This is the one I’m talking about.
http://bugguide.net/node/view/475348
Native Bees of North America
Native bees are an unappreciated treasure, with 4,000 species from tiny Perdita to large carpenter bees, they can be found anywhere in North America where flowers bloom.
Most people don’t realize that there were no HONEY BEES in America until the white settlers brought hives from Europe. These resourceful insects promptly managed to escape domestication, forming swarms and setting up housekeeping in hollow trees, other cavities or even exposed to the elements just as they had been doing in their native lands.
Native pollinators, in particular bees, had been doing all the pollination in this continent before the arrival of that import from the Old World. They continue to do a great deal of it, especially when it comes to native plants.