Montana Field Guide

Plant: Acrocarpous (Vitt 1988). Small to robust, erect moss growing in loose tufts or extensive patches. Gray-green to blue-green, but becoming red-brown with age. Stems (1-)4-5(-10) cm tall, simple, and with brown tomentum only at the base.

Leaf: When dry, leaves imbricate, mostly erect, and almost straight. When moist, erect spreading to widely spreading. Lanceolate to linear-lanceolate leaf (3-8 mm long) from a sheathing base. Leaf is slender and shiny with infolded margins. Sheath is oblong-rectangular, yellowish, and tapers to the leaf. Costa is excurrent as a red awn, somewhat toothed, and is made of lamellae.

Leaf Cells: Teeth consist of 3 cells (1 large cell above & 1-2 small cells below). Sheath: Cells are narrowly rectangular, 4-6:1. X-S: Marginal laminae are of 1 layer and 5-7 cells long, transparent, and overlap to cover some of the lamellae; in X-S cells are smooth or slightly crenulate. In top view marginal laminae are elongate with thick walls. Lamellae X-S: 20+, each 6-8 cells high, with the uppermost cell ovate to pyriform, thick-walled, ending with a distinct knob, and smooth (or rarely faintly papillose). The uppermost cell of each lamella that occurs under the overlapping lamina is ovoid and less strongly thickened.

P. juniperinum usually grows in drier habitats than P. strictum. The former also has stems covered with dense brown rhizoids near its base whereas P. strictum has a white wooly stem (FNA 2007).

P. juniperinum has reddish awns rather than entirely hyaline awns as in the similar P. piliferum. The former is also larger and grows in somewhat moister habitats (FNA 2007).

Exposed, well-drained soils, usually acid soils. In old fields, openings in forest, along trails and roadcuts, on thin soil over rock, and on open ridges. Rarely in moist or wet places. Low to high elevations.

Dioicous. Male plants with an abrupt transition to a spicate fertile portion.

Seta is 1-5 mm tall, stout, yellow to red-brown. Capsule is 2.5-5 mm long, longer than wide (1.5-2:1), dark-brown to red-brown, glaucous when fresh, becoming horizontal at maturity. Several sporophytes to a plant, but one seta to a perichaetium. Calyptra covers the capsule, is of densely interwoven hairs or felt, and white to light brown.