The Forest Inventory and Analysis (FIA) research program has been in existence since mandated by Congress in 1928. FIA's primary objective is to determine the extent, condition, volume, growth, and depletion of timber on the Nation's forest land. Before 1999, all inventories were conducted on a periodic basis. The passage of the 1998 Farm Bill requires FIA to collect data annually on plots within each State. This kind of up-to-date information is essential to frame realistic forest policies and programs. Summary reports for individual States are published but the Forest Service also provides data collected in each inventory to those interested in further analysis. Data is distributed via the FIA DataMart in a standard format. This standard format, referred to as the Forest Inventory and Analysis Database (FIADB) structure, was developed to provide users with as much data as possible in a consistent manner among States. A number of inventories conducted prior to the implementation of the annual inventory are available in the FIADB. However, various data attributes may be empty or the items may have been collected or computed differently. Annual inventories use a common plot design and common data collection procedures nationwide, resulting in greater consistency among FIA work units than earlier inventories. Links to field collection manuals and the FIADB user's manual are provided in the FIA DataMart.
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US Forest Service Forest Inventory and Analysis National Program.
The Forest Inventory and Analysis (FIA) Program of the U.S. Forest Service provides the information needed to assess America's forests.
As the Nation's continuous forest census, our program projects how forests are likely to appear 10 to 50 years from now. This enables us to evaluate whether current forest management practices are sustainable in the long run and to assess whether current policies will allow the next generation to enjoy America's forests as we do today.
FIA reports on status and trends in forest area and location; in the species, size, and health of trees; in total tree growth, mortality, and removals by harvest; in wood production and utilization rates by various products; and in forest land ownership.
The Forest Service has significantly enhanced the FIA program by changing from a periodic survey to an annual survey, by increasing our capacity to analyze and publish data, and by expanding the scope of our data collection to include soil, under story vegetation, tree crown conditions, coarse woody debris, and lichen community composition on a subsample of our plots. The FIA program has also expanded to include the sampling of urban trees on all land use types in select cities.
For more details, see: https://www.fia.fs.fed.us/library/database-documentation/current/ver70/FIADB%20User%20Guide%20P2_7-0_ntc.final.pdf
Fork this kernel to get started with this dataset.
FIA is managed by the Research and Development organization within the USDA Forest Service in cooperation with State and Private Forestry and National Forest Systems. FIA traces it's origin back to the McSweeney - McNary Forest Research Act of 1928 (P.L. 70-466). This law initiated the first inventories starting in 1930.
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Estimating timberland and forest land acres by state.
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Data on Forest Inventory and Analysis (FIA) includes information on Palau's forests 2013-2014. The Pacific Northwest Forest Inventory and Analysis (PNW-FIA) program measures and compiles data on plots in coastal Alaska, California, Hawaii, Oregon, Washington, and U.S.- affiliated Pacific Islands. Most data are available in Access databases and can be downloaded by clicking one of the links below. PNW data are combined with data from all states in the U.S. and stored in the national FIADB. Data for any state can be accessed on the national website (see links to national tools below). Please be aware that some documents may be very large. The PNW-FIA Program shifted from a periodic to an annual inventory system in 2001. Periodic inventories sampled primarily timberland plots outside of national forests and most reserved areas, in a single state within a 2- or 3-year window. Typically, re-assessments occurred every ten years in the West. For the annual inventory in the Pacific Northwest all forested plots are now sampled, with one-tenth of the plots in any given state being visited annually. A full annual inventory cycle is complete in ten years. To download and use the FIA Database, follow this link https://www.fs.fed.us/pnw/rma/fia-topics/inventory-data
This data describe the abundance of individual lichen species across the U.S. as recorded in the Forest Health and Monitoring dataset of the Forest Inventory and Analysis program (i.e. Phase 3 plots). This dataset is not publicly accessible because: These data are already housed on the USFS Forest Inventory and Analysis site (see below). It can be accessed through the following means: The lichen data for this product are from the USDA Forest Services (USFS) Forest Inventory and Analysis (FIA) Phase 3 (P3) dataset - Forest Health and Monitoring. The metadata and database description for the FIA-P3 is here (https://res1wwwd-o-tfiad-o-tfsd-o-tfedd-o-tus.vcapture.xyz/library/database-documentation/). The data itself is located at the USFS Data Mart here (https://res1appsd-o-tfsd-o-tusdad-o-tgov.vcapture.xyz/fia/datamart/CSV/datamart_csv.html) in two files: “LICHEN_PLOT_SUMMARY.zip,” and “LICHEN_VISIT.zip.” Point of contact: Linda Geiser, lgeiser@fs.fed.us. Format: The data are in .csv format.
FIA Modeled Abundance:�This dataset portrays the live tree mean basal area (square feet per acre) of the species across the contiguous United States. The underlying data publication contains raster maps of live tree basal area for each tree species along with corresponding assessment data. An efficient approach for mapping multiple individual tree species over large spatial domains was used to develop these raster datasets. The method integrates vegetation phenology derived from MODIS imagery and raster data describing relevant environmental parameters with extensive field plot data of tree species basal area to create maps of tree species abundance and distribution at a 250-meter (m) pixel size for the contiguous United States. The approach uses the modeling techniques of k-nearest neighbors and canonical correspondence analysis, where model predictions are calculated using a weighting of nearest neighbors based on proximity in a feature space derived from the model. The approach also utilizes a stratification derived from the 2001 National Land-Cover Database tree canopy cover layer.�This data depicts current species abundance and distribution across the contiguous United States, modeled by using FIA field plot data. Although the absolute values associated with the maps differ from species to species, the highest values within each map are always associated with darker colors. The Little's Range Boundaries show the historical tree species ranges across North America. This is a digital representation of maps by Elbert L. Little, Jr., published between 1971 and 1977. These maps were based on botanical lists, forest surveys, field notes and herbarium specimens.Forest-type Groups:This dataset portrays the forest type group. Each group is a subset of the National Forest Type dataset which portrays 28 forest type groups across the contiguous United States. These data were derived from MODIS composite images from the 2002 and 2003 growing seasons in combination with nearly 100 other geospatial data layers, including elevation, slope, aspect, ecoregions, and PRISM climate data.Harvest Growth:This data shows the percentage of timber that is harvested when compared to the total live volume, at a county-by-county level. Timber volume in forests is constantly in flux, and harvest plays an important role in shaping forests. While most counties have some timber harvest, harvest volumes represent low percentages of standing timber volume.Carbon Harvest:The Carbon Harvest raster dataset represents Mg of annual pulpwood harvested (carbon) by county, derived from the Forest Inventory Analysis in 2016.
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This feature class represents forest area estimates (and percent sampling error) by county for the year 2017. The data was generated from the Forest Inventory Analysis (FIA) using the EVALIDator web tool (https://apps.fs.usda.gov/Evalidator/evalidator.jsp). The areas were calculated within county limits using the US Census Bureau's county spatial data (https://www.census.gov/geo/maps-data/data/cbf/cbf_counties.html). Features and attributes of the county layer were adapted to match attributes within the FIA database (FIADB) and features have been generalized by removing vertices to enhance performance. Future iterations of this dataset will be produced using refined methods and higher resolution spatial data. Metadata and Downloads
This feature class represents forest area estimates (and percent sampling error) by county for the year 2018. The data was generated from the Forest Inventory Analysis (FIA) using the EVALIDator web tool (https://apps.fs.usda.gov/Evalidator/evalidator.jsp). The areas were calculated within county limits using the US Census Bureau's county spatial data (https://www.census.gov/geo/maps-data/data/cbf/cbf_counties.html). Features and attributes of the county layer were adapted to match attributes within the FIA database (FIADB) and features have been generalized by removing vertices to enhance performance. Future iterations of this dataset will be produced using refined methods and higher resolution spatial data. Metadata and Downloads
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The United States has been providing national-scale estimates of forest carbon stocks and stock change to meet United Nations Framework Convention on Climate Change reporting requirements for years. Through application of a nearest-neighbor imputation approach, mapped estimates of forest biomass density were developed for the contiguous United States using the annual forest inventory conducted by the USDA Forest Service Forest Inventory and Analysis (FIA) program, MODIS satellite imagery, and ancillary geospatial datasets. This data product would contain the following 7 raster maps: Aboveground Forest Biomass, Belowground Forest Biomass, Forest Tree Bole Biomass, Forest Sapling Biomass, Forest Stump Biomass, Forest Top Biomass, Woodland Specias Biomass. All layers have a 250 meter pixel resolution and values represent biomass pounds per acre. The paper on which these maps are based may be found here: https://dx.doi.org/10.2737/RDS-2013-0004 Access to full metadata and other information can be accessed here: https://dx.doi.org/10.2737/RDS-2013-0004This record was taken from the USDA Enterprise Data Inventory that feeds into the https://data.gov catalog. Data for this record includes the following resources: ISO-19139 metadata ArcGIS Hub Dataset ArcGIS GeoService For complete information, please visit https://data.gov.
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The tree age dataset was derived for tally trees in the Forest Inventory and Analysis program (FIA) of the US Forest Service using an age-size relationship modeling framework that incorporates species-specific and environmental variables.
Associated paper: Lu, J., Huang, C., Schleeweis, K., Zou, Z., & Gong, W. (2025). Tree age estimation across the US using forest inventory and analysis database. Forest Ecology and Management, 584, 122603.
Columns Name | Description |
CN | Tree sequence number |
PLT_CN | Plot sequence number |
INVYR | Inventory year |
Tree_Age | Predicted tree age |
zoneID | ID number indicating the modeling zone where this tree is located, corresponding to the modeling zones in Figure 6 in the paper. |
US_L3CODE | Code indicating the US level-3 ecoregion where this tree is located. |
US_L3NAME | Name of the US level-3 ecoregion where this tree is located. |
State | Two-letter abbreviation for each state. |
This data represents forest area estimates (and percent sampling error) by county for 2015, 2016, and 2017. The data was generated from the Forest Inventory Analysis (FIA) using the EVALIDator web tool (http://apps.fs.fed.us/Evalidator/evalidator.jsp). The areas were calculated within county limits using the US Census Bureau's county spatial data (https://www.census.gov/geo/maps-data/data/cbf/cbf_counties.html). Features and attributes of the county layer were adapted to match attributes within the FIA database (FIADB) and features have been generalized by removing vertices to enhance performance. Future iterations of this dataset will be produced using refined methods and higher resolution spatial data.
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This feature class represents forest area estimates (and percent sampling error) by county for the year 2018. The data was generated from the Forest Inventory Analysis (FIA) using the EVALIDator web tool (https://apps.fs.usda.gov/Evalidator/evalidator.jsp). The areas were calculated within county limits using the US Census Bureau's county spatial data (https://www.census.gov/geographies/mapping-files/time-series/geo/carto-boundary-file.html). Features and attributes of the county layer were adapted to match attributes within the FIA database (FIADB) and features have been generalized by removing vertices to enhance performance. Future iterations of this dataset will be produced using refined methods and higher resolution spatial data. Metadata and DownloadsArea of sampled land and water, in acresArea of forest land, in acresArea of timberland, in acresNumber of live trees (at least 1 inch d.b.h./d.r.c.), in trees, on forest landNumber of live trees (at least 1 inch d.b.h./d.r.c.), in trees, on timberlandNet merchantable bole volume of live trees (at least 5 inches d.b.h./d.r.c.), in cubic feet, on forest landNet merchantable bole volume of live trees (at least 5 inches d.b.h./d.r.c.), in cubic feet, on timberlandSound bole volume of live trees (at least 5 inches d.b.h./d.r.c.), in cubic feet, on forest landAverage annual net growth of sound bole volume of trees (at least 5 inches d.b.h./d.r.c.), in cubic feet, on forest landAverage annual net growth of sound bole volume of trees (at least 5 inches d.b.h./d.r.c.), in cubic feet, on timberlandAverage annual net growth of merchantable bole volume of growing-stock trees (at least 5 inches d.b.h.), in cubic feet, on forest landAverage annual net growth of merchantable bole volume of growing-stock trees (at least 5 inches d.b.h.), in cubic feet, on timberlandAverage annual removals of sound bole volume of trees (at least 5 inches d.b.h./d.r.c.), in cubic feet, on forest landAverage annual removals of sound bole volume of trees (at least 5 inches d.b.h./d.r.c.), in cubic feet, on timberlandAverage annual removals of merchantable bole volume of growing-stock trees (at least 5 inches d.b.h.), in cubic feet, on forest landAverage annual removals of merchantable bole volume of growing-stock trees (at least 5 inches d.b.h.), in cubic feet, on timberlandAverage annual removals of trees (at least 5 inches d.b.h./d.r.c.), in trees, on forest landAverage annual removals of trees (at least 5 inches d.b.h./d.r.c.), in trees, on timberlandAverage annual mortality of sound bole volume of trees (at least 5 inches d.b.h./d.r.c.), in cubic feet, on forest landAverage annual mortality of sound bole volume of trees (at least 5 inches d.b.h./d.r.c.), in cubic feet, on timberlandAverage annual mortality of merchantable bole volume of growing-stock trees (at least 5 inches d.b.h.), in cubic feet, on forest landAverage annual mortality of merchantable bole volume of growing-stock trees (at least 5 inches d.b.h.), in cubic feet, on timberlandAverage annual mortality of trees (at least 5 inches d.b.h./d.r.c.), in trees, on forest landAverage annual mortality of trees (at least 5 inches d.b.h./d.r.c.), in trees, on timberlandAboveground biomass of live trees (at least 1 inch d.b.h./d.r.c), in dry short tons, on forest landAboveground biomass of live trees (at least 1 inch d.b.h./d.r.c), in dry short tons, on timberlandAboveground carbon in live trees (at least 1 inch d.b.h./d.r.c), in short tons, on forest landAboveground carbon in live trees (at least 1 inch d.b.h./d.r.c), in short tons, on timberlandTotal carbon, in short tons, on forest landNet merchantable bole volume of growing-stock trees (at least 5 inches d.b.h.), in cubic feet, on forest landNet merchantable bole volume of growing-stock trees (at least 5 inches d.b.h.), in cubic feet, on timberlandNet sawlog volume of sawtimber trees, in board feet (International 1/4-inch rule), on forest landNet sawlog volume of sawtimber trees, in board feet (International 1/4-inch rule), on timberland
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This feature class represents forest area estimates (and percent sampling error) by county for the year 2019. The data was generated from the Forest Inventory Analysis (FIA) using the EVALIDator web tool (https://apps.fs.usda.gov/Evalidator/evalidator.jsp). The areas were calculated within county limits using the US Census Bureau's county spatial data (https://www.census.gov/geo/maps-data/data/cbf/cbf_counties.html). Features and attributes of the county layer were adapted to match attributes within the FIA database (FIADB) and features have been generalized by removing vertices to enhance performance. Future iterations of this dataset will be produced using refined methods and higher resolution spatial data. Metadata and Downloads
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This feature class represents forest area estimates (and percent sampling error) by county for the year 2016. The data was generated from the Forest Inventory Analysis (FIA) using the EVALIDator web tool (https://apps.fs.usda.gov/Evalidator/evalidator.jsp). The areas were calculated within county limits using the US Census Bureau's county spatial data (https://www.census.gov/geo/maps-data/data/cbf/cbf_counties.html). Features and attributes of the county layer were adapted to match attributes within the FIA database (FIADB) and features have been generalized by removing vertices to enhance performance. Future iterations of this dataset will be produced using refined methods and higher resolution spatial data. Metadata and Downloads
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The Forest and Inventory database (FIADB) can be used to produce information on a wide variety of forest statistics including forest area, numbers of trees, tree biomass, tree volume, volume of growth, volume of mortality, and volume harvested. These statistics can be categorized by different data elements. The area estimates, for example, can be categorized by county, forest type, ownership, and stand-size, while estimates for numbers of trees, biomass, and volume can additionally be categorized by tree species, and tree diameter. The FIADB structure was developed to provide users with as much data as possible in a consistent manner among States. Frequency of data collection for individual states has varied over time. Annual inventories use a common plot design and common data collection procedures nationwide, resulting in greater consistency among FIA work units than earlier inventories. Many inventories conducted prior to the implementation of the annual inventory are available in the FIADB - the earliest dating back to 1968. However, various data attributes may be nulled or the items may have been collected or computed differently. Data are distributed via the FIA DataMart in the FIADB structure as well as a number of derived structures, reflecting pre-defined subsets of FIADB. Links to field collection manuals and the FIADB user's manual are provided in this metadata document.The Forest Inventory and Analysis (FIA) research program has been in existence since mandated by Congress in 1928. FIA’s primary objective is to determine the extent, condition, volume, growth, and depletion of timber on the Nation’s forest land. Before 1999, all inventories were conducted on a periodic basis. The 1998 Farm Bill required FIA to collect data annually on plots within each State. This kind of up-to-date information is essential to frame realistic forest policies and programs. In addition to the data, summary reports for individual States are published.To protect the integrity of the FIA sample, the exact coordinates of our sample plot locations are kept confidential. This protects the privacy of landowners who allow FIA field crews on their land, as well as protects the plots from any tampering. This policy of location confidentiality is incorporated into law through the Fiscal Year 2000 Consolidated Appropriations Bill (PL 106-113) which amended the Food Security Act of 1985 (7 U.S.C. 2276(d)) to include FIA data to the list of items that require confidential treatment.
The original date for this metadata document is 07/18/2019. On 07/29/2022 minor metadata updates were made, which included the correction of old URLs where possible.
This feature service is based on ESRI's USA Counties layer (available here) that has been subset to the USDA Forest Service, Northern Research Station (NRS), Forest Inventory and Analysis (FIA) region (24 states). Features and attributes of ESRI's layer have been adapted to match attributes within the FIA database (FIADB) and features have been generalized by removing vertices to enhance performance. This layer has been attributed with outputs from FIA's EVALIDator tool (https://apps.fs.usda.gov/fiadb-api/evalidator) for the following estimates:Area of forest land, in thousands of acresArea of timber land, in thousands of acresNet volume of live trees (at least 5 inches d.b.h./d.r.c.), in cubic feet, on forest landAverage annual net growth of live trees (at least 5 inches d.b.h./d.r.c.), in cubic feet, on forest landAverage annual removals of live trees (at least 5 inches d.b.h./d.r.c.), in cubic feet, on forest landAverage annual mortality of trees (at least 5 inches d.b.h./d.r.c.), in trees, on forest landAboveground dry weight of live trees (at least 1 inch d.b.h./d.r.c), in short tons, on forest landAboveground carbon in live treesTotal carbon, in short tons, on forest landNet volume of growing-stock trees (at least 5 inches d.b.h.), in cubic feet, on timberlandNet volume of sawtimber trees, in board feet (International 1/4-inch rule), on timberlandRatios have also been calculated for area of forest land to total land area and area of timber land to total land area.States without available data are omitted and will be updated as data become available.Additional data descriptions are available in the most recent FIADB User Manual, available here.
Nonnative invasive plant species cause long-term detrimental effects on forest ecosystems, including declines in biological diversity, alterations to forest succession, and changes in nutrient, carbon, and water cycles. The damage caused by these exotic species, and the efforts to control them, are costly, even before accounting for the impacts to nonmarket economic services such as recreation and landscape aesthetics. The Forest Inventory and Analysis (FIA) program collects invasive plant data based on expert-derived lists of problematic invasive plant species defined as those of any growth form likely to cause economic or environmental harm. Using each state's most recent evaluation period between 2005 and 2018, we determined the number and percent of FIA plots invaded by non-native plant species for each U.S. county, as well as the mean number of invasive species and percent cover of invasive species on the plots inventoried for invasive species in each county. These county-level data are provided as both a shapefile and Geopackage.These data were developed to assess the degree of invasion of U.S. forests by non-native plants for the 2020 Resources Planning Act (RPA) Assessment (https://www.fs.usda.gov/research/inventory/rpaa) chapter on Disturbances to Forests and Rangelands.These data were published on 03/10/2023. Metadata updated on 10/17/2023 to include reference to published RPA Assessment.
This dataset provides forest biomass estimates for the conterminous United States based on data from the USDA Forest Inventory and Analysis (FIA) program. FIA maintains uniformly measured field plots across the conterminous U.S. This dataset, derived from field survey data from 2009-2019, includes statistical estimates of biomass at the finest scale (64,000-hectare hexagons) allowed by FIA's sample density. Estimates include the mean (and standard error of the mean) biomass for both live and dead trees, calculated using three sets of allometric equations. There is also an estimate of the area of forestland in each hexagon. These data can be useful for assessing the accuracy of remotely sensed biomass estimates.
I obtained inventory data from the USDA Forest Inventory and Analysis (FIA) program, covering 1999 to 2022, focusing on eight southeastern states in the U.S. (Alabama, Mississippi, Florida, Georgia, North Carolina, South Carolina, Texas, and Louisiana). For this study, I filtered the data for 2015-2019, during which the FIA captures 20% of plots in each state annually. Using R, I converted aboveground biomass (AGB) from pounds to kg/ha, tree height from feet to meters, and diameter at breast height (DBH) from inches to centimeters to align with the metric system. Structural diversity of tree height and diameter was calculated using the Shannon diversity index based on tree height and diameter classes. Climate data from PRISM and soil carbon to nitrogen data from the World Soil Database were integrated with the FIA data using the nearest neighbors method in the SF package in R. The combined dataset was standardized for Structural Equation Modeling (SEM) analysis.
Basal Area (BA). 30 meter pixel resolution. Data represents forest conditions circa 2002.These data are a product of a multi-year effort by the FHTET (Forest Health Technology Enterprise Team) Remote Sensing Program to develop raster datasets of forest parameters for each of the tree species measured in the Forest Service’s Forest Inventory and Analysis (FIA) program. This dataset was created to support the 2013–2027 National Insect and Disease Risk Map (NIDRM) assessment. The statistical modeling approach used data-mining software and an archive of geospatial information to find the complex relationships between GIS layers and the presence/abundance of tree species as measured in over 300,000 FIA plot locations. Unique statistical models were developed from predictor layers consisting of climate, terrain, soils, and satellite imagery. Modeled basal area (BA) and stand density index (SDI) datasets for individual tree species were further post-processed to 1) match BA and SDI histograms of FIA data, 2) ensure that the sum of individual species BA and SDI on a pixel did not exceed separately modeled total for all species BA and SDI raster datasets, 3) derive additional tree parameters like quadratic mean diameter and trees per acre. With Landsat image collection dates ranging from 1985 to 2005, and a mean collection date for treed areas of 2002, and FIA plot data generally ranging from 1999 to 2005, the vintage of the base parameter datasets varies based on location, but can be roughly considered as 2002
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Open the Data Resource: https://research.fs.usda.gov/products/dataandtools/tools/fia-datamart The Forest Inventory and Analysis program of the USDA Forest Service Research and Development Branch collects, processes, analyzes and reports on data necessary for assessing the extent and condition of forest resources in the United States. The FIA DataMart allows visitors to download raw FIA data in comma delimited tables, SQLite databases and customizable batch estimate workbooks. The DataMart map also provides a quick visual reference for the most recent data available for each state or inventory area.
The Forest Inventory and Analysis (FIA) research program has been in existence since mandated by Congress in 1928. FIA's primary objective is to determine the extent, condition, volume, growth, and depletion of timber on the Nation's forest land. Before 1999, all inventories were conducted on a periodic basis. The passage of the 1998 Farm Bill requires FIA to collect data annually on plots within each State. This kind of up-to-date information is essential to frame realistic forest policies and programs. Summary reports for individual States are published but the Forest Service also provides data collected in each inventory to those interested in further analysis. Data is distributed via the FIA DataMart in a standard format. This standard format, referred to as the Forest Inventory and Analysis Database (FIADB) structure, was developed to provide users with as much data as possible in a consistent manner among States. A number of inventories conducted prior to the implementation of the annual inventory are available in the FIADB. However, various data attributes may be empty or the items may have been collected or computed differently. Annual inventories use a common plot design and common data collection procedures nationwide, resulting in greater consistency among FIA work units than earlier inventories. Links to field collection manuals and the FIADB user's manual are provided in the FIA DataMart.