SafePlants

Bryum: A World of Moss

Bryum is a diverse genus of mosses belonging to the family Bryaceae, encompassing over a thousand described species. This makes it potentially the largest genus of mosses in the world.

Considerations for Pets

• Bryum mosses, when dry, can have corkscrew-like shoots with leaves spirally twisted around the stem, potentially posing a minor ingestion hazard if your pet attempts to eat them.

Scientific Classification

• Genus: Bryum
• Family: Bryaceae

Common Names

• Dixon's Thread-moss (for Bryum dixonii)
• Capillary Thread-moss (for Bryum capillare)
• Silvergreen bryum moss, Silver-moss (for Bryum argenteum)
• Red thread-moss, Glossy red bryum moss (for Bryum miniatum)

Synonyms and Related Taxa

• Bryum roseum (formerly for Rhodobryum roseum)
• Rosulabryum capillare is associated with Bryum capillare

Distribution and Habitat

• Bryum dixonii is endemic to Scotland, found in montane habitats.
• Bryum argenteum is a cosmopolitan moss.
• Bryum capillare was observed overlooking Alum Creek in Delaware, Ohio.
• Baltic bryum grows on grazed salt marshes in the Netherlands, but is listed as susceptible on the Red List of Dutch mosses.

Morphological Characteristics

• Bryum argenteum forms very close tufts or cushions. It occurs in patches or as scattered individuals mixed with other mosses. They appear as pale green or almost white, compact tufts or patches which look shiny and silvery grey.
• Bryum moss generally appears as tufts or patches of finely textured plants.
• Bryum capillare grows in tufts or patches, with stems mostly 1 to 3 cm tall. Dry plants usually have corkscrew-like shoots, with leaves spirally twisted around the stem.
• Bryum flaccidum grows with its leaves arranged in a rosulate form.

Ecological Role

• Bryum argenteum is an important component of the Biological Soil Crusts (BSCs) found in the Gurbantunggut desert.
• Bryum caespiticium is also known as sidewalk moss.

Genetic Information

• RAPD (Random Amplified Polymorphic DNA) techniques have been used to assess the level of genetic diversity in Bryum pseudotriquetrum.

Interactions with Other Organisms

• Epiphytic bacteria provide freezing protection in the Antarctic moss, Bryum argenteum.
• Waitea circinata is a fungal pathogen that can affect turfgrasses where Bryum argenteum is present.

Quirky Facts

• Bryum argenteum spores are yellow and have many oil droplets.

Further Information

• Jepson eFlora for CA Vascular Plants: California Moss eFlora
• Discover Life: Bryum argenteum - Silvergreen bryum moss
• Encyclopedia of Life: Search Encyclopedia of Life for Bryum argenteum.
• AusMoss: Bryum Hedw. Bryum Moss.