Eastern sand cherry (prunus pumila) is a 2-6' tall, loosely-branched shrub that spreads by rhizomes and is well-adapted to dry, sandy sites like dunes, rocky slopes and dry meadows. It prefers full sun. The fruits of sand cherry are edible, but more highly prized by wildlife than by humans. The leaves can provide fodder for livestock and cover for wildlife in otherwise open habitats. Flowers appear in May-June and are followed in summer by reddish-purple fruits that mature to almost black. I saw a purple/red-leafed cultivar for sale, but I'd recommend the straight native plant since it hosts a whopping 381 species of lepidoptera (moth and butterfly caterpillars), none of which can eat the cultivar - anthocyanins give the cultivar its uncharacteristic red color, and they're feeding deterrents, so caterpillars cannot feed on the cultivar.