A Multicriteria Framework for Producing Local, Regional, and National Insect and Disease Risk Maps

Ensuring the health of America’s forests requires the analysis, understanding, and management of complex and interrelated natural resources. Increasing human-use pressures, a continual threat from native and exotic insects and diseases (USDA 2005), and more complex management policies make natural resource management demanding. In order to accurately assess where and how forest resources are being impacted, resource managers and policy makers require information beyond tabular summaries. In turn, this requirement has created an increasing need for spatial-based, decision-support systems that can quickly summarize a wide range of tabular and geographic information. Such systems provide resource managers with the information they need to make clear, informed choices and efficiently allocate human and financial resources. Therefore, integrated and comprehensive approaches that use technologies, such as Geographic Information Systems (GIS), with their ability to analyze a large number of spatial variables concurrently, are becoming increasingly important for the protection and management of our nation’s forest resources (Ciesla 2000, McRoberts and others 2006, Mowrer 1992, Reynolds 1999, Stein and others 2005).

The primary goal in the development of the 2006 National Insect and Disease Risk Map (NIDRM) is the creation of a national communications tool that will provide policy makers, USDA officials, and Federal and State land managers with a periodic, strategic assessment for risk of tree mortality due to major insects and diseases. NIDRM is an integration of 186 individual risk models constructed within a common, consistent, GIS-based, multicriteria framework that accommodates regional variations in current and future forest health conditions, knowledge, and data availability. The 2006 NIDRM was created through a modeling process that is repeatable and transparent, and through which interactive spatial and temporal risk assessments can be conducted at various scales to aid in the allocation of resources for forest health management. This process is intended to increase the utilization of forest health risk maps within and outside the National Forest System.

The production of the 2006 risk map has been a highly collaborative process, coordinated by the USDA Forest Service, State and Private Forestry Area, Forest Health Monitoring Program (FHM). Entomologists and pathologists from all States and every FHM region were invited to take part in the process of developing the NIDRM. Teams were created with forest health and GIS specialists from the Forest Service, State agencies, and academia to oversee and assist in model development. Even though the goal of the authors is to describe in this paper the GIS framework developed for the construction of NIDRM and to briefly demonstrate how this process can be used to conduct assessments at multiple spatial scales, the authors want to emphasize the importance of a team approach that ensures participation from local resource managers.