Bridging the conservation lands – working lands divide with a cost-effective strategy to enhance ecosystem services
With much of the U.S. Midwest in agricultural production and under private ownership, any viable conservation practice must fit within the context of currently profitable production systems. We study the ability of strategically integrated “prairie strips”—contour buffer and filter strips composed of diverse, native, perennial plants—to achieve this. We hypothesize that the conversion of small amounts of row-cropped watersheds to native prairie can provide environmental quality and conservation benefits that are disproportionately greater than expected based on the land area converted. We have been testing this hypothesis since 2007 at the Strategic Trials of Row crops Integrated with Prairies (STRIPs) research and demonstration site, a replicated watershed experiment at Neal Smith National Wildlife Refuge in central Iowa, USA.
Thus far, we have found that prairie strips comprising 10-20% of no-till corn-bean agricultural catchments reduce sediment transport by 95%, total phosphorus and nitrogen transport by 90%, and surface water flow by 60% compared to catchments entirely in no-till corn-bean agriculture. These results are consistent across a range of weather conditions, including high-rainfall and drought years. Prairie strips also provide habitat for native plants, insect pollinators and natural enemies, and birds, including some species of greatest conservation need. Financial analysis of the practice reveals that depending upon total area covered by strips relative to the whole field, the annualized present value costs of using prairie strips can be as little as $59 to $87 per treated ha/yr. If prairie strips were under a 15-year Conservation Reserve Program contract, total annual cost to farmers would be reduced by over 85%, and affordable compared to other common conservation practices, such as terraces and wetlands. We also share insights from implementing prairie strips on privately owned farms. In sum, prairie strips offer a way to efficiently meet multiple conservation goals through easy and flexible incorporation into existing farming systems; hence, an effective means of bridging the conservation lands - working lands divide.