R. Fraley

Feather Moss (*Hypnum curvifolium*)

Hypnum curvifolium

Feather Moss on Decaying Wood
Feather Moss on Decaying Wood
Fine, shingled leaves sweep together in soft, featherlike mats, capturing ambient moisture beneath the forest canopy.
This stacked composite highlights the delicate, secund leaf arrangement of Hypnum curvifolium, a species known for its fine texture and tightly layered fronds. • Size: 534×800

Camera: Canon EOS 5D Mk IV
Lens: EF100mm f/2.8L Macro IS USM
Settings: ISO 1600 • Aperture f/5.0 • Shutter 1/250 s

Description

Feather Moss (Hypnum curvifolium) forms dense, low mats across logs, stumps, and shaded forest soil. Its shoots lie flattened against the substrate, with leaves that sweep distinctly to one side—a trait known as secund curvature, and a signature characteristic of this species.

Key identifying features include:

  • Fronds: Fine, slender, and flattened, creating a soft, lace-like layer.
  • Leaves: Overlapping like shingles, narrow and curved in a single direction.
  • Color: Yellow-green to bright green when moist; slightly muted when dry.
  • Growth habit: Creeping and mat-forming, tightly adhering to wood or soil.

H. curvifolium is noticeably finer and more compact than the broader, taller fronds of Hypnum imponens.

Habitat

Feather Moss Habitat on Forest Floor
Feather Moss Habitat on Forest Floor
A thriving colony on a decaying log, taking advantage of filtered light and constant humidity.
This species excels in cool, shaded microhabitats, especially on rotting hardwoods and the north-facing sides of logs. • Size: 4480×6720

Camera: Canon EOS 5D Mk IV
Lens: EF100mm f/2.8L Macro IS USM
Settings: ISO 1600 • Aperture f/5.0 • Shutter 1/250 s

Growth Detail

Feather Moss Close Study
Feather Moss Close Study
Fine, secund leaves sweep together in tight, shingled layers characteristic of *Hypnum curvifolium*.
This view highlights the species’ delicate architecture and its close adherence to decaying wood. • Size: 6664×4444
Camera: Canon EOS 5D Mk IV
Lens: EF100mm f/2.8L Macro IS USM
Settings: ISO 6400 • Aperture f/13.0 • Shutter 1/13 s

Sporophytes Close Study

Feather Moss Sporophytes Close Study
Feather Moss Sporophytes
Short, slender sporophytes emerge sparsely from the fine mat of *H. curvifolium*, revealing the colony’s reproductive stage.
The sporophytes are fewer and shorter than those of H. imponens, accentuating a key difference between the two species. • Size: 4480×6720
Camera: Canon EOS 5D Mk IV
Lens: EF100mm f/2.8L Macro IS USM
Settings: ISO 1600 • Aperture f/5.0 • Shutter 1/250 s

Ecological Role

Feather Moss contributes significantly to forest-floor dynamics:

  • Retains moisture in decaying wood and soil.
  • Provides microhabitats for small invertebrates and fungi.
  • Stabilizes organic matter, slowing erosion and aiding decomposition.
  • Supports seedling establishment by maintaining humidity around germinating plants.

Though delicate in appearance, its ecological importance is profound.

For a comparison with a larger, broader species in the same genus:

Even in the dimmest forest light, Feather Moss weaves a soft green foundation across fallen wood.