Not long ago I wrote
Let me expand on that. It’s easy to take them for granted, but trees are an inherent and necessary part of our landscape. As grasses are to the prairies, trees are to here. When the first Euro-Americans moved out here they were utterly gobsmacked at the forests they found. A tall tree back East was 100-feet tall, a big Yellow Pine is 2-feet across. The ‘big four’ native trees- Douglas Fir, Western Hemlock, Western Redcedar, and Sitka Spruce will each top 200-feet high in ideal conditions. The Western Redcedar is the biggest tree in America other than the Coast Redwood and the Giant Sequoia, getting up to 19.7 feet across (The Kalaloch Cedar), and the Douglas Fir is reputed to top 400-feet, which would make it the tallest living thing on Earth!
The Redcedar is considered sacred by local natives, and every part of
it is or was used, the wood for structures, boxes, canoes, paddles, and
everything else you might expect, the bark for cloth, rope, and even emergency food, the roots for fabric and medicine, the branches for… you get the idea. It is thought of as a life-giver, and one is required to pray to the spirit of the tree to ask permission to use its substance and thank the tree for it.
Douglas Fir is the classic lumber tree hereabouts, and can crack 300’ in height. Unverified story has it that a grove in Seattle in what is now Ravenna Park was 400’ tall, but when the private park was given to the city somehow all those trees had been logged before the city officials arrived! Structurally, it is considered equivalent to Western Hemlock, Washington’s State Tree. The Uniform Building Code runs their two listings together as “hem-fir”.
Bigleaf Maple is among the most common deciduous trees here. It grows well in our soils, but isn’t used for structural purposes because it cracks and fractures easily. Years ago I was in my aunt’s back yard on a sunny summer day facing a neighbor’s Bigleaf and a massive branch- perhaps 20 percent of the whole tree- just fell off! Luckily, no one was hurt and it missed a car parked in that alley.
Black Cottonwood, common around stream edges, is tall and beautiful, but the pioneers knew it as “rottenwood” because it is brittle and subject to falling over. It fills the late spring air with “cotton” (seeds).
Red Alder is usually the first species to fill in any place disturbed by fire, landslide, or construction. “Live fast and die young” seems to be its motto, as they rarely live over 150 years and most go much younger. It was seen as a “trash tree”- one which had no commercial value itself and could interfere with high-intensity logging- for decades, but is valued now for cabinetry work and for smoking salmon.
Pacific Madrone is a favorite of mine. With its big, glossy, evergreen leaves and peeling red bark it looks like some exotic from the tropics, yet it’s as native as the Redcedar. On a sunny slope it might grow fairly straight, but it will take whatever course it must to get into the light, so it can often end up
twisted and highly picturesque.
Trees are essential habitat for most of our native life, and essential environment for the rest. Salmon don’t live in trees, obviously, but the trees provide the shade necessary to keep the streams cool enough for salmon and when the salmon die, especially when bears and eagles take the fish into the forest to eat, they return massive amounts of nutrients to the trees. UW researchers have studied tree rings to get a clearer view of the size of salmon stocks in the pre-contact age so we can better rebuild their runs.
‘Doug-fir’ is habitat for Red Tree Voles, Spotted Owls, and Porcupines, and food for many birds, and its base will be surrounded by Vine Maple, Salal, Oregon Grape, various ferns, and Huckleberries. Redcedar dominates large swaths of our area and feeds many animals, especially in winter. Every one of our trees is its own ecosystem. Removing any of them is to affect all of them. They are all just parts of the whole.
Trees take up vast amounts of carbon as they grow, hence the idea of , and vast quantities of water, hence a good part of why they’re so good at controlling runoff. The other aspect of their part in runoff control is the simple physical presence of their roots keeping soil particles in place like a net. The US Forest Service says “The planting of trees means improved water quality, resulting in less runoff and erosion. This allows more recharging of the ground water supply. Wooded areas help prevent the transport of sediment and chemicals into streams.”
A mature ‘climax forest’ here is a patchwork of Doug Fir, Hemlock, Redcedar, Spruce, and others, as all their different environmental requirements, growth patterns, and random chance variably favor one or the other over the centuries. It adds up to the greatest amount of biomass in the world and we must preserve, repair and expand it wherever it exists. Amazonia and the Great Barrier Reef may have greater diversity, but in sheer mass our forest ecosystem is the greatest on Earth.
The City of Shoreline has a goal to increase the city’s tree canopy. While higher CO2 rates will foster faster growth in some trees we can’t count
on that alone to offset our impacts. At the very least we should plant more trees! Some folks won’t consider all those other aspects of trees, despite that they will have large positive effects on homes and neighborhoods as well. King County has a good list of native plants and their landscaping characteristics. Knowing all that I have to say it really hacks me off when someone can’t see a tree- any native tree- as more than just an interchangeable “design element”!