The listing in PlantFiles for Betula apoiensis now has a link, "View this plant in a garden". Clicking the link takes you to some photos in Garden Showcase of an entirely different species of birch: http://davesgarden.com/showcase/search.php?plantname=Birch, Betula apoiensis
I doubt very much that the owner of the photos is making any claim that the tree-form birches shown in his/her photos are actually a dwarf species, Betula apoiensis, yet this is the link that comes up.
For PlantFiles to be useful, it has to contain correct plant info. Could you please correct this erroneous link?