Cow vetch pops up in gardens, but is it a friend or foe?

Cow vetch. Vicia cracca or tufted and bird, blue or boreal vetch, is a species of vetch native to europe and asia.

Vicia cracca (tufted, cow, bird, blue or boreal vetch), is a species of vetch native to Europe and Asia. It grows in meadows, slopes, in shrubs, on forest edges, less often in light forests.