Date of this Version
The Niobrara Valley Preserve is a 219 km2 area along the Niobrara River in north-central Nebraska. Five hundred eighty-one species of vascular plants, about one-third of the total known from Nebraska, are recorded from the Preserve. They are distributed among 332 genera in 105 families. The floristic richness of this area may be attributed to two major factors: 1) a unique surface and subsurface geology has produced hydrologic and pedologic conditions amenable to a variety of plant communities; 2) Pleistocene and post-Pleistocene climates were critical in determining the co-occurrence of diverse vegetation types in the Niobrara River Valley. Among the principal plant communities juxtaposed in this area are three grassland types (sandhills, mixed, and tallgrass prairies) and three forest types (ponderosa pine, paper-birch, and eastern deciduous).