Pacific madrona -- Arbutus menziesii
The drive is short but not exactly direct. On roads that hug the coastline, you don’t usually go straight from point A to point B. As we wind along on this autumn afternoon, we catch glimpses of rich blue water sparkling under the sun. All along the shore are gnarly Pacific madronas (Arbutus menziesii) with their orange-red bark and waxy evergreen leaves. They are the dominant plant along the shoreline and this is the first time I have seen these great trees in all their glory. We’re on Orcas Island, the largest of the San Juan Islands group clustered together in the Salish Sea between the Straits of Georgia to the north and Juan de Fuca to the south. Having just driven off the ferry from the mainland, we’re on our way to a trail. We’ll be there soon but in the meantime I’m glad to be in the passenger seat and not worried about watching the road.
Madronas have without question the most spectacular bark of any tree that grows in Washington. Their exfoliating bark becomes lighter with every layer that drops to the ground. The outermost layer usually covers the lower portion of the tree to provide scant protection from fire. This layer is inconspicuous enough; a roughly textured reddish-grey that looks like any number of other species, almost anonymous. But underneath this protective layer is very unusual bark. A smoother paper-thin layer of cinnamon, or terracotta, or russet, or ochre is exposed as the outer bark falls away. Some type of red-orange-yellow-brown, a name I obviously can’t pin down. Whatever named, it is lovely. And more: beneath this middle layer, as that peels away and falls to the ground, is the even smoother inner layer of bark. On the most recently exposed sections, the color here is something between lime-green and chartreuse, a really fresh and delicate green-yellow color that feels like spring. This inner most layer is the most variable in color, and as it ages the colors deepen to orange and red. Running your hand over the inner layer, it almost feels skin-like. The Kwakwaka’wakw, who live on what is now Vancouver Island call them xaxanaʔəәms, meaning “naked trees”. What a fun and appropriate name. And as the tree undresses itself, each bark layer is nice but what is really special is the harmonious and unique color combination of all three layers together. Madronas are one of the defining characteristics of the landscape through the Salish Sea and Puget Sound, instantly evoked in the mind, and it’s all because of the bark.
In truth, just about every aspect of a madrona is visually engaging. In summer the creamy white flowers, tiny bells just beyond the leaves, cover the tree. These flowers attract hordes of bees and hummingbirds, buzzing along the shoreline from tree to tree. By late autumn, the branches are laden with interesting fruit. They are shiny red orbs and covered with tiny bumps, reminiscent of a kickball from elementary school recess. On the end of each branch, buds which promise new growth are a delicate rose color. So too the petioles which attach the oblong, waxy green leaves. A midvein of a paler tone prominently bisects each leaf. The underside of the leaf is glaucous-green to silver. On a clear windy day, looking up at a large madrona is mesmerizing. Strong gusts of wind blowing off the water causes the leaves to shimmer, flickering between shiny green and abaxial argentum. Against the blue sky it is dizzying.
In the San Juan Islands and along the Puget Sound, madronas frequently grow at the edge of the coastal cliffs and shoreline at severe angles in order to escape the shade cast by their forest companions, the ramrod straight Douglas-firs (Pseudotsuga menziesii) towering above. Their twisting limbs sometimes snake right along the ground or picturesquely stretch out beyond the edge of land. There is something appealing and familiar about them. Sinuous and rippling arboreal forearms reaching out from the forest, grappling for sun, for life, making their own space, rooted in the land but hanging in midair above beach and water. The strength of these outstretched trees is amazing, like holding a heavy weight with arms fully extended in front of you forever. They achieve this through well anchored roots and strong but flexible wood.
Conversely, the occasional madrona on the edge of the forest or in an open field achieves great height with a massive crown and single stout trunk nearly buttressed at the base. These two specimen types are the vision of what madronas can look like where they grow without competition from taller trees. But in Washington, they seem to be the exception to the rule. In the wild, you most commonly see tall skinny madronas with small crowns, ungainly and somewhat awkward looking. These are the madronas of the forest and their form reveals a desperate attempt to catch some sunlight high above. The great variation in form is interesting and on a trail along the coast we pass through a small thicket of tangled madrona limbs not a hundred yards away from a stately mammoth of a madrona that must be 60 feet tall. Just beyond the massive tree, back in the forest, gangly madronas reach out among Douglas-firs. All three forms within sight of one another here in the heart of Washington’s madrona country.
Madronas almost feel out of place in western Washington. In this state of foreboding evergreen forest, their exuberant color and exfoliating bark feels so Californian. But of course they are Californian, where they are called madrone with an “–e”. And they’re also Oregonian. In fact, they span much of the west coast from Vancouver Island to the San Francisco Bay, becoming less frequent through southern California. Although most at home along the coast, they do venture inland to a small extent with isolated populations near Mount Rainier and along the Columbia River in Washington. In California, their inland intrusion is most pronounced with a substantial population in the foothills of the northern Sierra Nevada. These inland populations take hold where conditions are similar to their preferred coastal habitat, areas protected from extreme winter cold but open and with thin soil that makes growth difficult for other large trees.
We sometimes associate drought tolerant plants with toughness. From a garden-centric view that assumes normal plants need scheduled fertilizing and incessant watering, madronas are tough. They like to be left alone in the heat and drought of summer, thriving where a hydrangea would die a thousand deaths. The reality though is that madronas are feeble plants that have a hard time dealing with anything other than their interpretation of ideal conditions. They are incredibly sensitive to standing water around their roots, mycelial disruption, and landscape alteration. These things weaken the plants and give advantage to the remarkable number of pathogens that can affect madrona health and even kill them.
Basically, madrona health is incompatible with the typical human land development. First, bulldozers and builders alter the landscape, removing vegetation, changing topography and hydrology, and compacting the soil. Next, homeowners overwater, over fertilize, and use pesticides. These things negatively impact the finicky madrona. In Washington, the madrona population has declined over recent decades. Like all things in nature, the exact reason is probably a combination of factors too complex to fully decipher but for an obvious starting point, look no farther than the fact that prime madrona habitat is also valuable waterfront real estate.
Madrona bark is undeniably beautiful, but I wonder why it should be. What purpose does it serve for bark to be so colorful? Would other non-exfoliating trees also be this colorful if their inner bark layers were exposed? I think not. For every colorfully exfoliated madrona and rainbow eucalyptus (Eucalyptus deglupta), there is a shagbark hickory (Carya ovata) and paperbark birch (Betula papyrifera). Both are beautiful as well, but lack the array of color. Maybe there is some evolutionary purpose, some hidden agenda of which I am not aware. Does it help pollinators or seed dispersers to locate the trees? That might be possible but seems like a stretch. Maybe madronas are colorful for no reason at all. After all, it’s good if we live in a world where some things are just randomly and pointlessly nice.