One handy but lesser known feature is the ability to selectively backup local folders.
For everyone that wants to upload somebut not alllocal pictures, though, it’s a welcome change.
To make use of the changes, enable Auto Backup in Google+, then head to the Photos app.
If it doesn’t, try updating Google+, or just waiting for it to roll out.
Update: It turns out this feature isn’t entirely new.
Google+ Now Lets You Pick Individual Local Folders For Auto Backup| Android Police