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The composition of the greenline plant community is linked to the stability of riparian ecosystems. Cool season exotic upland grasses are invading native plant communities across the northern Great Plains, potentially compromising streambank stability and increasing the risk of erosion within riparian ecosystems.� To determine how the species composition of the greenline community impacts stream type and the risk of streambank erosion, thirty five reaches across five watersheds were sampled to determine the dominant greenline vegetation. At each reach sampled, a cross-section was conducted to determine the stream type, greenline vegetation, and the risk of streambank erosion.� The stream types were delineated using Rosgen�s classification of natural rivers methods that separates reaches based on the parameters of entrenchment ratio, width to depth ratio, sinuosity, slope, and dominant channel materials (Rosgen 1994).� Canopy cover and composition was assessed using the line point intercept method along a 100 ft. transect in the greenline community.� The Bank Erosion Hazard Index (BEHI) was used to assess the streams risk of erosion by calculating the difference between the bank height and bank full height, average plant rooting depth and density, bank angle degree, and the dominant texture of the bank material.� A Nonmetric Multidimensional Scaling ordination was performed to analyze the data.� Analysis of the data determined that the most stable stream types (E and C channels) and lower BEHI scores were associated with high amounts of litter and facultative wet species.� In comparison, unstable F channels were associated with early successional species and bare ground.� �Sites with the higher BEHI scores were influenced by upland and facultative upland species and saline soils.� Late successional facultative wetland species therefore offer the most protection to intermittent stream banks.