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Forest Ecosystem Health Indicators

Abstract

The U.S. Department of Agriculture (USDA), Forest Service, Forest Inventory and Analysis (FIA) 
Program is the Nation’s continuous forest census. Since 1930, we have collected, analyzed, and 
reported information on the status and trends of America’s forests: how much forest exists, where 
it exists, who owns it, and how it is changing — growing, dying, being harvested, or converted to 
and from forest land uses. In response to widening customer interests, the FIA developed a program 
that was implemented in the same manner on all U.S. forest lands. This included sampling an 
extended suite of forest health indicators. Many of these indicators were developed and initially 
measured by the Forest Health Monitoring (FHM) Program in the 1990s. In 1999, they were transferred to FIA and now are a subset of the FIA inventory.

Originally, the health indicators were sampled on 1 of every 16 standard FIA plots, but this design 
faced budget and logistical constraints. In 2012, FIA redesigned the health program as a flexible 
system with spatial and temporal intensities that are adaptable to meet budgetary constraints, 
client needs, and regional issues. A minimum national set of protocols are “core” to the 
forest/ecosystem health indicator program. These health indicators are collected at intensities ranging from a minimum of approximately 7 percent up to 25 percent of the standard plot grid. In addition, the Vegetation Profile and Down Woody Materials indicators are sampled on all plots in the Western United States. 

The FIA indicators discussed in this publication are:

  • Crown Condition (KaDonna C. Randolph)
  • Tree Damage (Randall S. Morin and Kerry Dooley)
  • Tree Mortality and Standing Dead Trees (Randall S. Morin and Mark D. Nelson)
  • Lichen Communities (Sarah Jovan) (adjunct inventory conducted by National Forest Systems in some regions; retired as a national core indicator)
  • Down Woody Materials (Christopher W. Woodall)
  • Vegetation Profile (Bethany K. Schulz)
  • Soil Quality (Charles H. Perry)
  • Nonnative Invasive Plants (Cassandra M. Kurtz and Sonja N. Oswalt)
  • Regeneration and Browse Impact (William H. McWilliams)
  • Fragmentation and Landscape Context (Rachel Riemann) 
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Download (PDF 3.30MB): https://research.fs.usda.gov/sites/default/files/2024-07/wo-17827_forest_service_forest_ecosystem_health_indicators_508.pdf
Last updated July 30, 2024