| Castilleja exserta | |
|---|---|
![]()  | |
| Scientific classification  | |
| Kingdom: | Plantae | 
| Clade: | Tracheophytes | 
| Clade: | Angiosperms | 
| Clade: | Eudicots | 
| Clade: | Asterids | 
| Order: | Lamiales | 
| Family: | Orobanchaceae | 
| Genus: | Castilleja | 
| Species: | C. exserta  | 
| Binomial name | |
| Castilleja exserta (Heller) Chuang & Heckard  | |
Castilleja exserta (formerly Orthocarpus purpurascens) is a species of plant in the genus Castilleja which includes the Indian paintbrushes. Its common names include purple owl's clover, escobita, and exserted Indian paintbrush.[2]
This species is native to the Southwestern United States in various habitats of California, Arizona, and New Mexico; and to Northwestern Mexico.[3] It is an introduced species in Hawaii.
Description

Castilleja exserta is an annual herb about 100–450 millimetres (4–18 in) tall with a hairy stem covered in thready leaves. Like other related Castilleja plants, this species is a hemiparasite, deriving some of its nutrients directly from the roots of other plants by infiltrating them with haustoria. As a result, its own leaves are small and reduced.
Although this species is variable in appearance and easily hybridizes with other Castilleja species, it generally bears a brightly colored inflorescence of shaggy pink-purple or lavender flowers. The thin, erect bracts are usually tipped with the same color, giving the inflorescence the appearance of a paintbrush.[4]
Varieties
Varieties include:
Bay checkerspot butterfly host
This is a crucial host plant for the Bay checkerspot butterfly (Euphydryas editha bayensis), which is a threatened species that is endemic to the San Francisco Bay region in California.
The seeds were harvested by indigenous peoples of California for food.[12]

2015
Antelope Valley Purple owl's clover
References
- ↑ "NatureServe Explorer 2.0". explorer.natureserve.org. Retrieved 16 April 2023.
 - ↑ CalFlora database: Castilleja exserta . accessed 3.23.2013
 - ↑ Sullivan, Steven. K. (2018). "Castilleja exserta". Wildflower Search. Retrieved 2018-07-06.
 - ↑ "Castilleja exserta". in Jepson Flora Project (eds.) Jepson eFlora. Jepson Herbarium; University of California, Berkeley. 2018. Retrieved 2018-07-06.
 - ↑ CalFlora: Castilleja exserta ssp. exserta
 - 1 2 3 "Castilleja exserta (A.Heller) T.I.Chuang & Heckard | Plants of the World Online | Kew Science". Plants of the World Online. Retrieved 2021-07-19.
 - ↑ CalFlora: Castilleja exserta ssp. latifolia
 - ↑ "Castilleja exserta var. latifolia (S.Watson) J.M.Egger | Plants of the World Online | Kew Science". Plants of the World Online. Retrieved 2021-07-19.
 - ↑ CalFlora: Castilleja exserta ssp. venusta
 - ↑ USDA: C. e. ssp. venusta
 - ↑ "Castilleja exserta var. venusta (A.Heller) J.M.Egger | Plants of the World Online | Kew Science". Plants of the World Online. Retrieved 2021-07-19.
 - ↑ Lady Bird Johnson Wildflower Center Native Plant Information Network (NPIN) — Castilleja exserta (Purple owl's clover) . accessed 3.23.2013
 
External links
 Media related to Castilleja exserta at Wikimedia Commons- Closeup photos — at Henry Coe State Park, S.F. Bay Area.
 - Castilleja exserta — U.C. Photo gallery
 

