The Magic of Maples – Why the Maples in Pacific Spirit Park are so special

Vancouver is the land of the giant evergreen tree. Our Douglas-firs, Hemlocks, and Cedars. They dominate our forest, towering over and casting such a deep shade that few plants can grow below. There is really only one deciduous tree species that can compete. This our national tree, a Canadian icon, our stunning Maple Tree.

Bigleaf Maple Leaves

There is an important distinction to make between coniferous, needle-leaf trees (Gymnosperms, which means ‘naked seeds’, think trees with cones!) and broadleaf trees (Angiosperms, ‘covered seeds’, think apples, cherries, or nuts). We often think of both of these groups under the same classification of “trees”. When really, Gymnosperms vs Angiosperms is like Insects vs Mammals. While they both have wood and leaves, the structure of the wood and leaves is actually radically different between the two groups. It can be misleading to talk of both as trees because they are so fundamentally different.

Gymnosperms are almost twice the age of Angiosperms in evolutionary time. Gymnosperms are ancient dinosaur trees while Angiosperms really only came into their own with the rise of the mammals and extinction of dinosaurs. Douglas-firs are ancient elders and Maples are punk kids encroaching on their territory. Gymnosperms were used to a world of less CO2 and water, so learned to grow as efficient as possible. With a wood structure that uses as little water as possible, and needle-leaves that are durable and last for multiple years. Angiosperms are short-lived, flamboyant showboats in comparison. They often lose and regrow their leaves every fall, requiring a large amount of water and CO2 for this incredible production. They also spent a lot of energy on beautiful flowers and tasty carbohydrates (fruit!) to attract animals and insects for pollen and seed spreading.

When you walk in the woods though, the easiest difference to see between the two is how angiosperms are sun-chasers, putting branches out in every direction, grabbing as much sun energy as possible. Gymnosperms trunks grow straight and true with small branches, their more efficient wood structure meaning they need less sun.

Angiosperm vs gymnosperm shapes

Often on my tree walks I focus on the identifying the three main gymnosperm trees of Pacific Spirit Park (Douglas-fir, Cedar, Hemlock). People learn to identify these trees by their bark and it quickly becomes easy to tell which is which. So then I try and make it a bit harder and point to a new tree and watch as they struggle to guess what it is. It’s bark looks a bit like Douglas-fir, no wait more like a Hemlock. Hmmm. They get stuck, doubting themselves.

Then I encourage them to look up. And quickly they see how this tree has huge branches growing out to sides near the top of the trunk. It is not a straight and true gymnosperm. It is the only tree that can compete with the dense shade and height of the gymnosperms. It is a Maple! One of of biggest native maple species. The Bigleaf Maple (acer macrophyllum).

Maples! What incredible trees. They have fascinating survival tricks. They have very wide leaves, where other broadleaf trees mainly have leaves longer then they are wide, maples have the opposite. Wide leaves gives them the ability to grow better in the shade, spreading to catch more sun.

Maples also have more long pointed edges, ‘drip tips’, then other trees do. Using the all-important and almost-paradoxical feature of water know as cohesion (where water molecules will stick together and stick together better on smaller surfaces), these tips allow maples to hold water on their leaves during rain fall and release it slowly. As any hardcore Vancouverite walker can attest, maples are a great tree to take cover under during a rainstorm, but a terrible one to be under just after the rain has finished.

Maples leaves also have an incredible ability to change their size and thickness based on their location on the tree to fully exploit the sun they get. It gives them great shade tolerance. Next time you are walking past a maple, look at how the leaf stems (the petiole) of leaves vary. Stems can be super long or very short, depending how much they length they need to reach the sun.

I could keep going with the fascinating properties of maples! But just one more! Their wood! Maples can produce some of the strongest wood in North America. Our world-famous Sugar Maple (acer saccharum), on our flag and known for Maple syrup, is also know as Rock Maple for the strength of its wood.

Our biggest native BC Maple, the BigLeaf Maple, the one that can compete with the evergreens, was known by indigenous tribes as the “Paddle Tree”. Paddles were an all-important tool for costal tribes. Getting paddle wood from douglas-fir or cedar meant a weaker paddle, one that would soon bend and warp under the tension of human and water resistance. Bigleaf Maple wood would not bend, it was renowned for its strength. It still is! Bigleaf Maple Trees often get poached – harvested illegally – because its incredibly strong wood is so rare in our west-coast forests.

Bigleaf Maple is fitting named so because of its massive leaves. One of the, if not the, biggest leaves in Canada. I’ve seen leaf stems as long as arms. These giant leaves reach over conifers to steal the sun. The deep lobes in the leaves allow them to bend away from the sun and wind when it gets too extreme that high up in the canopy. The strong wood of the Bigleaf allows them to put out massive side branches that also help outshade smaller conifers.

These massive Bigleaf branches are often covered with moss and ferns, creating its only ecosystem, a mini-forest in the air. It’s become a big new area of scientific exploration, these aerial-canopy forests, a whole world existing unknown above our heads. You won’t see as many moss or ferns on conifers, their straight trunks means water runs off too quickly and plant roots can’t hold on. The deep curves, the sideways-growing, of maple branches is the perfect home for these canopy species and shows off the strength of maple wood, holding them up.

In last couple decades it was also discovered that Bigleaf Maple produces aerial roots. Small roots that grow out of the trunk and into the moss and fern ecosystem, allowing maples to capture some of water and nutrients that are held there. It’s a symbiosis, they exist together and support each other.

Bigleaf Maple isn’t the only native maple you will find in Pacific Spirit Park forest. Far below the canopy of Bigleaf you’ll find the underappreciated Vine Maple (acer circinatum). Vine Maples are small trees that have evolved to become experts in living in shade. It does what I like to call ‘aerial acrobatics’ where it will grow sideways and trunk will do 180° turns. All to get whatever piece of sun it can. Often other bigger trees will fall on the Vine Maple and force it to the ground, where it will grow out some roots, reestablish itself, and then keep growing sideways.

As you can probably guess from this, Vine Maples also have extremely strong wood. Stronger even then the Bigleaf. So much so, that Vine Maple was known for being used by indigenous tribes for tools we now use metal for, like nails. Vine Maple wood is so strong, that it is almost too strong to be used in wood construction. Well, that combined with the fact the trees are very small and so you don’t get long planks of wood like you do with Bigleaf.

This ability to put out roots from the trunk though, known as “Layering”, make Vine Maples become maze-like in how they grow through the forest. Often you think you are looking at separate trees and then you realize there is a branch connecting between them and they are the same tree (Branch? Trunk? No real difference for Vine Maples) .

The most fascinating part of the Vine Maples, and their distinguishing feature, is that their bark is green. Their bark can photosynthesize just like their leaves can. This what really makes them forest floor experts. It’s why they can grow sideways and still survive. They use every ounce of sun they can find.

I hope I’ve convinced you what incredible species Maples are. I encourage you to walk through Pacific Spirit Park (PSP) and follow the twists and bends of Vine Maple. To look up into the canopy and try catch a BigLeaf Maple and look at the moss-forest growing on it.

There’s more to know with Maples. Lately PSP has seen an invasion of European Maples which have been widely planted as street trees. These maples, the Norway and Sycamore Maple, are adaptable, hardy species that are starting to replace Bigleaf and Vine in the more open areas of the forest. Norway and Sycamore are generalist species that are better adapted to high temperatures caused by climate change. Plus they have an massive seed source of well-watered street trees.

For Canada Day, I’ll be leading a Maple Tree walk of PSP to identify and discuss our magical maple trees in early July. Please subscribe to our Newsletter for updates about the date and time of this walk and other events.