Here is a plant given to me by a friend at a botanical garden. Acer pseudosieboldianum, a.k.a. Korean Maple or Purplebloom Maple. It was labeled Acer tegmentosum-Manchu Maple. I went along with that for awhile but as I read and researched this and other maples I decided that it was Acer sieboldianum. I contacted the nursery that produced it and they said that they produce A. pseudosieboldianum but don't produce A. sieboldianum, therefore I am now sure that it is the species pseudosieboldianum.
Here is a pseudosieboldianum The difference with sieboldianum is a sticky white layer on young leaves. More infos here
Acer pseudosieboldianum - private collection (seed grown). Photographs: April 2002; May 2002; June; 2001; July 2002; August 2001; October 2002.
Acer pseudosieboldianum ssp. pseudosieboldianum - Washington Park Arboretum, Seattle, accession 1967.
Jacobson, NORTH AMERICAN LANDSCAPE TREES says "Leaves roundish, (7)9-11 lobed, to 5 1/2" wide, very downy, deeply lobed. Flowers purple. Young twigs lightly hairy. Fall color brilliant orange or red. By contrast, the leaves of its Japanese cousin, "the real" A. Sieboldianum, have 9 lobes almost exclusively, are less deeply lobed, less conspicuously toothed, and have earlier fall color; the flowers are later, and yellowish-white rather than purple."
The British champion Acer psuedosieboldianum at Westonbirt Arboretum. Measured at 8m tall in 2008. Fall colour October 2010:
