Common Galls of Southern Ontario

I wanted to compile a list of some of the common galls one might encounter here in Guelph, Ontario. I have been spotting a few lately and wanted to build a little database for myself and for others who may encounter them and want to know a little more. The galls are named by the inducer, and what I mean by that is the insect as all galls below induced by insects. I hope to make a series of posts over time.