I am afraid I cannot identify this plant based on these pictures. The best recourse would be to dig up one plant, roots and all, and take it to your local extension office at 996 Jefferson in Eugene (10th and Jafferson, entrance on 10th). Most identifications are on mature plants in flower, but often if it is very common these pictures might suffice. By the way, under the middle plant appears Shining Geranium, a stubborn invasive ground cover. In person, elements such a root type, possible hairs, underleaf color growth habit from the ground up all may lead to a good ID. If it flowers, then the ID becomes much better.