Looks like some star flower (Lysimachia borealis) leaves in the center as well.
Thanks, abgardeneer and fatamorgana.
abgardeneer got it right. The leaves of Lysimachia are quite different from the ones in the picture which are clover shaped.
One of the plants on the lower left looks like a bunchberry, cornus canadensis.
That is right, moleman83. The dogwood, sorrel and the twinflower all seem to grow together on woodland floors of Cabot Trail.
I agree with FataMorgana regarding the starflower in the middle of the image.
Yes, Fatamorgana was adding further (correct) info about other plants in the picture, not the Oxalis.