My daughter lives in Salem and we would like to plant a Strawberry Tree (dwarf Arbutus unedo). Can you verify the growing zone there? There are a couple of arbutus outside the Salem library that seem to have weathered well, but is it common for them to freeze in Salem winters?
Strawberry tree (Arbutus unedo) is fully hardy in the Willamette Valley. Salem is USDA Zone 8 and I've never seen one suffer winter injury. There's a really nice example, one of the best I've seen, on the south side of Bush House in Bush's Pasture Park in Salem.
The compact forms of the species are definitely worth seeking out as the species itself can grow to be 12' tall and up to 20' wide. It's huge. The compact forms include 'Elfin King', 'Compacta' and 'Oktoberfest'. Check with local nurseries to see what varieties they carry 'Compacta' will likely be most common. Also see the discussion of the plant in the OSU Landscape Plant website.