Forest Health Indicators

"Forest Inventory and Analysis. The Forest Service Forest Inventory and Analysis (FIA) Program is the Nations continuous forest census. Since 1930, we have collected, analyzed, and reported information on the status and trends of Americas forests: how much forest exists, where it exists, who owns it, and how it is changing growing, dying, or being harvested. In response to widening customer interests, the FIA Program is developing a core program that will be implemented in the same manner on all U.S. forest lands. It includes sampling an extended suite of forest health indicators. The purpose of this brochure is to describe these health indicators: what we are measuring, why we believe these measurements are important, how we collect and interpret the data, and examples of what we have found to date. The FIA indicators discussed in this brochure are: crown condition, ozone injury, tree damage, tree mortality, lichen communities, down woody debris, vegetation diversity and structure, soil condition.

The Forest Health Monitoring Program's annual national reports present results from forest health data analyses focusing on a national perspective. The Criteria and Indicators for the Conservation and Sustainable Management of Temperate and Boreal Forests are used as a reporting framework. This report has five main sections. The first contains introductory material. The next three sections, S2Landscape Structure, S3 S2Abiotic and Biotic Factors, S3 and S2Forest Conditions, S3 contain results of data analyses. Some of the indicators discussed use data collected from ground plots. These include ozone bioindicator plants; changes in trees (crown condition, mortality, and stand age); and soils (forest floor depth). Other indicators or indicator groups use data about insects and diseases, and remotely sensed or ground-based data about distance to roads, forest edge, interior forest, drought, fire, and air pollution (sulfates, nitrates, and ozone). Identifying patterns and observing possible relationships is an important part of national level analysis and reporting. The fifth section S2Integrated Look at Forest Health IndicatorsS3 presents results of analyses designed to evaluate whether or not individual indicators or linear combinations of indicators discriminate between crowns in poor condition and crowns not in poor condition.

"The Forest Health Monitoring (FHM) Program's annual national report uses FHM data, as well as data from a variety of other programs, to provide an overview of forest health based on the criteria and indicators of sustainable forestry framework of the Santiago Declaration. It presents information about the status of and trends in various forest health indicators nationwide and uses statistically valid analysis methods applicable to large-scale ecological assessments. Five main sections correspond to the Santiago criteria: Biological Diversity, Productive Capacity, Health and Vitality, Conservation of Soil, and Carbon Cycling. A variety of indicators contribute information about the status of each forest ecosystem considered. Many indicators use data collected from ground plots. Such indicators include species diversity (tree and lichens), bioindicator species (lichens and vascular plants sensitive to ozone), changes in trees (crown condition, damage, and mortality), physical and chemical soil characteristics, and aboveground and belowground carbon pools. Additional information about forest health status and change is derived from data that are used to measure forest extent; data about insects and pathogens; and remotely sensed and/or ground-based data about forest fragmentation, fire, and air pollution. A sixth section presents and discusses a multivariate analysis of the indicators. The technique provides a composite picture of forest health, based on statistically significant principal components."--P. ii.

This report focuses on the Forest Health Monitoring Programs development and use of analytical procedures for monitoring changes in forest health and for expressing the corresponding statistical confidences. The programs assessments of long-term status, changes, and trends in forest ecosystem health use the Santiago Declaration: S2Criteria and Indicators for the Conservation and Sustainable Forest Management of Temporate and Boreal ForestsS3 (Montreal Process) as a reporting framework. Procedures used in five aspects of data analysis are presented. The analytical procedures used are based on mixed estimation procedures. Examples using the indicators are included, along with a clear link to the analytical procedures used (1) estimating change over time within groupsestimation of growth, harvest, mortality, and crown condition; (2) testing for differences in change over time among groupsfoliar transparency; (3) estimating change using covariatesimpact of drought on change in foliar transparency; (4) estimating plot values for unmeasured yearscomparison of observed and predicted (Best Linear Unbiased Predictions) values of foliar transparency, dieback, and total volume; and (5) estimating tree heightsexamples of using estimated tree heights to estimate tree volume.

This is the first in a series of papers intended as guides to the current and future directions of the Canadian Forest Service science program. It defines "forest health" and describes why the Service, in co-operation with a wide range of partners, addresses forest health issues through research, monitoring, and assessment activities in its science and technology research networks. Research areas are outlined in the fields of exotic insects and diseases, global environmental change, biological diversity, and forest management. Finally, some emerging issues in forest health are listed.