Montana Field Guide

Stems 20–60 cm. Leaves oblong to oblanceolate, 6–20 cm long. Inflorescence of well-separated flowers, 6–25 cm long; bracts 2–6 mm long. Flowers yellowish-green; sepals 2–4 mm long; lip petal 2–3 mm long; spur clavate, 3–4 mm long. Capsule 5–8 mm long (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).

Alaska Rein Orchid - Piperia unalascensis
*Inflorescence: Flowers are well-separated. Flowers do not spiral on the stalk.
*Flowers: Petals and sepals are yellow-greenish.
*Lip petal: Has a short spur, clavate (club-shaped), 3-5 mm long. The spur is about as long as the lip petal.
*Leaves: Prostrate, but not appressed to the ground. Often withering by the time pollination occurs.

Dense Flower Rein Orchid - Piperia elongata, SOC
*Inflorescence: Flowers are sparse to dense, tending to overlap yet not be crowded. Flowers do not spiral on the stalk.
*Flowers: Petals and sepals are yellow-green to green.
*Lip petal: Has a long, slender spur, weakly curved spur, 6-15 mm long. The spur is more than twice as long as the lip petal.
*Leaves: Prostrate, but not appressed to the ground. Often withering by the time pollination occurs.

Hillside Rein Orchid - Piperia elegans
*Inflorescence: Flowers are crowded. Flowers do not spiral on the stalk.
*Flowers: Petals are white with green sepals.
*Lip petal: Has a long, slender spur, weakly curved spur, 8-12 mm long. The spur is more than twice as long as the lip petal.
*Leaves: Prostrate, but not appressed to the ground. Often withering by the time pollination occurs.

Bog Orchids - Platanthera species
*Flowers: Arranged in a spike-like raceme, but do not spiral around the stalk.
*Lip petal: Forms a downward pointing spur.
*Leaves: Either near the plant's base (basal) or leafy along entire stem (cauline). If basal then either appressed to the ground or only on the lower stem (lacking upper stem leaves). If cauline then leaves are sheathing, alternately-arranged, and may whither by the time pollination occurs.

Ladies'-tresses - Spiranthes species
*Flowers: Arranged in a spike and spiral on the stalk to form 3- or 4- ranks/columns.
*Lip petal: Lacks a spur.
*Leaves: Relatively long and narrow. Largest at the base, becoming progressively smaller towards the inflorescence. Leaves usually do not whither by the time pollination occurs.

Moist to more often dry forest, thickets, stream banks; valleys, montane (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).