Castilleja linariifolia (Wyoming Indian paintbrush)

Plate 1 figs. a–h · 8 separate observations

Castilleja linariifolia, photographed by Caleb Catto — fig. a Caleb Catto, CC BY 4.0 / 2021-12-02 / obs. 171141863

Castilleja linariifolia, photographed by Jay Pruett — fig. c Jay Pruett, CC BY 4.0 / obs. 169168917

Castilleja linariifolia, photographed by Steve Matson — fig. d Steve Matson, CC BY 4.0 / obs. 160561266

Castilleja linariifolia, photographed by rappman — fig. e rappman, CC BY 4.0 / obs. 160730896

Castilleja linariifolia, photographed by Bobby McCabe — fig. g Bobby McCabe, CC BY 4.0 / obs. 158697429

Castilleja linariifolia, photographed by sprcrkwild — fig. h sprcrkwild, CC BY 4.0 / obs. 158663085

Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.

Native range 10 botanical countries

Native distribution of Castilleja linariifolia, after Kew’s World Checklist of Vascular Plants. Introduced, extinct and doubtful records are excluded, so this is where the plant is from, not everywhere it now grows.

Region	TDWG code	Continent
Arizona	ARI	NORTHERN AMERICA
California	CAL
Colorado	COL
Idaho	IDA
Montana	MNT
Nevada	NEV
New Mexico	NWM
Oregon	ORE
Utah	UTA
Wyoming	WYO

Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.

Flowering 454 in flower of 483 examined

100%

89%

93%

100%

94%

100%

Proportion of examined Castilleja linariifolia in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	0	0	too few examined
Feb	0	0	too few examined
Mar	0	0	too few examined
Apr	1	2	too few examined
May	5	5	100%	57% to 100%
Jun	93	104	89%	82% to 94%
Jul	166	179	93%	88% to 96%
Aug	73	73	100%	95% to 100%
Sep	62	66	94%	85% to 98%
Oct	42	42	100%	92% to 100%
Nov	12	12	100%	76% to 100%
Dec	0	0	too few examined

Peak flowering in May. Each bar is the share of Castilleja linariifolia observations in which someone actually recorded the reproductive state and found the plant in flower, not the raw number of flowering records. That distinction matters: people observe plants far more in spring than in winter, so a bare count of flowering records partly measures when people go outside. Dividing by the number examined removes that. 454 of 483 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 5 months have fewer than 5 examined observations, so no proportion is drawn for them. This is still a global aggregate and not a forecast for your garden: the same species flowers on different dates in different hemispheres. Where a species has fewer than 30 flowering records we do not draw this chart at all. Computed from 10.15468/dl.cgje2x.

Where it actually grows measured, from 2,011 observations

Condition	5th percentile	Median	95th percentile
Coldest month, mean daily low	-15.9 °C	-10.5 °C	-3.1 °C
Warmest month, mean daily high	20.3 °C	25.8 °C	33.3 °C
Annual rainfall	218 mm	467 mm	1,022 mm
Rainfall in the driest quarter	30 mm	62 mm	176 mm

It is found where winters are severely cold. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 2,011 research-grade observations of Castilleja linariifolia that carry a coordinate, and this is the range those places actually span. The 5th and 95th percentiles are used rather than the minimum and maximum, because a single cultivated specimen in a heated conservatory should not widen a tropical plant's range to the Arctic.

This is not a hardiness zone. A USDA zone is the average annual extreme minimum temperature. The figure above is the mean daily minimum of the coldest month, which is a different quantity and is typically far warmer. Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one. Climate from CHELSA V2.1 (Karger et al. 2017); occurrences from 10.15468/dl.cgje2x.

Also published as 12 synonyms

A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.

Castilleja affinis var. linariifolia (Benth.) Zeile
Castilleja arcuata Rydb.
Castilleja candens Durand & Hilg.
Castilleja fulgens Nutt. ex A.Gray
Castilleja howellii Eastw.
Castilleja linariifolia f. omnipubescens Pennell
Castilleja linariifolia f. rosea Cockerell
Castilleja linariifolia var. filiformis Daniels
Castilleja linariifolia var. omnipubescens (Pennell) Clokey
Castilleja linearis Rydb.
Castilleja salticola Eastw.
Castilleja trainii Edwin

Sourcesevery claim on this page

World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.

We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite.