Lavender "pea flowers" loosely grouped towards the tip of a long climbing vine. The leaves of vetch are arranged in a long set of oppositely positioned oval leaflets.
Tidbits:
There are several varieties of vetch in the Pacific Northwest, but unfortunately the plant has a popularity problem with me. How do you get excited about a mostly non-native plant that has the name "vetch"? The American variation of the Common Vetch (American Vetch) produces cyanide when swallowed -- so keep the seeds away from kids.