Trailing blackberry (Rubus ursinus) is a native shrub in the Pacific Northwest that is often confused for the invasive, Himalayan blackberry (Rubus discolor). It has also been known as Dewberry or Cascade blackberry, but Trailing blackberry is the most common name.
In general, Trailing blackberry is a slimmer, daintier plant that grows horizontally (like a trail) compared to the big, thorny Himalayan blackberry, which grows more vertically.