The Niobrara River valley is home to unusually diverse plant groups and ecosystems. The area is noted in scientific literature for the many plants that exist here beyond their normal geographic limits. Plants of eastern, western, and northern forest ecosystems and three Great Plains prairie ecosystems converge here. Approximately 160 plant species are at the edge of their natural range in the river valley.
Several factors cause Niobrara's habitat "neighborhoods" to have unusual biological diversity. The river valley provides an unbroken east-west riparian corridor connecting the drier western landscape with the more humid midwestern prairie and eastern forest. Plants typical of each condition intermingle in this transition zone.
The river valley diveristy of habitats is also due to differing slope, moisture, and soil conditions. As climate conditions change over time, plants typical of past colder conditions continue to survive in the sheltered cool, wet, north-facing branch canyons while they have disappeared from drier, warmer, more open areas.
For more information on native plants of Nebraska and their distribution, follow the links below.
Native vegetation map - Univ of Nebraska State Museum
Index of native plant species - University of Nebraska State Museum