Published online by Cambridge University Press: 21 July 2017
Paleosols Crop Out extensively in the Appalachian region of eastern North America, from the Canadian Maritime Provinces southward to the Tennessee-Alabama border along the western side of the Appalachian Orogen (Fig. 1). The paleosols occur primarily in terrigenous clastic redbed deposits ranging in age from Late Ordovician to Early Permian (Mora and Driese, 1999; Driese and Mora, in press), which encompass a time interval characterized by rapid evolution and diversification of terrestrial ecosystems (Table 1). These Appalachian paleosols formed under relatively constant sediment-source area and pedogenic environments (Table 1); thus they share generally uniform physical and chemical properties. As such, they are suitable particularly for investigating evolutionary advances in the gross morphology of plant roots and rhizomes, preserved as traces, and their relationship to physical and chemical features in the paleosols (Table 2). Important changes in plant abundance, rhizome and root systems, and adaptive capabilities are recorded in the paleosols, concurrent with a proxy record of changing environmental conditions. Paleosols represent a still-underutilized record of the terrestrial ecosystem (Retallack, 1990).