Blue River Sand Barrens features one of the largest and best examples of this harsh and arid ecological community in Wisconsin. Sand barrens are upland communities that develop on unstable alluvial sands along rivers such as the Mississippi and Wisconsin. They are partly or perhaps wholly anthropogenic in origin, occurring on sites historically disturbed by plowing or grazing. The flat, sandy areas resemble dry prairies but contain actively moving sand dunes, and dunes stabilized by a thin forest cover of black and Hill's oak. "Blowouts", large, unvegetated depressions in the sand surface and eroded by wind, are scattered throughout. Early dune and blowout colonizers include false heather, bearberry, and sedges while species such as three-awn grass, June grass, rough blazing-star, hoary puccoon, sand cress, and prickly pear cactus are common in the barrens. Sizeable populations of two rare species, prairie fame-flower (Talinum rugospermum), and poppy mallow (Callirhoe triangulata) are found here. Invertebrate life includes unusual species and an abundance of ant lions. Reptiles are a very prevalent component of the barrens fauna and include six-lined racerunner, hognose snake, and blue racer. Many turtles use the sandy dunes for nesting. Additional animal life includes vesper sparrow, Franklin's ground squirrel, and numerous nocturnal rodents. Blue River Sand Barrens is owned by the DNR and was designated a State Natural Area in 1968.