Forested stream banks, compared to grassed ones, can destabilize stream channels by promoting erosion. Four reaches of Coon Creek, Wisconsin, each with long-term grassed and forested subreaches were examined. Grassed reaches were narrower and had smaller channels (bankfull cross sections) than forested reaches, suggesting that grassed channel reaches stored about 2100 to 8800 m3 more sediment per kilometre than forested reaches. Available evidence suggests that conversion of riparian forests to grass would allow storage of sediment along channels, possibly decreasing downstream sediment yields. These findings are important as many grassed riparian corridors are rapidly reverting to forest because of economic conditions and governmental policies.