The genus Rubus contains many familiar wild edible fruit that grow on upright, arching canes (e.g., Common Blackberry, Red Raspberry, and Black Raspberry), as well as species who creep or trail along the ground, like Northern Blackberry (R. flagellaris, pictured here), who is also known as Northern Dewberry or Common Dewberry.
Northern Blackberry stays close to the ground and has divided leaves (each with 3 or 5 leaflets), and more than once I've been with people who've mistaken non-fruiting patches of Northern Blackberry for poison-ivy (Toxicodendron sp.) or wild strawberry (Fragaria sp.). Looking closely, you'll notice spines along the stem of Northern Blackberry, a feature these other plants do not have.
A patch of well-armed Common Blackberry canes will typically yield a larger quantity of fruit than a patch of Northern Blackberry, but N. Blackberry is still worthy of a forager's time. Savor a handful of the delicate, juicy fruit and you'll see what I mean. The plant's low stature allows many non-humans -- including mice and chipmunks -- to easily reach and enjoy the fruit, too.