Castilleja was scientifically described by Carl Linnaeus the Younger using a partial description by José Celestino Bruno Mutis in 1782.

[3][1] However, Nutttall's Euchroma grandiflora had already been named and correctly placed as Castilleja sessiliflora by Frederick Traugott Pursh in 1813.

Mutis wrote in Latin, "Ab Stemodia quantum ex characteríbus video, valde diversa haec singularissimeplanta, proculdubio numeranda ínter Didynamas.

The genus includes many species that are completely herbaceous, lacking woody material in their above-ground parts.

[9][10] Pollinators aid these plants in reproduction, with insects visiting the flowers, as well as hummingbirds for some species.

[11] Castilleja species can play an important role in plant community dynamics and multitrophic interactions.

[13][14][15] This hybridization potential has been identified as a threat to the genetic integrity of certain endangered Castilleja species.