It could just be Rosa Multiflora, which is hardy to zone 4. I have one in my garden that looks just like that. It's a once bloomer and runs rampant in a dark and shady corner of the garden. One part of it is climbing up a black walnut tree.
http://www.helpmefind.com/rose...
Have you bought any roses from Canadian nurseries? They use it as the rootstock for grafted roses.
