Montana Field Guide

Stem 10–35 cm. Leaf blade 5–18 mm wide. Bracts 2 or more, 1–5 cm long. Flowers 1 to 3; sepals 15–25 mm long; petals white, drying yellowish with serrulate margins; inner surface often yellow basally, hairy with a small, dark circular gland near the base; anthers lanceolate, apiculate. Capsule nodding, ovoid 1–3 mm long (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).

Baker Mariposa Lily - Calochortus apiculatus
*Basal Leaf: Flat, broader and usually more than half as long as the stem leaves.
*Anthers: Lanceolate (wider from base to below middle and tapering to the tip) and apiculate (short, sharp tip).
*Sepals: 15-25 mm long.
*Petals: Outside is white, drying yellowish, and serrulate on the margins. Inside the petals are hairy (or strongly bearded), white, and at the base it is yellow with a small (1.5 mm), circular, dark, central gland.

Elegant Mariposa Lily - Calochortus elegans
*Basal Leaf: Flat, broader and usually more than half as long as the stem leaves.
*Sepals: purplish, 10-15 mm long.
*Anthers: Lanceolate (wider from base to below middle and tapering to the tip) and apiculate (short, sharp tip).
*Petals: Strongly clawed. Outside is white. Inside is purple, surface is hairy (ciliate or densely long bearded), and at the base is darker purple crescent-shaped gland.

Big-pod Mariposa Lily - Calochortus eurycarpus
*Basal Leaf: Flat, broader and usually more than half as long as the stem leaves.
*Anthers: Oblong and blunt at the tip.
*Sepals: yellowish, 15-30 mm long.
*Petals: Outside is white or purplish, 3-4 cm long. Inside is purplish with sparse hairs and at the base a fringed yellow gland; centrally there is a large circular purplish spot.

The following Mariposa Lilies differ from those above in that their basal leaves are channeled (v-shaped), similar in width to the stem leaves, and often less than half the length of the stem leaves:

Gunnison's Mariposa Lily - Calochortus gunnisonii
Bruneau Mariposa Lily - Calochortus bruneaunis, SOC
Nuttall's Mariposa Lily - Calochortus nuttallii
Green-band Mariposa Lily - Calochortus macrocarpus

Grasslands, drier meadows, forest openings; valleys to lower subalpine (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).