A bioeconomic analysis of an emerald ash borer invasion of an urban forest with multiple jurisdictions

摘要

Bio-invasions occur in management mosaics where local controlaffects spread and damage across political boundaries. We addresstwo obstacles to local implementation of optimal regional controlof a bio-invasion that damages public and private resources acrossjurisdictions: lack of local funds to protect the public resource andlack of access to protect the private resource. To evaluate theseobstacles, we develop a spatial-dynamic model of the optimal con-trol of emerald ash borer (EAB) in the Twin Cities metropolitanarea of Minnesota, USA. We focus on managing valuable host treeswith preventative insecticide treatment or pre-emptive removal toslow EAB spread. The model includes spatial variation in the owner-ship and benefits of host trees, the costs of management, and thebudgets of municipal jurisdictions. We develop and evaluate cen-tralized strategies for 17 jurisdictions surrounding the infestation.The central planner determines the quantities of trees in publicownership to treat and remove over time, to maximize benefits ofsurviving trees net costs of management across public and private ownerships, subject to constraints on municipal budgets, manage-ment activities, and access to private trees. The results suggest thatcentralizing the budget across jurisdictions rather than increasingany one municipal budget does more to increase total net bene-fits. Strategies with insecticide treatment are superior to ones withpre-emptive removal because they reduce the quantity of suscep-tible trees at lower cost and protect the benefits of healthy trees.Increasing the accessibility of private trees to public managementsubstantially slows EAB spread and improves total net benefit