This article explores the spectacular calcretes of south-central Washington. The thick, bright white CaCO3-rich paleosols overprint the Pliocene Ringold Fm, Plio-Pleistocene fanglomerates, pre-Wisconsin flood gravels, and early Palouse loess. The blanket-like hardpans formed in alluvial sediments low in the landscape where strong evapotranspiration moved large volumes of water through the soil column via vegetation rooted near the water table. The aridity necessary to precipi