Live in Toronto. Have 2 sucker trees (as my wife calls them) growing between a fence and a deck. They flower with berries and create a huge mess on the deck and patio below and foul up the pump on the hottub. I would like to replace them and am looking for suggestions. The current trees provide some privacy and I would like to make sure the new ones also do.

Other requirements: the space between the deck and fence is only about a foot and the fence goes to about 6' in height. So I would need something fairly narrow that would grow ideally to only 10-14'. I do not want something with berries obviously. The soil is sandy and it get full afternoon sun. I could go evergreen (green giant?) or dwarf tree or something like a poplar (although I read the roots can be a problem). I do not really need the privacy in the winter as we dont spend a lot of time on the deck in -25

Any suggestions would be most helpful. Thanks