Fall 1991

Forest Health Monitoring

Neil Berg
USDA-Forest Service, PSW Research Station, Berkeley

(Adapted largely from a briefing paper by Joseph Barnard, National Program Manager, Southeastern Forest Experiment Station, P.O. Box 12254, Research Triangle Park, North Carolina)

The US Forest Service, in cooperation with US EPA, instituted a Forest Health Monitoring (FHM) program in 1990. FHM is the repeated recording or sampling of pertinent data for the comparison of that data to reference or identified baseline information. This monitoring involves the determination of changes over time and usually also involves interpretation with respect to a reference or baseline. The goal is to answer the "What, Where, When, How, and Why" of forest health. The program is a three-component approach to collecting, analyzing, and reporting information about the health of all forest lands in the US at several levels of detail. The three components are:

2. Evaluation Monitoring (How)-Determine the specific nature of detected changes and, if possible, the causes. Provides a basis for corrective actions if they are needed. Hypothesizes causes that can be tested experimentally or by information from Intensive-site, Ecosystem Monitoring.

3. Intensive-site, Ecosystem Monitoring (Why)-Provides very high-quality, detailed information to enable a rigorous assessment of cause/effect relationships, to document processes that shape forest ecosystems, and to support experimental research on a small set of sites representing important forest ecosystems.

Research on Monitoring Techniques-A fourth activity that supports all three components is research on the biological, statistical, and analytical aspects of monitoring forest health. This is required to continually improve the effectiveness of FHM.

Status of the Program

Detection Monitoring was implemented in 1990 in the 6 New England states in close cooperation with the State Foresters. About 260 permanent monitoring plots were established and measured. Through FHM, the Forest Service will collect all the needed information for the forest ecosystems component of the EPA's Environmental Monitoring and Assessment Program.

In 1991, Detection Monitoring will be continued in New England and initiated in 6 additional states-New Jersey, Delaware, Maryland, Virginia, Georgia, and Alabama. Detailed plans are being developed for Evaluation Monitoring and Intensive-site, Ecosystem Monitoring. Sites in Oregon, Alaska, and California will probably be initiated in the Intensive-site component of FHM. Decisions are pending on what the Detection Monitoring will actually "measure" in the western US, but candidate "indicators" include visual damage to trees, mensuration, soils, tree cores, mycorrhizal roots, and foliar nutrients. Other physical variables (e.g., hydrologic, geologic, meteorologic) are more likely to be included in the Intensive-site, Ecosystem Monitoring component of the FHM.

Why Forest Health Monitoring?

Public Law 100-521 (the Forest Ecosystem and Atmospheric Pollution Research Act) directs the Forest Service to "increase the frequency of forest inventories in matters that relate to atmospheric pollution and conduct such surveys as are necessary to monitor long-term trends in health and productivity of domestic forest ecosystems....". Public Law 95-313 (the Cooperative Forestry Assistance Act) and Public Law 101-624 (the "1990 Farm Bill") authorize the Forest Service to conduct surveys to detect and appraise induced stresses affecting trees, to monitor all US forests to determine detrimental or beneficial changes over time, and to annually report the monitoring results.