Though their work seems vastly different in medium, nature serves as inspiration for both artists featured in the May exhibit at River Gallery, 400 E. Second St. "Materials Intertwined" reflects how Kim Keats of South Carolina entwines tree bark with stone and brick to make sculpture, such as "Root Relic Reliquary," and Bernie Rowell of North Carolina incorporates fiber, paints, collage and found materials into her art quilts, such as "Seasons Diptych." The opening reception will be held from 6:30 to 8 p.m. Friday, May 2, with both artists present. Keats will offer a demonstration of her sculpture, using bark and twigs from highland trees, along with driftwood and palmetto root from coastal habitats, from 11 a.m. to 4 p.m. Saturday, May 3. The exhibit continues through Saturday, May 31. Gallery hours are 10 a.m.-5 p.m. Monday-Saturday, 1-5 p.m. Sundays and by appointment. For more information, call 423-265-5033, ext. 5, or visit www.river-gallery.com.