# U.S. Forest Service > The Forest Service is an agency of the U.S. Department of Agriculture that manages > 193 million acres of national forests and grasslands. It is not a software vendor, but it > operates four public, free, entirely unauthenticated HTTP APIs — forest inventory estimation, > a research data archive with an OAI-PMH repository, and two enterprise geospatial map service > catalogs. This file was generated by API Evangelist from live probes of those surfaces on > 2026-09-10; the Forest Service does not publish an llms.txt of its own. ## What an agent needs to know first - No API key, token, account or registration exists for any surface. Every call below was made anonymously with curl. - Every operation is a read. There is no write, create, update or delete anywhere in the public estate. - There is no OpenAPI description for any of these APIs. Endpoints and parameters below come from the agency's own documentation and from calls that returned 200. - Failed requests do not reliably return a failing HTTP status. The ArcGIS servers answer 200 with a JSON `error` object; the FIADB-API answers 200 with an HTML error page even when JSON was requested. Check the body, not the status. - No rate limits are published and no rate-limit headers are returned. Throttle yourself. ## Forest Inventory and Analysis — FIADB-API / EVALIDator Base: https://apps.fs.usda.gov/fiadb-api - [FIADB-API documentation](https://apps.fs.usda.gov/fiadb-api/): parameter reference for the estimation endpoints, with worked Python (`requests`) and R (`httr`) GET and POST examples. - `GET|POST /fullreport`: the primary FIA Phase 2 estimate endpoint. Returns population estimates with sampling errors, plot counts and variance. Required: `snum` (estimate attribute), `wc` (evaluation group code, typically state FIPS + inventory year, e.g. 102020 for Delaware 2020), `rselected` (row grouping), `cselected` (column grouping). Pass `outputFormat=NJSON` for flat JSON with metadata. Optional `strFilter` takes a SQL fragment such as `COND.OWNCD = 40`. - `GET /fullreport/parameters/{name}`: the value dictionary for a classed parameter. Resolve `snum`, `wc`, `rselected` and `cselected` here before calling `/fullreport`. - `GET /urban`: the Urban FIADB-API. - Every response embeds a `citation` string and a `metadata` object containing the generated SQL. - Contact: SM.FS.FIA.Digital@usda.gov ## Research Data Archive Web Service Base: https://www.fs.usda.gov/rds/archive/webservice - [Service page and release notes](https://www.fs.usda.gov/rds/archive/webservice/) - [API documentation PDF](https://www.fs.usda.gov/rds/archive/webservice/assets/ResearchDataArchiveAPIDocumentation.pdf) - `GET /search`: find data publications. `query`, `funder`, `efr`, `page`, `rows` (default 10), `sort` (`date` or `score`). Response echoes `numFound`, `page`, `start`, `rows`. - `GET /product?id=RDS-YYYY-NNNN`: one data publication with DOI, abstract, authors, funders, keywords, places and bounding coordinates. - `GET /organizations`: the 405 funder organizations usable in `funder`, with Crossref Funder Registry ids. - `GET /efrs`: the 32 Experimental Forests and Ranges usable in `efr`, with product counts. - `GET /oaipmh?verb=...`: an OAI-PMH 2.0 repository. Metadata prefixes `oai_dc` (Dublin Core) and `fgdc` (FGDC-STD-001.1-1999). Earliest datestamp 2016-02-22, no deleted records, gzip supported. - Add `format=json` to any of the four REST endpoints; the default is XML. The Accept header is ignored. - Every product carries a DOI under the 10.2737 prefix. ## FSGeodata enterprise map services (ArcGIS REST) Base: https://apps.fs.usda.gov/arcx/rest/services (Enterprise Data Warehouse and research data) Base: https://apps.fs.usda.gov/fsgisx01/rest/services (additional research data warehouse folders) - [FSGeodata Clearinghouse](https://data.fs.usda.gov/geodata/) - [Map Services documentation](https://data.fs.usda.gov/geodata/edw/mapServices.php) - `GET /?f=json` lists nine folders: EDW, RDW_AdminAndOwnership, RDW_Climate, RDW_FIA_ForestAtlas, RDW_InventoryAndProducts, RDW_LandscapeAndWildlife, RDW_Wildfire, Utilities, wo_nrm_iweb. - `GET /EDW?f=json` enumerates 144 MapServer services — ownership, boundaries, activities, fire retardant avoidance areas, aquatic organism passage, ecoregions and more. - `GET /{folder}/{service}/MapServer?f=json` returns the service document: description, copyright, capabilities, layers, and a link to the dataset's FGDC metadata XML under https://data.fs.usda.gov/geodata/edw/edw_resources/meta/ - Each service also exposes a SOAP contract at https://apps.fs.usda.gov/arcx/services/{folder}/{service}/MapServer?wsdl (WSDL 1.1, 55 operations). - OGC WMS/WFS is NOT enabled on these servers — GetCapabilities returns HTTP 400. Access is ArcGIS REST or SOAP. ## Geospatial Data Discovery and open data catalogs - [Geospatial Data Discovery](https://data-usfs.hub.arcgis.com/) - `GET https://data-usfs.hub.arcgis.com/api/feed/dcat-us/1.1.json` — the agency's machine-readable DCAT-US 1.1 / Project Open Data dataset catalog (~2 MB). - [Forest Service datasets on Data.gov](https://catalog.data.gov/organization/352b4532-793d-4075-a03f-05b778a3c43a?publisher=U.S.+Forest+Service&_publisher_limit=0&page=1) ## Agency software - [FIESTA](https://cran.r-project.org/package=FIESTA) — R package for FIA estimation, 3.7.1 (2025-03-26), maintained at github.com/USDAForestService/FIESTA. - [FIESTAutils](https://cran.r-project.org/package=FIESTAutils) — 1.3.2 (2025-07-17). - [Forest Vegetation Simulator](https://github.com/USDAForestService/ForestVegetationSimulator) — growth-and-yield modelling software. - None of these is a client library for the HTTP APIs above. ## Terms and citation - The data are works of the U.S. government and are free to use; the agency asks for citation. - [Disclaimers and important notices](https://www.fs.usda.gov/about-agency/disclaimers-important-notices) — the map data are explicitly not legal documents and may not be used to determine title, ownership, legal boundaries or jurisdiction. ## Optional - [Forest Service GitHub organization](https://github.com/USDAForestService) - [Data, Tools and Products](https://www.fs.usda.gov/science-technology/data-tools-products) - [FSGeodata contact](https://data.fs.usda.gov/geodata/contactus.php)