Twisted Oak Moss (Syntrichia laevipila)

Resources

• BC Species and Ecosystems Explorer Entry
• Garry Oak Ecosystems Recovery Team Factsheet
• Biodiversity Galiano iNaturalist Observations

Status

• BC: Blue – S3 (2015)
• COSEWIC: Special Concern
• SARA: Special Concern (2005)
• Global: Not ranked
• Galiano Island Status: Confirmed

Description

Twisted oak moss is a small moss species that grows in clumps on tree bark, primarily oak bark. This species is easily recognized by its tiny size (the stems are no longer than 5 mm). However, the main stems occasionally protrude from the plant. The leaves, which are generally shaped like spatulas, rounded at both ends, and end in bristle-like appendages (awns). In Canada, they rarely measure more than 2 mm. When dry, they are twisted and, when wet, they spread somewhat and curl slightly.

Habitat

Twisted oak moss only grows on tree bark, particularly on the bark of the Garry oak. Although it is commonly found on tree trunks, it can also be found at the base and on the upper branches. The majority of the populations occur on trees in open habitats where the summers are dry and the temperature is mild to very hot, and the winters are humid and the temperature is cool to cold. Twisted oak moss rarely grows in combination with other mosses or lichens.

Range

Twisted oak moss occurs, albeit sporadically, all around the world. This species can be found in Southern South America, Europe, Asia, North Africa and Western North America. In North America, it occurs along the coast of British Columbia, and further inland in the state of Washington, Oregon and California. In Canada, twisted oak moss occurs only along the coast of British Columbia, more specifically in the Garry oak habitats on Vancouver Island, from the southern tip of the island to the Nanaimo area.

Threats

The main threat to the twisted oak moss is the disappearance of old Garry oaks, which would lead to the eradication of most twisted oak moss populations in Canada. However, the absence of young Garry oaks to replace older trees poses a greater threat to this species; on many private properties, oak shoots are often removed or they are grazed by feral sheep and goats, as well as mule deer.

Galiano Status

Populations have been documented on Mount Sutil, Mount Galiano, and at Bluffs Park.