Looks like it could be a hornbeam (Carpinus). Watch how those fruits develop to know for sure and get a full ID.
The leaves aren't all that convincing for hornbeam, unless some species I haven't seen. All those short spurs seem remarkable. Joseph, can your friend get a picture of the tree shape and the bark? I have questions about this myself. I can see why this was described as having opposite leaves, because there are so many leaves opposite each other in the photo. Yet the branching is not opposite. Does this really have opposite leaves? If so, that would rule out Betulaceae, but I'm not convinced they're really opposite. The narrow seeds look more like Betula, but I'm only seeing a few photos of genera with similar leaves, and when I check others of the same name, the leaves don't look similar.
Here is the picture of its bark. The tree is located at 126 Dunsmuir Street. He will take more photos tomorrow.
OK, that's a birch. I still don't see any leaves that match yours though. Maybe I have the wrong idea of the leaf size. Could you measure the leaves? Here is Betula nigra, River Birch, has a similar leaf arrangement and narrow seeds: http://newfs.s3.amazonaws.com/taxon-images-1000s1000/Betulaceae/betula-nigra-le-rsnellgrove-b.jpg
Yes, those leaves look right. Thanks, Michael. The original photos were very clear but misleading. The cones are only 3.5 to 4cm long, about 5mm wide; leaves are 7 to 9cm long. Thanks for including the address, Joseph. I walked past there today on my way to the Main St farmer's market - here are a few photos. These are privately-planted trees lining a parking lot, so are not on the city's list. I don't know what that boat thing is about.
