Montana Field Guide

Stems simple, erect to ascending, 1–15 cm from a simple or branched caudex clothed in old leaf bases. Basal leaves 7–30 mm long, oblanceolate to spatulate, entire. Stem leaves linear to narrowly oblanceolate. Vestiture of dense, appressed, stellate hairs. Petals 5–7 mm long. Fruit ovoid, inflated, 2–5 mm high; style 2–3.5 mm long; seeds 2 to 4 per locule; pedicels sigmoid-spreading, 4–12 mm long (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).

Spatula-leaf Bladderpod - Physaria spatulata
*Pedicles are sigmoid-spreading, 4-12 mm long - at least twice as long as the fruit (silicle).
*Fruits inflated, ovoid (not obviously 2-lobed), and 2-5 mm high. Style is more than half the length of the fruit.
*Basal leaf blades thinner than 1 mm.
*Plants grow in sandy or gravelly soil (calcareous or not) on exposed slopes and ridges in grasslands, steppe, woodlands, and fellfields in the plains, valleys, montane, and alpine zones.
*Refer to Appendix A in Pipp, Heidel, and Herman (2025).

Thick-leaf Bladderpod – Physaria pachyphylla, SOC
*Inflorescence is a subumbellate raceme.
*Fruiting pedicels curve upwards (ascend), are 3-10 mm long, and less than 2 times longer than fruit.
*Fruits inflated, narrowly elliptic to globose (not obviously appearing 2-lobed), and 3-6 mm tall. Style is 1-3 mm long, shorter than the mature fruit (silicle).
*Basal leaves have distinct petioles and blades. Basal blades are oblanceolate to orbicular in shape, nearly 1 mm thick, and cupped (not folded).
*Plants grow on white to pinkish, limestone and gypsum soils on exposed ridges and slopes in the valley zone.
*Refer to Appendix A in Pipp, Heidel, and Herman (2025).

Sandy or gravelly soil of exposed slopes, ridges in grasslands, steppe, woodlands, fellfields, more common in calcareous soil; plains, valleys to alpine (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).