Site Concept Narrative: The Clayey Overflow Ecological Site

Site concept narrative:
The Clayey Overflow Ecological Site occurs throughout the MLRA. It is located on Stream Orders 2 or greater. This site is a run-in site and receive additional moisture through runoff from adjacent sites and overflow during occasional flooding. Typical slope range is from 0 to 2 percent. The soil surface layer is 5 to 11 inches in depth with a texture range of silty clay loam to clay. The natural vegetation will gradually shift from almost exclusively herbaceous species in the upper reaches of a drainage to a mix of species including; grasses, forbs, shrubs and tree, in the lower reaches. Vegetation in reference consists of a mix of cool and warm-season tall and mid grasses. Western wheatgrass, green needlegrass are dominant, big bluestem and switchgrass are sub-dominant. Forbs are common and very diverse. Patches of western snowberry, American plum, chokecherry and willow are almost always present. Major tree species include: plains cottonwood, willow, green ash, boxelder and
Changes will occur in the plant communities due to short-term weather variations, impacts of native and/or exotic plant and animal species, and management actions. While the following plant community descriptions describe more typical transitions between communities that will occur, severe disturbances, such as periods of well below average precipitation, can cause significant shifts in plant communities and/or species composition. As this site deteriorates, species such as blue grama will increase, and introduced species such as Kentucky bluegrass, smooth brome and Canada thistle will invade the site. Grasses such as slender wheatgrass, green needlegrass, big bluestem, rhizomatous wheatgrasses, prairie cordgrass, and switchgrass will