Here's a Somei-yoshino blossom for comparison. Our book says "sparcely hairy pedicels". These look quite hairy to me, but I still think they're the real deal. Here is Single White #1. I don't know if hairs would show up with the amount of zoom I had to use to get close to these pedicels. This was also posted in the P. serrulata var. Spontanea thread. I think that this is one about which Douglas said:I think these trees might be a selection of P. serrulata var. pubescens (Korean hill cherry). I was getting confused in that thread, so I'm checking that this is the one you meant, Douglas. Here is Single White #2, which everyone on the walk yesterday thought was Somei-yoshino, but I don't think its pedicels look the same as Somei-yoshino, and I wonder(ed) if it's the same as SW#1. Actually, I only wondered that until I posted them together. Now I think it looks like Pandora.
The hairs on pedicels will spread out and become more sparse as the temperature rises and pedicels elongate. The second line of images (I assume they're all of the same tree) looks a little like what I think may be P. serrulata var. spontanea. A closer look would be helpful. If the pedicels are glabrous (without hairs) and the leaves have only tiny marginal serrations and whitish undersides, that would be a reasonable diagnosis for Japanese hill cherry. On the other hand, if the pedicels and petioles are pubescent, the leaves more coarsely toothed and the undersides not whitish, then we can assume P. serrulata var. pubescens (Korean Hill). The third set of images look like 'Pandora' to me. If there are hairs on the pedicels, then we're probably looking at the Victoria Drive mystery tree.
Thanks for the reply, Douglas. Remember that ladder you were going to drag down to the park last year? I was using a 15x zoom to get those photos! We won't be getting a closer look unless we get a windstorm and a branch breaks off like it did for the Somei-yoshino whose blossom photo was the first one. Well, maybe I'll get lucky.