Data Sources & Attribution

Last Updated: August 15, 2026

Flora API is compiled from public botanical databases and federal government sources. This page lists those sources, the licenses that apply, and what you need to do when you redistribute data obtained through the API.

The same information is available in machine-readable form: every bulk export includes an attribution object (JSON) or an ATTRIBUTION.txt file (CSV/ZIP).

The short version

Most of what Flora API serves is public-domain federal data or original work, and carries no attribution requirement. Two things do:

  • Climate data — PRISM and MACAv2 ask to be cited.
  • Photographs — most are CC BY or CC BY-SA, which require credit. Each image carries its own license and attribution fields — carry them forward.

1. Species Taxonomy & Distribution

USDA PLANTS Database

County-level species occurrence records, USDA plant symbols, native and introduced status by region, and taxonomic classification. The county distribution data is the foundation of Flora's climate viability analysis — it is what tells the model where each species actually grows.

License: Public domain. USDA states that its plant information is not copyrighted and is free for any use.

Citation: USDA, NRCS. The PLANTS Database. National Plant Data Team, Greensboro, NC. https://plants.usda.gov/

Taxonomic cross-reference

Scientific nomenclature is cross-referenced against three taxonomic authorities for consistency:

Conservation status ranks

Global conservation status ranks (G1–G5, T1–T5) originate with NatureServe and its network of member programs. https://www.natureserve.org/

Ranks are point-in-time assessments and may lag NatureServe’s current data; consult NatureServe Explorer for the authoritative current rank. The threat-level descriptions and regulatory flags Flora returns alongside a rank are Flora API’s own interpretation, not NatureServe’s.

Additional botanical attributes

Morphology, foliage characteristics, bloom timing, growing conditions, and wildlife interactions were aggregated from public botanical databases and government sources. These are factual attributes of the plants themselves.

2. Climate Data

PRISM Climate Group — current climate

All current-climate measurements derive from PRISM 30-year normals (1991–2020): temperature, precipitation, and vapor pressure deficit, from which Flora computes heat days, growing degree days, frost-free days, chill hours, and the 19 standard bioclimatic variables. These populate Flora's ZIP-code-level and county-level climate profiles.

Citation: PRISM Climate Group, Oregon State University. https://prism.oregonstate.edu/

Flora publishes aggregate statistics derived from PRISM data (ZIP-code and county means and the variables computed from them). It does not redistribute the underlying PRISM raster grids.

MACAv2-METDATA — future projections

Climate projections for the 2050s and 2080s under RCP 4.5 and RCP 8.5, drawn from a 20-model ensemble downscaled to roughly 4-kilometer resolution across the contiguous United States.

Citation: Abatzoglou, J.T. & Brown, T.J. (2012). A comparison of statistical downscaling methods suited for wildfire applications. International Journal of Climatology, 32(5), 772–780. Accessed via Google Earth Engine.

US Census Bureau — geographies

County and ZIP Code Tabulation Area boundaries, and the ZIP-to-ZCTA crosswalk.

License: Public domain. Citation: U.S. Census Bureau, TIGER/Line Shapefiles.

3. Photographs

Flora serves roughly 123,000 species photographs from two sources:

  • Wikimedia Commons (~112,000 images) — individually licensed by their contributors under CC0, CC BY, or CC BY-SA. https://commons.wikimedia.org/
  • USDA PLANTS (~11,000 images) — public domain.

Attribution is a license condition, not a courtesy. The majority of Flora's photographs are CC BY or CC BY-SA. If you display or redistribute them, you must credit the photographer. CC BY-SA additionally requires that derivative works be shared under the same license.

How to comply

Every image record returned by GET /v1/species/{id}/images carries the fields you need:

  • license — cc0, cc-by, cc-by-sa, or public_domain
  • attribution — the photographer or contributor to credit
  • attribution_required — a boolean you can branch on
  • source_page_url — the original file page, for a link back

Bulk exports include image_license and image_attribution columns alongside every image URL for the same reason.

A compliant credit line looks like:

Photo by {attribution}, via Wikimedia Commons, licensed under CC BY-SA 4.0.

If you would rather avoid attribution obligations entirely, pass exclude_attribution=true to the images endpoint to receive only images that carry no such requirement.

4. Flora API's Own Work

The following are original to Flora API and are not derived from any third-party source:

  • Species climate envelopes — the observed tolerance range of each species across 27 climate variables, computed by intersecting USDA county distribution with PRISM county climate.
  • The viability scoring model — the weighted, multi-variable comparison of a location's climate against a species' envelope, under current and projected conditions.
  • Species descriptions — generated from the structured factual attributes in the database.
  • The API schema and data model.

Use of these is governed by the Terms of Service.

5. Copy-and-paste attribution

If you publish work built on Flora API data, this block satisfies every citation request and license condition above:

Data sources:

Species distribution and taxonomy — USDA NRCS PLANTS Database
  (https://plants.usda.gov/). Public domain.
Current climate normals — PRISM Climate Group, Oregon State University
  (https://prism.oregonstate.edu/), 1991-2020 30-year normals.
Climate projections — MACAv2-METDATA (Abatzoglou & Brown 2012),
  via Google Earth Engine.
County and ZCTA geographies — US Census Bureau TIGER/Line.
Taxonomic cross-reference — ITIS (https://www.itis.gov/),
  Catalogue of Life, World Flora Online.
Conservation status ranks — NatureServe (https://www.natureserve.org/).
Photographs — Wikimedia Commons contributors, individually licensed
  (CC0 / CC BY / CC BY-SA); see per-image license and attribution fields.
  USDA PLANTS photographs are public domain.

Climate viability envelopes, the 27-variable scoring model, and generated
species descriptions are original work of Flora API.

6. Questions & corrections

If you believe a source is mis-attributed, a license is recorded incorrectly, or your work appears without proper credit, contact us at support@floraapi.com and we will correct it.