It looks like bindweed or morning glory to me but can't tell for sure without seeing flowers. I did see holes in the leaves - does it have bugs on it that look like ladybugs but are shiny gold? They eat morning glories/bindweed and are really cool. The kids call them 24 karat ladybugs.
I never did see any insects nor flowers. I made the decision to go ahead and remove the vines and compost them as they were definitely choking my oats & peas.
I may never know exactly what it was, but that's ok.
Thanks for the help all, I agree it's most likely either bindweed or morning glory.