Montana Field Guide

PLANTS: A short, hemi-parasitic, herbaceous, perennial forb that arises from a branched caudex. Plants are many-stemmed, generally decumbent at their bases, erect upwards, and 10-30 cm tall; stems occasionally branch above. Foliage is covered with short to long and soft hairs which often point downwards; hairs are seldom matted or tangled.

LEAVES: Arranged alternately on the stem. Alternately arranged, narrow, the lower leaves tending to be entire, while the mid- to upper-leaves often have two pairs of long narrow lateral lobes.

INFLORESCENCE: A dense, terminal, bracteate spike. Each flower is subtended by a broad leaf-like bract with yellowish or sometimes purplish tips and 1-3 pairs of slender lobes. The tubular calyx, 10-20 mm long, surrounds the corolla and is cleft into 4 equal, pointed lobes. The yellow, tubular corolla, 15-20 mm long, tapers to a short hood (galea) above and 3 small lobes below. Although the flowers are not completely hidden, the inflorescence takes its color from the bracts rather than the flowers.

Taxonomy
Castilleja pilosa var. longispica is treated at the species level as Castilleja longispica in Manual of Montana Vascular Plants (Lesica et al. 2012). The Intermountain Flora (1984) treated the plant at the variety level. In deference to Noel Holmgren the Flora of North America-Volume 17 (2019) treats the plant at the variety level though species recognition may be justified (Mark Egger personal communication).

Sources: Giblin et al. [eds.] 2018; Lesica et al. (2012); Holmgren in Intermountain Flora 1984.

Flowering in June, July and early August.

Castilleja is a difficult genus because hybridization and allopolyploid speciation (containment of multiple sets of chromosomes that are derived from different species) fuzz a species’ characteristics (Giblin et al. [eds.] 2018).

To identify Castilleja species, it is important to (Giblin et al. [eds.] 2018):
* note colors of the bract, calyx, and corolla while in the field, and
* press many bracts, calyces, and corollas separately to show their shapes.

Parrot-head Indian Paintbrush - Castilleja pilosa var. longispica, native:
* Bracts are green to yellow or purplish.
* Upper third of the stem with green, lobed leaves.
* Lobes of the calyx are cleft to about the same length.
* Inflorescence with puberulent to sparsely villous hairs.
* Montana plants occur in montane to subalpine zones.

Pallid Indian Paintbrush - Castilleja pallescens, native:
* Bracts are green to yellow or purple-tipped. Calyx is yellow.
* Upper third of the stem with green, often with linear lobed leaves, or at least the central lobe is linear.
* Lobes of the calyx are cleft more deeply in front and back than compared to the sides.
* Ultimate calyx lobes are acute to acuminate.
* Galea is 2-4 mm. Lower corolla lip is 2-3 mm. Thus, lower lip is more than half the length of the galea.
* Inflorescence with puberulent to pilose hairs.
* Montana plants occur in valleys to alpine zones.

Snow Indian Paintbrush - Castilleja nivea, native:
* Bracts are yellow to purple-tipped and woolly-villous.
* Upper third of the stem with green, lobed leaves.
* Lobes of the calyx are cleft to about the same length.
* Inflorescence villous-tomentose.
* Montana plants occur in the alpine zone (turf and fellfields).

Sagebrush steppe, grasslands, and woodlands in the montane zones of Montana (Lesica et al. 2012).

POLLINATORS
The following animal species have been reported as pollinators of this plant species or its genus where their geographic ranges overlap: Bombus appositus, Bombus bifarius, Bombus fervidus, Bombus flavifrons, Bombus melanopygus, Bombus sylvicola, Bombus occidentalis, and Bombus kirbiellus (Macior 1974, Thorp et al. 1983, Bauer 1983, Mayer et al. 2000, Wilson et al. 2010, Pyke et al. 2012, Koch et al. 2012, Miller-Struttmann and Galen 2014, Williams et al. 2014).