Rubus pensilvanicus (Pennsylvania Blackberry or Wild Blackberry), is a thorny bramble native to eastern North America.
The canes are green at first but then turning dark red, usually ridged, with copious straight spines. The leaves are compound, usually bearing 5 or 7 leaflets. The flowers are white with large petals, bourne in mid-spring. The fruits are large aggregates of black drupelets, thich are somewhat sweet and often used for jams and jellies.
While rarely planted, the wild blackberry does provide showy flowers and fruits, and is attractive to songbirds and other wildlife. Like all Rubus species, it can serve as a host to diseases that can affect the cultivated types.