Rhus glabra
From the USDA
Trivia tidbit: Rhus glabra is the only tree or shrub native to all 48 contiguous US states.
Smooth sumac is a native, perennial, deciduous, thicket-forming shrub or small tree that grows from 2 to 20 feet (0.5 to 6 m). Branches tend to be fairly sparse, smooth, and stout. The flowers are borne in long (up to 18 inches (45 cm)), dense, compound, terminal panicles. The fruit is a small drupe containing a single small seed. Smooth sumac has a high tannin content.
Smooth sumac thickets are often connected by branched rhizomes . The main roots grow to depths of 7 to 8 feet (2.1-2.4 m) and give rise to many smaller roots. The dense network of main roots, relatively shallow laterals, and rhizomes promotes increased utilization of soil moisture and rapid vegetative spread. Rhizomes reach to a depth of 3 to 12 inches (7.6-30.5 cm).