How to Identify Wildflowers on U.S. Wildflowers by State and Family
U.S. Wildflowers (uswildflowers.com) is a free photo-and-description reference for wildflowers of the United States, built around 2,387 photographs covering 649 species. You can use it to narrow a mystery flower down by state first, then by plant family, then by scanning thumbnails until a candidate matches. The site's own author states plainly that he is "not a professional botanist" and that some identifications are likely incorrect, so treat any match here as a strong lead to confirm elsewhere, not a final verdict.
What the site actually gives you
Before you start clicking, know which tool does what:
| Resource | What it contains | Best used for |
|---|---|---|
| State Reference List | Species lists filtered to a specific state | Cutting the 649 species down to what actually grows near you |
| Family Index | Database index organized by plant family | Working from a family you already suspect (e.g., a mint, a pea, an aster) |
| Thumbnail list | 649 species as thumbnails without descriptions | Fast visual scanning when you have no idea what family it is |
| Wildflower list | Thumbnails plus descriptions for all 649 species | Reading detail once you have a shortlist |
| Detail pages | Photos, description, and distribution information per species | Confirming or rejecting a candidate |
| Journal and photo albums | Additional photographs beyond the detail pages | Seeing the plant in different conditions and locations |
Note that the 649 figure counts some subspecies separately, and the site also includes a few non-flowering plants of interest, such as Ground Cedar.
Step 1: Narrow by state
Start here rather than with the full list. The site provides a state selector with entries such as Alabama, Alaska, Arkansas, Arizona, and California wildflower ID references, and the same pattern continues across states.
- Choose the state where you photographed the flower.
- Use the resulting state list as your working set instead of all 649 species.
- If you saw the plant near a state border, check both states — distribution lists are not a guarantee of absence.
This single step removes the largest source of wrong answers, because most mismatches come from species that simply do not occur in your region.
Step 2: Narrow by family (if you have a hunch)
If the flower's structure suggests a family — square stems and opposite leaves pointing toward the mint family, pea-like blossoms toward the legume family, composite heads toward the aster family — go through the Family Index instead.
- Open the Family Index.
- Pick the family you suspect.
- Compare the species shown against your photo.
If you have no family hunch, skip to Step 3. Guessing a family you are unsure of can send you down a long dead end.
Step 3: Scan thumbnails
The thumbnail list exists precisely for this: the author notes he finds it easier to scan for a particular flower than the full described list. Use it when you are working visually.
- Open the thumbnail list, or the state-filtered version if you completed Step 1.
- Scan for color, flower shape, and leaf arrangement rather than exact matches.
- Collect two or three candidates — do not stop at the first plausible one.
The full Wildflower list (thumbnails with descriptions) is the heavier alternative; the author flags it as a long-running, resource-intensive page, so prefer the thumbnail view for scanning and save the described list for verification.
Step 4: Confirm on the detail page
For each candidate, open its detail page and check the photo against your own image on these points:
- Flower color and number of petals or ray flowers
- Leaf shape, arrangement (alternate, opposite, whorled), and edge
- Overall habit — upright, trailing, rosette-forming
- Stated distribution, to confirm it fits your location
If two candidates both fit, look for a distinguishing feature the descriptions call out, such as hairiness, flower size, or bloom season. Bloom timing is often the tiebreaker between similar species.
Step 5: Verify beyond this site
Because the site's identifications are explicitly non-authoritative, close the loop with a second source:
- A state native plant society checklist
- A university extension or herbarium database for your region
- A local botanist or a regional flora guide
If your candidate survives a second source, you can record it with reasonable confidence.
Common snags
- Subspecies counted separately. A species may appear more than once under different subspecies names, so a "missing" plant may be listed under a variant.
- Non-flowering entries. Ground Cedar and similar plants appear here even though they are not wildflowers, so do not assume every entry blooms.
- Photo conditions vary. Lighting, bloom stage, and camera angle change appearance significantly; compare structure, not just color.
- State lists are references, not surveys. A species absent from your state's list may still occur there at the edge of its range.
- The list is one hobbyist's work. Coverage is broad but not exhaustive, and errors exist. Absence from the site is not evidence a plant is rare or unidentified.
A practical workflow
Photograph the flower with leaves, stem, and surrounding habitat in frame. Note the state and the date. Filter by state, scan thumbnails for two or three candidates, open each detail page, and compare structure and distribution. Then confirm against one independent regional source before you write the name down.