COLUMN: Planting trees for Earth Day an act of climate defiance

The sugar maple (Acer saccharum) isn’t just the heart of our forests — it’s the soul of Canada.

A cornerstone species in Ontario’s woodlands, this towering giant supports wildlife, stabilizes ecosystems, and lives for over 200 years. It’s no wonder the sugar maple inspired our national flag—it’s strength, beauty and legacy all in one leaf.

There’s a quiet rhythm to the seasons here in Simcoe County, but if you’ve been paying attention, you’ll know that rhythm is starting to skip a beat.

Our forests have been under siege. Initially, the gypsy moth (now rebranded as the spongy moth) cycled through, turning once-lush canopies into delicate lacework. Soon after, the emerald ash borer—a jewel-toned  invader—swept in, leaving entire stands of ash trees ghosted and hollow. And just this past winter, a  catastrophic ice storm snapped limbs and hearts alike, shattering trees like fragile glass and leaving many of us  questioning what true resilience looks like in our changing world.

This Earth Day (April 22), I don’t want to simply mourn what we’ve lost. I want us to plant what we still can. Because in the face of these intensifying challenges, planting trees has become more than a nice thing to do — it’s an act of climate defiance, of future-building, of love.

With climate change speeding up, long-term survival will become tougher for trees. We will be looking for species that can survive winter snow, wind and ice storms, plus summer heat and drought. I will recommend native trees here because they usually provide more food for struggling pollinators and local birds than mass-produced trees of foreign origin do.

As our climate continues to warm, not all trees will be able to adapt. Several species currently common in the Lake Simcoe watershed are approaching the southern edge of their natural range, and many are beginning to show signs of stress.

These are our retreating species — trees more closely tied to cooler, boreal climates that are struggling with increased heat, erratic weather and shifting precipitation patterns.

Species such as white spruce, balsam fir, eastern white cedar, paper birch, tamarack and trembling aspen may still be familiar on the landscape today, but their long-term viability is questionable. In the coming decades,  we can expect reduced growth rates, shorter lifespans and a decline in natural regeneration. 

I’ve personally witnessed the toll these changes are already taking. After the most recent ice storm, my eastern white cedars, weeping willows and wild apple trees suffered the most extensive damage.

Branches snapped like matchsticks under the weight of ice, leaving twisted limbs and splintered trunks in their wake.

While weeping willow isn’t native and already struggles with storm resilience, the damage to the cedars — once considered a hardy, reliable choice — and the breakage in my wild apple trees were clear signs that even our old standbys are no longer guaranteed survivors in a climate-shifting world.

For landowners, gardeners and community planners, this is an important moment of reflection. While these trees still have a place in shaded or protected microclimates, planting new ones at scale may no longer be a wise investment. Instead, we can honour their legacy by transitioning toward species better adapted to the changing future.

Enduring Species: Holding Strong

These species are part of our temperate forest heritage and are expected to maintain — or even increase — their  presence across Simcoe County and the Lake Simcoe watershed.

These are your safe bets — ecologically valuable, resilient and adaptive.

The sugar maple, with its blazing fall colours and syrupy legacy, remains a favourite. It’s not just a beautiful shade tree, but a resilient species that can handle our shifting seasons. Red and silver maples bring fast growth  and adaptability, especially in wetter soils.

Among the oaks, white, red and bur oak all stand tall as ecological heavyweights. Their acorns feed wildlife, their canopies host countless species and their deep roots make them remarkably storm- and drought-tolerant.

Red oak tree/Derrick Mayoleth photo

American beech adds elegance to our forests with its smooth grey bark and golden fall glow, while White Pine, Ontario’s provincial tree, continues to be a symbol of strength and softness in every breeze. And then there’s black cherry, whose spring flowers support pollinators and whose fruit feeds birds — a tree that  gives in every season. 

American basswood is a true pollinator magnet, cherished by bees for its sweetly fragrant summer blooms, while its broad, leafy canopy casts a soft, cooling shade across the garden.

Advancing Species: Tomorrow’s Forest Arrives Early 

As the climate of southern Ontario creeps northward, so too does the Carolinian forest zone, bringing a rich  diversity of new species that may soon find suitable conditions in the Lake Simcoe watershed. These trees, once limited to the extreme south of the province, are now emerging as viable options for those looking to plant for long-term resilience and biodiversity.

The southern oaks are also moving in, bringing with them resilience and beauty. I especially admire the swamp  white oak, which thrives in wetter soils and tolerates both urban stress and climate extremes. Chinquapin oak is another standout — a sweet-acorn-producing tree with an understated charm and a preference for dry, limestone-rich soils. For bold fall colour, scarlet oak is hard to beat, while eastern black oak offers both beauty and adaptability to poor, sandy soils.

Tulip tree is another favourite of mine — fast-growing, graceful and dressed in bright green, tulip-shaped leaves  with striking yellow blooms. It’s a pollinator magnet and always a conversation starter.

Tulip Tree/photo courtesy Fred Nims

Then there’s American hornbeam, sometimes called musclewood for the sculpted look of its sinewy grey bark. This underused gem brings a symphony of fall colour, textured foliage and year-round elegance  — making it an ideal choice for shaded gardens and naturalized spaces.

American Hornbeam/Henryk Niestrój photo

But here’s the golden rule: Diversify. One thing nature keeps teaching us—often the hard way—is that monocultures are sitting ducks. Biodiversity isn’t just pretty, It’s our buffer and protection. A mixed forest is a resilient forest — and the best investment we can make in a changing world. 

Cheers to the trees — Plant them wisely. Love them deeply. The future grows from here.

Monika Rekola is a certified landscape designer and horticulturist, passionate about gardening, sustainable living and the great outdoors. Contact her at [email protected].