Is Oregon's land use planning program conserving forest and farm land? A review of the evidence

Planners have long been interested in understanding ways in which land use planning approaches play out on the ground and planning scholars have approached the task of evaluating such effects using a variety of methods. Oregon, in particular, has been the focus of numerous studies owing to its early-adopted and widely recognized statewide approach to farm and forest land protection and recent experiment with relaxation of that approach in 2004 with the passage of ballot Measure 37. In this paper we review research-based evidence regarding the forest and farm land conservation effects of Oregon land use planning. We document the evolution of methods used in evaluating state land use planning program performance, including trend analysis, indicator analysis, empirical models, and analysis of indirect effects on the economic viability of forestry and farming. We also draw on data documenting Measure 37 claims to consider the degree to which Measure 37 might have altered land use and development trends had its impacts not been tempered by a subsequent ballot measure – Measure 49. Finally, we provide a synthesis of the current state of knowledge and suggest opportunities for future research. Common to nearly all of the studies we reviewed was an acknowledgement of the difficulty in establishing causal relationships between land use planning and land use change given the many exogenous and endogenous factors involved. Despite these difficulties, we conclude that sufficient evidence does exist to suggest that Oregon's land use planning program is contributing a measurable degree of protection to forest and farm land in the state.