I found a small wild rose bush on Sunday. Only thing is that evening when I looked to Peterson's for an ID, I discovered that five rose species all looked quite similar and that my pictures couldn't help me. Monday I revisited this little plant, mindful of the identifying characteristics. I sat down next to my friend and spent some time simply looking before using the camera--by then, I already knew that this was indeed the Swamp Rose, Rosa palustris.
Swamp Rose has an affinity for water and this bush grows on a slope just feet from the lake's shore.
Compared with other wild roses, the Swamp Rose will often have more than three leaves to a twig and hook-like thorns. The presence of narrow stipules (sheath-like growths) just before the leaves finalize this id.