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]
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]