generated: '2026-09-10'
method: probed
source: >-
  Response headers observed on live unauthenticated calls to every Forest Service API surface,
  plus a documentation search across the FIADB-API docs, the Research Data Archive API PDF and
  the FSGeodata Clearinghouse help pages, 2026-09-10.
limit_count: 0
note: >-
  An honest zero. The Forest Service documents no rate limit for any of its four public APIs, and
  no surface returns a rate-limit header of any kind — no X-RateLimit-*, no RateLimit-*, no
  Retry-After — on a successful or a failed response. That is not the same as unlimited: a caller
  has no published budget and no runtime signal, so the only safe assumption for an automated
  client is that throttling, if it exists, will arrive without warning at the edge (Azure Front
  Door in front of www.fs.usda.gov, an F5 load balancer in front of the archive service) rather
  than from the application. Politeness has to be self-imposed.
rate_limits: []
observed_headers:
  - api: Forest Service Research Data Archive Web Service
    url: https://www.fs.usda.gov/rds/archive/webservice/efrs
    http_status: 200
    rate_limit_headers: []
    present: [date, content-type, cache-control, pragma, expires, set-cookie, x-frame-options, strict-transport-security, x-azure-ref, x-cache, accept-ranges]
  - api: FIADB-API / EVALIDator
    url: https://apps.fs.usda.gov/fiadb-api/fullreport?rselected=Land%20Use%20-%20Major&cselected=Land%20use&snum=79&wc=102020&outputFormat=NJSON
    http_status: 200
    rate_limit_headers: []
    present: [date, content-type, content-length, connection, access-control-allow-origin, content-security-policy, x-frame-options, vary, set-cookie, strict-transport-security]
  - api: FSGeodata ArcGIS REST services
    url: https://apps.fs.usda.gov/arcx/rest/services?f=json
    http_status: 200
    rate_limit_headers: []
exhaustion_status_code: null
documentation_searched:
  - url: https://apps.fs.usda.gov/fiadb-api/
    status: 200
    result: no limits stated
  - url: https://www.fs.usda.gov/rds/archive/webservice/assets/ResearchDataArchiveAPIDocumentation.pdf
    status: 200
    result: >-
      12-page API document covering global settings, /search, /product, /organizations and /efrs.
      No rate limit, quota or throttling section.
  - url: https://data.fs.usda.gov/geodata/help.php
    status: 200
    result: no limits stated
practical_ceiling:
  detail: >-
    The one soft ceiling actually documented is a page-size default, not a rate: Research Data
    Archive /search returns 10 rows unless `rows` is raised. Query cost is visible in the
    response — every archive response echoes QTime (0.007-0.077 s across the calls we made) and
    the FIADB-API returned a 34 KB estimate set in a single request.