It’s not often I make the acquaintance of a 1,300 year old, but this summer I found a tree on Whistler Mountain that started growing sometime around 700 A.D.
For historic perspective, sacking and pillaging were more popular than skiing in the year A.D. 700. The Dark Ages held Europe as Huns and Visigoths gave way to Arabic Muslims and the Franks under Charlemagne. It was 500 years before the Magna Carta and Marco Polo, and more than 600 years before the first light of the Renaissance began to flicker in Europe.
Up on Whistler Mountain, the forest must have been pretty quiet.
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Fast forward to the dawn of the modern era, 100 years ago. Whistler’s forests were mostly untouched by humans, other than by the trails and seasonal settlements of the Lil’wat and Squamish people.
The railway’s opening in 1914 changed things. It brought settlers to the area and helped Myrtle Philip build Rainbow Lodge into the most popular resort west of Jasper. For a couple of decades, the forest remained mostly intact, except for farm clearings, the occasional railway fire, and some minor logging. Then the era of industrial-scale logging began. Sawmills sprung up at Parkhurst, Lost Lake, and along the railway. By mid-century, some serious dents were being made in the forest. By 1970, loggers had cut the majority of original forest up to mid-elevation on the mountains. The pace of logging slowed, but then another wave of resort development picked up steam. In the 30-something years since, more old trees have fallen for housing and golf courses and ski runs. And they continue to fall.
I couldn’t help wondering what the forests were like before the railway was built. I wanted to know their age, their origin, and what they’d been through over the centuries. Too bad so many of the old trees were hauled down to Squamish and beyond. I could have asked them.
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That 1,300-year-old tree, a yellow-cedar, was one of 500 I sampled while researching Whistler’s forests for the municipality. My plan was to go to forest stands throughout the valley to find out their age and what disturbance created the conditions that allowed the oldest trees to start growing. Was it a fire, flood, landslide, insect outbreak, fungus, windstorm, or something else?
Fire was the main disturbance type I expected to be able to quantify. When a big fire burns through a forest it kills many or all of the canopy trees. A burned site is colonized by pioneers – fast-growing trees that require full sun. Douglas-fir is the main pioneer in our area at lower elevations; pines and cottonwoods are others. Whenever you see them, you can assume a past disturbance opened up the forest canopy enough to let them establish.
You can learn about past fires in a few ways. The best way is to use fire-scarred trees. With precise dating of their annual rings, you can pinpoint the exact year a fire burned, even the exact season. Unfortunately fire scars are pretty rare in Whistler, compared to dry areas where fires are more frequent and less severe.
You can also use carbon dating of the charcoal, if you have deep pockets. Each sample costs $500 to analyze, and that expense can burn through a research budget pretty quickly.
The method I used most was stand age reconstruction. This method is based on the premise that the canopy trees in each stand originated from the same fire and should be approximately the same age. If you have samples from throughout the valley, you can then reconstruct which areas burned in the same year, presumably by the same fire.
I aged trees by counting their annual rings. To get the rings, I took core samples of the biggest pioneer trees on each site plus a representative sample of surrounding trees.
All told, I cored trees in 62 places from valley-bottom to treeline including Rainbow Trail, 7th Heaven, Cut Yer Bars, Lost Lake Park, Peak to Creek, Blueberry Hill, Cheakamus Lake, and Singing Pass. I sampled every well-known tree I could get to, like the big spruces at the bottom of Lorimer Road and at Meadow Park Sports Centre, the curved Douglas-fir below Chateau du Lac, and the big Douglas-firs behind Spruce Grove.
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To core a tree, start with a hollow boring tool. First screw the borer, as low as possible, into the tree and continue turning until you are more than halfway through. Next, take a cup-shaped extracting tool and very, very carefully pull the core out. This is the part I like best, the part most like opening a Christmas present. I never know what’s inside until I pull it out.
With luck, the pencil-shaped core is in one piece and goes right from the outside bark to the middle of the tree, or pith. Usually I’m not so lucky.
Missing the pith is an occupational hazard of tree coring, but since the pith is the most important part of the core you have to try again. My ethical maximum is three tries. Any more holes and it starts to feel as though I am making the tree into a big dribble glass.
Rotten or hollow trees provide imperfect cores. Unfortunately, rot and hollowness are characteristic of the oldest trees, the ones with the most history. Without the innermost rings, their history is incomplete.
Perhaps the biggest challenge is a core that breaks into little shards as it comes out of the tree. Now you have a handful of little pieces in the transporting straw, all jumbled into random order. They’ll remain that way until you try to unravel their proper order while gluing the pieces onto a grooved wooden mount.
After all the cores are mounted, sand them to a mirror finish so the annual rings stand out. Then turn on CBC Radio and set up a good microscope. Get a good one so you can see the really thin rings, some so narrow 100 fit into the width of a little finger.
Label the sampling year at the bark end of the core, then count back through the decades and centuries. Back past the opening of Whistler Mountain, back past Rainbow Lodge and the railway, and back into the unrecorded history of Whistler’s forests. Back past 1900 and 1800 and 1700. Maybe back past Columbus, the Renaissance, and the Magna Carta.
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After many hours with the CBC and my microscope, I have learned quite a bit from the trees. The biggest challenge has been the number of cores that are incomplete due to rot. That said, here are my results so far. Please keep in mind that the dates I mention are only accurate to within a few years.
Our unlogged forests are old
With two main exceptions, virtually all unlogged forests date back over 300 years. The first exception is the spruce-dominated valley bottom where flooding has affected the forests more than fire. These trees grow fast and die relatively young. The second exception are the lodgepole pine sites on rock outcrops. I sampled two: the four lane section of Highway 99 by Brandywine and the outcrop uphill of the highway at the north end of Emerald Estates. Both dated to the late 1800s.
Size is misleading
Big trees aren’t always old and small trees aren’t always young. For example, the biggest spruce at the bottom of Lorimer Road is two metres across and only 200 years old. The huge spruce between Meadow Park Sports Centre and the River of Golden Dreams is only 160 years old. On the other end of the spectrum, 1,000-year-old yellow-cedars don’t get much wider than one metre. On average, spruces grow about 10 times as fast.
Most Douglas-fir forests date back to the 1600s
Most of our Douglas-fir forests burned in the 1600s, though some trees survived those fires. The most intense fire activity recorded in the tree rings is between 1650 and 1700. Similar dates have been reported from forests throughout the Pacific Northwest.
One grouping is from the 1650s and includes Singing Pass, One Duck Lake above Emerald Estates, and part of the Train Wreck site south of Function Junction. Given the distance between these places, it seems unlikely they burned in the same fire.
Another, much bigger grouping dates back to the 1670s. Three sites on lower Blackcomb all date to approximately 1673, and may have been part of a larger fire that also burned the Whistler Golf Course, Blueberry Hill, and Alpine 68.
On Blackcomb, the fire stopped at the slope break just below the top of the Wizard chairlift. Going up the lift, you pass big Douglas-firs on the steeper section that then dwindle as the slope flattens near the top. The 1673 (or so) fire must have burnt itself out here because there are 700 year-old yellow-cedars above that slope break.
The most recent grouping of Douglas-firs dates back to the 1690s and includes Rebagliati Park (which more likely flooded than burned), Nesters Hill, Big Timber, and Alpha Lake Park. I don’t have enough information to conclude whether these are from the same fire or not.
7th Heaven Action
The forest at the base of 7th Heaven Express and out towards Decker dates back to the 1670s and may have begun after the same fire that burned on Lower Blackcomb. There is also a very obvious burn visible from Whistler Mountain, just below Decker and to the right (southeast) of 7th Heaven. It looks like a finger and is a lighter green because most of the regrowth is lodgepole pine. It burned around 1880.
Lots of old trees have survived fires
I was surprised to discover how many trees – mainly Douglas-firs but also other species – have survived past fires. The biggest trees above Spruce Grove Field House date back to the late 1200s, the mid-1500s, and the early 1700s. Many of the smaller pioneers, like lodgepole pine, started growing after the last fire in about 1820. The Douglas-firs at the start of the Cheakamus Lake Trail originated from a fire in the early 1500s and were scarred by another fire sometime in the mid-1700s.
Evidence of Climate Change
A pulse of establishment at treeline on 7th Heaven dates to the 1860s, the end of the Little Ice Age. This uphill march of treeline is happening everywhere in western North America and may show us what to expect with continued climate change.
The Railbed and the Forest
The oldest lodgepole pines between the Valley Trail and Alta Lake near Rainbow Park date to 1913, just after the railbed was built. The railbed impounded the water to the west and dried out the wetland on the lake side enough for trees to grow.
To find a millennium tree, look for a yellow-cedar
A millennium tree is over 1,000 years old. The best way to find one is to look for a grove of yellow-cedars about halfway up the mountainside. Rainbow Trail is a good bet. It has millennium yellow-cedars as well as old mountain hemlocks, like one I cored that is 630 years old. I found old yellow-cedars halfway up Whistler and Blackcomb Mountains as well.
Yellow-cedars can also grow very old at low elevations, for example, near Lost Lake on either side of what is now Blackcomb Way. Most of the original grove was cut to build condominiums and the tops of many of the remaining ones have been removed to protect the condos. Local arborist Paul Duncan gave me a disk the size of a side plate from a tree he topped 20 metres above the ground. This is not a fast growing tree. It has 550 rings even that high up the stem.
Whistler’s oldest documented tree
The oldest tree I found was a yellow-cedar on Whistler Mountain. It was at the bottom of a gladed run called Side Order, just below the Green Chair, and was cut in 1999 for the run. The tree is relatively small, 120 centimetres across the stump, and the inner 20 centimetres is hollow. The sound wood contains 1,044 rings, and I estimate the total age at about 1,300 years.
We usually talk about ages in years, and there’s no doubt 1,300 years is old. But I find it even more staggering to think the tree started growing in A.D. 700. It puts a different spin on the concept of a Whistler local.
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A study like this one gives us a better idea of the Range of Natural Variation in our forests, that is, how our forests change over time. We know more about how much the proportion of old forests has decreased. We therefore know how much less habitat there is for wildlife species that require the big trees and logs found only in old forests. And we can use the variations in the natural forest as a template for improving wildlife habitat in second-growth stands.
Another application of this research is to help guide wildfire risk reduction. It is risky to work outside natural cycles, as shown by recent fires in B.C.’s Interior. Before fire suppression, fires in those dry forests were frequent and relatively mild. The Smokey-the-Bear approach to fire suppression allowed fuels to build up to the point where fires burned so hot they were uncontrollable.
In Whistler, recent changes to our forest have been caused by clearcut logging and urban development, not by fire suppression. Studies like this help managers predict which types of forests are most likely to burn and help guide strategies to reduce that risk. Ideally, any efforts to reduce the risk of fire will also ensure we do our best to protect or even improve wildlife habitat.
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I went up to Side Order a few weeks ago with Paul Duncan and his huge chainsaw. Paul cut three disks off the rotting stump of that 1,300-year-old yellow-cedar to make into displays. The disks are now at a specialty woodworker’s in Chilliwack for preparation, then they head to UBC for precise dating and labelling.
By the end of January, you will be able to see one of the disks at the museum, council chambers, or in the Roundhouse on Whistler-Blackcomb. Bring a good magnifying glass if you want to count the rings.
Bob Brett is an ecologist who used to call himself local before meeting a 1,300-year-old tree. He would like to acknowledge funding support from the Resort Municipality of Whistler and the assistance of Dr. Lori Daniels and the University of B.C. Tree Ring Lab.
