My decade old Arbor Day generic Acer palmatum is biting the dust. I figure it was weakened by last year's drought and succuming to something, probably verticillium wilt this year.

It was a vase shaped tree and this spring had lost three and six foot branches to the disease before losing one of its three trunks now.

I would love something similar to put in the area. Small, maybe medium tree. The vase shape contrasted with other trees I have. Berries and any "mess" are just fine.

The spot is:
damp
maybe 25 feet from the road
probably gets sun from 10 to 4 most days
soil is clay based and has a THICK topsoil layer as it is the bottom of my hill.

I already have Cornus florida, Cornus controversa, Nyssa sylvatica, Amelanchier lamarckii (serviceberry tree), and a Malus sp prairiefire crabapple.

What else do I need that I should plant there this fall?

Here is a link that might be useful: http://www.botanicalgarden.ubc.ca/forums/showthread.php?t=78693