Kentucky bluegrass, a nonnative species, has invaded rangelands in the United States and is currently present in most rangelands across the Northern Great Plains. Despite its accelerated expansion, the consequences of Kentucky bluegrass on the diversity of native plant species and on ecosystem services remain largely unknown. We synthesized the available data related to Kentucky bluegrass and how it affects native plant diversity and ecosystem services. We found that invasion may bring negative consequences to ecosystem services, such as pollination, habitat for wildlife species, and alteration of nutrient and hydrologic cycles, among others. To maintain the flow of ecosystem goods and services from these rangeland ecosystems, range science must adapt to the challenge of introduced, cool-season grass dominance in mixed-grass prairie. Based on our findings, we identify research needs that address ecosystem changes brought on by Kentucky bluegrass invasion and the corresponding effects these changes have on ecosystem services. We are dealing with novel ecosystems, and until we have better answers, adaptive management strategies that use the best available information need to be developed to adapt to the invasion of this pervasive invasive species.

Ecosystem-services scholarship has largely focused on monetary valuation and the material contributions of ecosystems to human well-being. Increasingly, research is calling for a deeper understanding of how less tangible, nonmaterial values shape management and stakeholder decisions. We propose a framework that characterizes a suite of sociocultural phenomena rooted in key social science disciplines that are currently underrepresented in the ecosystem-services literature. The results from three example studies are presented to demonstrate how the tenets of this conceptual model can be applied in practice. We consider the findings from these studies in light of three priorities for future research: (1) complexities in individual and social functioning, (2) the salience and specificity of the perceived benefits of nature, and (3) distinctions among value concepts. We also pose a series of questions to stimulate reflection on how ecosystem-services research can adopt more pluralistic viewpoints that accommodate different forms of knowledge and its acquisition.