The ability of riparian buffers to exist as an effective conservation practice has been well documented especially in Central Iowa. The purpose of this study was to evaluate a five-year-old riparian buffer located in the Loess Hills region of Southwest Iowa. We hypothesize that the riparian buffer vegetation will increase soil water infiltration, soil moisture, and reduce soil erosion when compared to a no-till corn (Zea mays L.) and soybean (Glycine max L.) rotation system. Rainfall simulations were performed within 2.97m2 plots on a Kennebec (fine-silty, mixed, mesic Cumulic Hapludoll) soil. The vegetation comparisons included a no-till corn-soybean rotation, a riparian buffer of trees (cottonwoods, Populus deltoids Bartr. L.), cool season grass (smooth bromegrass, Bromus inermis L.), and warm season grass (switchgrass, Panicum virgatum L.). Rainfall simulations were replicated five times per vegetation. Significant differences (P<. 05) in the total infiltration after the establishment of steady state were observed between the four vegetations, between years, and when the year by vegetation interaction was taken into consideration. The total amount of sediment yielded during steady state between the four vegetations was reduced by 74%, 73%, and 72.6% by the cottonwoods, bromegrass, and switchgrass respectively when compared to that of the no-till corn-soybean rotation. Soil moisture was also found to be significantly different between the four vegetations with the cottonwoods consistently having greater antecedent soil moisture than the other riparian buffer vegetations and the no-till corn-soybean rotation system. These results indicate the ability of a riparian buffer to positively affect the soil water infiltration, soil erosion, and soil moisture in the erosion prone Loess Hills of Southwest Iowa.