passion for nature. He now works towards solving environmental problems by closing the experiential gap between our actions and their effects ― an interest that started during his MA in Philosophy at the University of Toronto. You can see more of his work at JonathanSilver.ca and @silverjonsilver