Gerald Straley, in Trees of Vancouver, says that there are a number of specimens of Platanus orientalis "planted with the hybrid London Plane Tree (Platanus x acerifolia), although they may be merely hybrid seedlings that tend more toward that parent". They're supposed to be at Ceperley playground in Stanley Park, which is where these trees are. The orientalis leaves are supposed to be more deeply lobed, but the ones that look more deeply lobed to me have the extra leaf notches that match the drawing of the acerifolia. The one with the least peeling bark has the leaf that matches the acerifolia, which is supposed to have more peeling bark than P. occidentalis. The oriental plane's fruits are supposed to be smaller, but the tree with a lot of small fruits also had some large ones. I just want to know if I found the orientalis, and if so, which one was it? Tree 1 Tree 2 Tree 3 Tree 4
Probably "they may be merely hybrid seedlings that tend more toward that parent" covers it. The same kind of thing has been observed down here. "In Seattle, uncommon; almost solely represented by old trees on public property. Such trees may be backcross London plane hybrids that have inherited nearly all of their superficial characteristics from the oriental rather than the occidental species. It is also possible that Seattle's are genuine Orientals. It is neither easy to determine nor particularly pressing to do so. The trees thrive and are attractive here - their technical identity is curious but of secondary importance compared to this happy fact. To distinguish them from our London planes: the Oriental's seed-balls frequently number 3 per string and are smaller, their leaves are deeply lobed like those of our native Bigleaf Maple" --A.L. Jacobson, Trees of Seattle - Second Edition (2006)
So you're saying that even though I think the leaves on tree 1 and tree 3 look entirely different, that's not enough to identify them as different trees, is that right? I went on a guided tree walk tonight and learned that the small round flowers are male and the large ones female.
They all look like London Planes to me too. The large and small clusters on yours are respectively left-over seedheads from last year, and this year's flowerheads; the latter will grow to be the same size as the former later in the year. Oriental Plane has more deeply cut leaves, and 3-6 seedheads per stem. Here's foliage of one at RBG Edinburgh.
Thank you so much, Michael, for straightening me out on the seedheads, and the photo. That looks quite different to me than the drawing, so I had a different idea of what more deeply cut looked like. I was with a friend last year who thought Liquidambars were P. orientalis, and I wondered how I'd tell the difference. It helps that we probably don't have any young P. orientalis!
This isn't orientalis either. It's labelled as Platanus occidentalis, American Sycamore, on the Trees of Reed (College, in Portland, OR) campus map22. I was struck by the size of the leaves - the one pictured easily extended beyond the edges of the 11.5"x9.5" folder - and also the huge, over 2" in diameter (are they?) stipules (see the upper left corner of the second photo). The bark on the trunk is finely checkered and not peeling, but the last photo shows it peeling off one of the branches.
The non-shedding bark may be connected with the climate too, perhaps an effect of slow growth - I've seen it frequently on London Planes in NE England, where summers are far cooler than they like.
