Dendroalsia abietina (Hooker) E. Britton
Dendroalsia abietina is a very large (10-15 cm), pleurocarpous moss, with sturdy stems and regularly pinnate branches, found on large boulders, rock walls and tree trunks, typically in partial shade. When moist, plants are bright green and soft, splaying out from the substrate like fern fronds. When dry, plants are dark green-brown and stiff, with branches folding in and stems curling in a highly characteristic fiddlehead manner. Its leaves are arranged in five distinct rows, giving the branches a quite organized, coniferous look, particularly when barely moist.
Scroll down for more photos (click to enlarge) and descriptions of habitat, male and female plants, leaves, sporophytes, distribution map, name origin, and similar species.
Habitat: Dendroalsia abietina can be found on large boulders, rock walls, and tree trunks and branches, often covering large swaths, typically in partial shade.
Habit: Dendroalisa abietina has fern-like pinnately branched secondary fronds, which grow along a prostrate primary stem hidden beneath. When dry, the branches fold in and the stems curl under like stiff, wiry fiddleheads. The fronds open when moist, and dangle horizontally or downward, softer but still quite sturdy.
Plants: Dendroalisa abietina plants are very large (10-15 cm), have thick, sturdy stems and regularly pinnate branches.
Leaves: Dendroalsia abietina leaves spread from the stem when moist in 5 distinct rows, and overlap neatly and tightly against the stem when dry. Stem leaves are larger (2.5-3.6 mm long) than branch leaves (1.6-2.2 mm long) but both are ovate-lanceolate, and taper toward a relatively blunt, toothy tip, and have margins that are recurved near the base. Near the leaf tip, the midrib (costa) has many coarse teeth, and the mid-leaf (laminal) cells overlap slightly forming little bumps (i.e. are prorate). The stems are covered with many branched paraphyllia, which can be more easily seen if a few leaves are removed.
Sporophytes: Dendroalsia abietina sporophytes are on the underside of female plants, on branches very close to the stem. Capsules are atop short (2 mm) setae.
Perigonia: Dendroalsia abietina is dioicous, with separate male and female plants. Perigonia, the male organs, appear as tiny onions (2 mm) on the underside of the male plants, near the stem. Each perigonium contains many sausage-shaped antheridia, each containing thousands of sperm.
Distribution: Dendroalsia abietina is found along the west coast of North America. It is common throughout California, and is relatively common in Santa Barbara County.
Name: The genus name Dendroalsia means tree-like (dendron is Greek for tree) Alsia, another similar genus. The species name presumably means ‘little fir,’ referring to the fir-like appearance of the branches.
Similar Species in Santa Barbara County
Beginners may confuse Dendroalsia abietina with Bestia longipes, another large moss with regularly pinnate branches. Bestia longipes is restricted to rock faces in canyons along the immediate coast of California, and has more delicate leaves and softer, more pliable branches and stems which do not curl under as significantly when dry.
Bryophytes of Santa Barbara 