Anderson's thistle (Cirsium andersonii) is in the Sunflowers, Daisies, Asters, and Allies family (Asteraceae). Across the U.S., iNaturalist users have logged 1,356 research-grade flowering observations of it in our sample, peaking in July.
Nationally it blooms mainly from July to September, but timing varies a lot by state and elevation — see the table below.
When to photograph Anderson's thistle: observations by month (U.S.)
About Anderson's thistle
Cirsium andersonii is a North American species of thistle known by the common names Anderson's thistle and rose thistle. It is native to California, Oregon, and Nevada, where it grows in the woodlands and forest openings of the local high mountain ranges, including the Sierra Nevada and the southern Cascade Range. It has also been reported from Idaho.From Wikipedia via iNaturalist — article, CC BY-SA.
Anderson's thistle by state
| State | Observations | Peak month | Main season |
|---|---|---|---|
| California | 1,284 | July | Jul–Sep |
| Nevada | 72 | July | Jul–Sep |
Main season = months with at least 30% of the state's peak-month count.
Related wildflowers (Sunflowers, Daisies, Asters, and Allies)
black-eyed Susan
Common Yarrow
White Snakeroot
Chicory
Lawn daisy
Philadelphia fleabane
Pearly Everlasting
Blue Mistflower
Photography tips
- Photograph flowers on calm, overcast mornings to avoid wind blur and harsh shadows.
- Get low: a shallow depth of field (f/2.8–f/5.6) isolates a bloom against soft color.
- Stay on trails — trampling meadows kills plants and ruins next year's display.
- Try a kaleidoscope abstract of a single bloom with our online kaleidoscope tool.
FAQ
When is the best time to photograph Anderson's thistle?
Nationally, July has the most observations, with the main season from July to September.
Where is Anderson's thistle most often seen?
The most observations come from California, Nevada.