I really should get to know my neighbours better. I mean, they're out there every day, waving their arms and producing oxygen, and all I say in return is, "Hi, tree!" I don't even know their names.
City arborist Kevin Veenstra and the crew at public works make it their business to know these neighbourhood trees, having plotted the location of each on a huge map as part of a recent update to the city's tree inventory. Covered with As, Ms, Bs, Cs, and Ls of all different colours, this wall-sized chart tracks the type and location of each public tree in St. Albert.
St. Albert has about 558,800 trees on public lands, reports the 2011 tree inventory, with precisely 51,327 along our streets and 13,532 in the parks. Crews haven't counted them specifically, but believe there are 17,029 trees in the buffer areas and 476,909 in natural areas.
A quick look at the map reveals a few obvious trends. First, there's about a zillion green As on it. These are ash trees, Veenstra says. With some 25,000 of them in town, they're the city's most common boulevard and park tree.
Second, older neighbourhoods such as Grandin tend to have streets dominated by a single letter – all As for ash or Ms for Manitoba maple. If a pest strikes one of these species (e.g. emerald ash borer in ash), whole streets will become treeless.
"The new style is to alternate trees," Veenstra says, so that one species can be removed without wiping out a region's tree cover. That's why the tree map for new places such as Heritage Lakes looks more like alphabet soup.
Meet your tree
Most of St. Albert's ash trees are either mountain or green ash, says Peter Murphy, a retired forestry professor in St. Albert.
"The distinguishing thing about an ash tree is that it has a compound leaf," he notes – each stem off a branch has many leaves instead of one.
They're also "depressing," Veenstra says, as they're the last to get their leaves each year and the first to lose them. But that's also the source of their hardiness – by leafing late and shedding early, these trees dodge the sudden dumps of wet, heavy snow that Alberta gets in early spring and late fall.
"The elm trees, a late snowstorm just devastates them," he says.
Mountain ash trees will grow huge baskets of red berries each summer that bohemian waxwings devour in the winter. Green ash trees don't have berries, and have wider, less oval-shaped leaves than the mountain.
Elms are the second most common boulevard tree in town, with some 4,170 in the city's inventory.
American elms have a distinct vase or umbrella-like shape that forms a cathedral-like canopy over many local streets, Veenstra says – see Forest Drive for an example. If you look at their serrated leaves, you'll notice that one side is bigger than the other.
Elms make good boulevard trees because they're drought-tolerant and stay out of traffic due to their shape, Veenstra says. There also aren't many pests that bother them.
Murphy says elms are his favourite tree due to their wide canopy and general tree-ness.
"It's really heartening to me to see a boulevard of elm trees," he says. "It has that widespread, welcoming feeling."
Maples come in at number three on the city's list, with about 4,080 on city property. About 93 per cent of these are Manitoba maples, many of which are in Grandin.
Manitoba maples have compound leaves and rough bark, Murphy says.
"They're prolific seeders," he notes, and produce zillions of propeller-shaped seeds each year that can conquer whole regions. "In most municipalities now, they're considered a weed species."
Manitoba maples tend to attract aphids that squirt honeydew on everything, Veenstra says. These maples also have a short lifespan and a square, wide branch structure that interferes with traffic.
"The seeds are everyone's bane."
The city is replacing them with autumn blaze maples, Veenstra says. The blaze maples have white bark and patriotic leaves that, come fall, resemble the big red leaf on our national flag.
Blacklisted
Another tree on the city's blacklist is the hybrid poplar. With rough grey bark and heart-shaped leaves, these are the trees that produce the clouds of white fluff that blanket the city every summer.
Hybrid poplars were popular back in the 1960s because they grew fast and made instant canopies, Murphy says. Nowadays, the city wants to get rid of them – their roots crack pavement and their weak branches fall on cars.
There are at least 5,200 spruce trees in St. Albert, the city's inventory suggests – probably thousands more, as crews have yet to do a species-by-species breakdown of natural areas such as the Grey Nuns White Spruce Park.
Spruce trees are pyramid-shaped and covered in pointy green needles that are evenly spaced along branches, Murphy says. Compare this with pine trees, where the needles come out in bundles.
"The most predominant spruce here is the white spruce," Murphy says. This native species can be found across Canada, and is known for its dark green needles and general hugeness.
The Colorado blue spruce looks a lot like the white, Murphy says, except more blue in the needles.
"If you find a spruce growing in the swamp, it's probably a black spruce."
You'll find about 1,620 pine trees on city property, the tree inventory suggests.
Most of these will be lodgepole or jack pine, Murphy says, which frequently hybridize and are vulnerable to mountain pine beetle.
These trees have hard, spiky cones that are sealed with resins that don't melt unless exposed to heat such as that produced by a forest fire. Seeds in these cones can be protected for up to 30 years.
Often mistaken for a pine is the larch or tamarack, of which the city has about 200.
"These are the ones that turn yellow in the fall and shed their needles," Murphy says, and they are often found along the Sturgeon River. Expect to find soft green needles that grow in bunches of 15 to 30.
Trees are just as much residents of St. Albert as we are, Veenstra says. We interact with them year-round, enjoying their shade, raking their leaves, and cursing their branches when they crush our cars.
"It's there as long as you are there," he says. "There's a sort of intimacy there."
And they can bring us closer to our human neighbours, he says.
"It connects you with your neighbours who all share a common canopy."
