Saturday, May 30, 2009

Perils of urban tree identification.

I was walking down a street in Vancouver, on my way to a particular sporting goods store to purchase a particular (and expensive) pair of shoes. The store is a few blocks from a relative's home, which is where we parked the car.

On a particular block of the street, papery, brown flakes the size of cherry petals were drifting down, forming drifts next to curbs and speckling lawns, driveways and parked cars. These were seeds--samaras-- from whatever the trees were that lined this block.

The samaras were familiar, yet I couldn't place them. Something I had known long ago, but not quite. What were these trees, which I couldn't remember seeing anywhere else? Trees in Vancouver can be from almost anywhere on the planet.

The bark was coarse and shaggy. The leaves were oval, with serrated margins and prominent parallel veins--and with asymmetrical bases, one side convex, the other concave. Okay, that last trait means Ulmus, elm. I remember that from grade 2.

I went to the particular sporting goods store and bought the particular (and expensive) pair of shoes. Then I started back to the car, but pausing to take pictures of the trees, to help with identification.

There are about 18 species of elm, found throughout the temperate Northern Hemisphere. I had grown up in southern Ontario, among the rare survivors and common stumps of the American Elm, which had been decimated by beetle-borne Dutch elm disease. These trees were close, but not the right shape.

I remembered American elms as looking like heads of broccoli, like carnation flowers.

Many of the trees along this street were towering, and pyramid-shaped.

I met a man who was mowing his lawn amid the samara shower. I asked if he knew what kind of trees these were. He said No, and that they may be messy now, but were worse in the fall. "Three solid days of raking!"

My guess was these were some European elm species that for some reason had been planted along this block decades ago, and nowhere else. With this assumption, I was happily surprised to see licorice fern, a staple of BC coastal rainforests, growing from the north side of the trunks of some of the trees. These were well-integrated foreigners.

I got back to the car, and realized that I had left my box of particular (and expensive) shoes on the ground somewhere. I ran back to that block. The box was beneath the tree closest to the sporting goods store. I really must learn to pay more attention to things.

Back home, I referred to Trees of Vancouver, by Gerald B. Straley. This is an interesting book that catalogues the exotic and common trees of Vancouver. It gives precise addresses for many examples. I went to the elms and didn't bother keying them out by leaf and samara (which isn't always easy anyway). I looked at the lists of localities throughout the city, for one found on 23rd Ave between Laurel and Oak. The book says, about Smooth-Leaved Elm, Ulmus carpinifolia (native to Europe, North Africa and western Asia), 'Sarniensis' cultivar: "This is a very distinctive cultivar with a narrow pyramidal habit...and there are street plantings...along 23rd Avenue from Oak Street to Laurel Street."

So there it is. How could you live beneath these trees for years, cursing their fallen leaves, without bothering to find out what they were. As soon as I saw them, I had to find out what they were, particular shoes be damned.


Straley, G. B. 1992. Trees of Vancouver. UBC Press.


Karen said...

That's totally wacky and a really good story. Glad you found out, maybe next time you go to buy your particular/expensive shoes there, you can leave a note for the raking guy to tell him what he's got. Then again, he probably doesn't care, as you say, or he would have found out already. Hey, thanks for adding me to your blogroll, don't know if that's recent but I only just noticed. I am the opposite of you, a know-nothing, but maybe we share an tendency to try to notice our natural surroundings more than the average human. I even thought of you on the beach today when I was trying to show some random boy how to be more gentle to the tidepool creatures! I hope he listened.

Anonymous said...

i guess some people DGAF about trees.

Sally said...

Nice-- and I like that shape. Our favorite backyard shade tree here is a Chinese (or maybe Siberian) elm, invasive exotic species, but this one tree is a pleasure despite the occasional messiness.

Nice write-up, shoe distraction and all...

Wanderin' Weeta said...

We used to do that, when we lived in Vancouver; wander about, look at trees, and go home and look them up. And a woman swore at me when I mentioned that the fallen Japanese plum petals carpeting the street were beautiful.

Hugh said...

Karen, Thanks. Knowing the names or not, I think the wiring to notice lving things either is there or isn't. (Mostly isn't.) Good for you regarding boy and tidepool creatures, and thanks for thinking of me!

Anonymous, Yes.

Sally, I like the shape of the tree too. How could you live beside that tree and only know it as "tree?"

Weeta, Ah yes, those messy petals. If you don't have the book I cited, see if you can find it. You can do the reverse--find an intriguing tree in the book and track it down in the city.

Wanderin' Weeta said...

Yes, we have that book. I like your idea of looking up the tree first. Maybe we'll try it next time we're in town.

April Lorier said...

Just love the two street scenes you shot. Makes me want to live there, and I'm from one of the most beautiful spots in the world! Thanks for the story and the photos!