Naturespeak

East is east and west is west, and that’s why the maple leaf is red

By Bob Brett,

Whistler Naturalists

Autumn is here and resistance is futile. Nights are colder, days are shorter, and swimmers at the nude dock on Lost Lake are fewer and goosebumpier. Look closely, and you’ll even see yellow tinges on the cottonwood leaves.

Yellow tinges. Not gold, and never orange or red. Even at the height of fall, local cottonwoods and alders add only small dashes of colour to Whistler’s hillsides. For a proud Canadian steeped in the images of Tom Thomson and the Group of Seven, something’s missing.

Back east, autumn’s brilliant oranges and reds inspire artists, poets, and tourism marketing boards. That’s why you don’t need to be Dudley Doright to deduce the red maple leaf on Canada’s flag was chosen by an easterner. Especially since the stylized leaf represents a sugar maple, a tree famous for turning fiery red in fall and not often found west of the Ontario-Manitoba border. (There’s a historical irony in the truth. The maple leaf was first adopted as the symbol of Quebec’s nationalist St. Jean Baptiste Society in 1834.)

Without the east’s colourful mix of maple, birch, beech, and oak, autumns in the Coast Mountains aren’t notably picturesque or paintable. In fact, with the exception of the cottonwoods and alders (and some planted aspens and eastern maples), things here look pretty much the same year-round. The conifer-dominated forests remain evergreen.

So what gives? Why are our forests so dominated by conifers? The answer is complex (another way of saying I don’t know for sure) and combines geology, glacial history, soil, and climate.

The Coast Mountains are comprised mostly of acidic bedrocks, especially granites and granodiorites. Acidic rock and recent deglaciation result in young, acidic soils (mainly Podzols) which favour conifers over deciduous trees.

But there’s a chicken-and-egg aspect to this explanation. What came first: acidic soil, or plants causing acidic soil? Our two dominant plant families, the pines and heaths ( Pinaceae and Ericaceae ), both thrive on acidic, low-nutrient soil. Both also produce nutrient-poor litter which acidifies the soil. In contrast, deciduous trees produce leaves which tend to reduce soil acidity and increase soil nutrients.

Our climate also contributes to the dominance of conifers. Whistler skiers are intimately familiar with wet snow measured in cementimetres. The rain-soaked snowpack develops early and insulates the ground from freezing. Unfrozen soil allows conifers to photosynthesize while deciduous trees are leafless. In spring, a conifer can start photosynthesizing even while its base is covered by snow.

Whatever the exact cause, we are rich in conifers and poor in deciduous trees. And the west’s conifer-dominated mountains apparently didn’t impress the Group of Seven much. When some of the Group, justifiably famous for their faithful representation of the beauty and warmth of eastern fall colours, visited the Rockies in the 1920s, they painted a cold and remote place. Just check Lawren Harris’ stark, foreboding shapes rendered in cool blues and whites, dark greens, and black.

We obviously view our mountain landscape differently. And, though the display is more subtle, our so-called evergreen forests offer a fall beauty of their own. Here it’s the shrubs that provide most of the colour: huckleberries, dogwoods, and a host of other species dapple crimsons and oranges into forest openings, subalpine meadows, and streambanks. And even though our autumn landscapes never graced the canvasses of the Group of Seven, that needn’t stop you from toting your palette and easel into the woods to create your own Canadian classic.

Upcoming Events:

Websites of the week:

Here are two ways to see Lawren Harris’ paintings in colour. Click on http://arts.risjak.net/pictures/ or www.virtualmuseum.ca/English/Gallery/.

Sightings and Memberships: NatureSpeak is prepared by the Whistler Naturalists. To become a member or to report noteworthy sightings of mammals, birds, or other species, contact Lee Edwards (905-6448; e-mail: leighe11@hotmail.com).