Montana Field Guide

Plants: Growing in crowded clumps of erect shoots, shiny, pale- to yellow-green (FNA 2007) above, olive green to brown below (Flowers 1973). Stems 5-30 mm tall (FNA 2007), branched, possessing a central strand (Flowers 1973); rhizoids pale or russet, covering the stem with woolly matting (FNA 2007).

Leaves: Spreading to ca 45 degrees, similar in dry or moist condition (FNA 2007) or leaves more upright when dry (Lawton 1971), the majority of leaf tips falling away and missing, lance-shaped, 4-6 mm in length, 0.4 mm or less in width, cupped below, tube-like above to an acute leaf tip (when present), smooth; margins sometimes saw-toothed apically; costa extending well beyond the stem, lacking dorsal crests (FNA 2007).

Leaf Cells: Lamina of 1 layer of cells, or sometimes areas with 2 layers in the apex; walls between the cells not protruding; upper laminal cells square, short and quadrangular, the angles sometimes smoothed, not porose (FNA 2007); lower laminal cells long (Lawton 1971) and very thin to quadrangular, slightly porose (FNA 2007); alar cells distinct, reddish, strongly swollen and forming auricles (Flowers 1973), not reaching the nerve, the alar region 1 cell-layer thick; costa in X-section with guide cells in 1 row, both stereid bands absent, cells with big lumens and somewhat wider walls adjacent to the guide cells in 1 or 2 rows, the ventral and dorsal superficial layers not distinct (FNA 2007).

Fruit ripens in summer (FNA 2007).

Broken leaf tips lend a distinctive appearance to both D. tauricum and Dicranum fragilifolium, another species with fragile leaves, causing confusion where their ranges overlap. The capsules of D. fragilifolium are usually bowed; those of D. tauricum are straight. In sterile plants, check the X-section of the costa in the proximal half of the leaf. In D. fragilifolium, stereid cells occur in two narrow bands; there are none in D. tauricum (FNA 2007).

Epiphytic (Vitt 1988), often on decaying wood and bottoms of tree trunks, occasionally humus overlying stone or just humus; mostly in shaded areas (Flowers 1973). Elevation: 490-7220 feet (FNA 2007).

Dioicous. Inner perichaetial bracts enveloping the stem, slowly tapering to a subula. Seta single, ochre to yellow, 15-25 mm tall. Capsule vertical, not bowed, 1.4-2.5 mm in length, erratically creased when dry, pale brown to yellow (FNA 2007); operculum with a long, frequently tilted beak (Flowers 1973); peristome of 16 teeth, separated ca halfway down into 2 lobes (seldom 3), russet, with papillae above. Calyptra hood-like, hairless, sheltering much of the capsule, falling away easily (FNA 2007).