No Such Thing as a Free Lunch: Trade-offs of Trees in Grassy Ecosystems

This case study explores environmental decision making in a complex socio-environmental system, the Great Plains grassland biome. We use an interrupted case method, where students explore how over the course of a century a native tree, Eastern redcedar, has transitioned from rare to invasive. In part 1, students are presented with the motivations that led to a biome-wide afforestation program and the first consequence that emerged. In part 2, students are presented with more complexity as Eastern redcedar becomes biologically invasive leading to the loss of native grasslands and a suite of socio-environmental tradeoffs. Students use concept maps, stakeholder analysis, and ecosystem service assessments to help understand and navigate the socio-environmental dimensions of the cedar issue. This case study emphasizes grasslands and cedar woodlands as alternative stable states supported by different stabilizing feedbacks that are strongly influenced by stakeholders and the environmental decisions that are made. This two-part case can be used for a wide range of courses in a few class periods (total class time approximately 4-5 hrs.)