I've got this vine which has starting getting out of hand in my yard. Last
year I saw a few stray strands of it growing among the Vinca but this
spring
it seems to have taken off and looks like it might overtake and smother
the
English Ivy in the woods! A picture and description appears at
http://johnmcgaw.com/mystery%20vine.html

I have it growing along fence lines and trees here as well. It's not poison
ivy. Offhand I'd say Wintercreeper Euonymous Fortunei. It's actually
pretty invasive.

James