(1858)[2] Bryoria fremontii is a dark brown, horsehair lichen that grows hanging from trees in western North America, and northern Europe and Asia.

The simplest characteristic that distinguishes it from the other species of Bryoria is that its main branches grow to be quite thick (greater than 0.4 mm wide), and usually become somewhat flattened, twisted, and wrinkled in older specimens.

[3] This species is common in the mountainous areas of western North America, being found throughout most of the interior of British Columbia (less common or absent in the northern third of the province), extending east into the Alberta Rockies, and south into Montana, Idaho, and Wyoming, as well as being found in Washington, Oregon, and California.

[3] In general, most species of Bryoria prefer drier forests with more open canopies than do the other genera of arboreal hair lichens (like Alectoria, Usnea, and Ramalina).

Researchers have documented up to 3291 kg of arboreal hair lichens (of which this species was a major constituent) per hectare in some areas in the interior of British Columbia.

[3] Bryoria fremontii (along with many other lichens) is significant food source for a variety of different species of ungulates and rodents.

Nonetheless, this lichen was, and still is, highly regarded as a food for Salish peoples,[3][5][25] such as the Secwepemc,[6] the Shuswap,[26][27] the Nlaka'pamux,[28] the Lillooet,[29] and the Sinkaietk[30] There is a report that among the Flathead of Montana, even the smallest family would harvest over 10 kg of it every July.

[3][31] The collected specimen is cleaned by hand to remove twigs, dirt, other lichens, sap and other contaminants.

This process of cleaning is called kálka in the Secwepemc language, and may help to remove the vulpinic acid, which is slightly water-soluble.

Then a thick layer of wet vegetation (moss, fern fronds, skunk cabbage leaves, bark, grass or conifer needles) is used to cover the rocks and line the pit.

Often a barrier of large leaves, bark, reed mats, or burlap sacks is placed on top of all the vegetation to stop any detritus from falling into the food.

This is accomplished by holding a large stick upright in the pit as it is being filled with the dirt, vegetation, and food.

This stick is pulled out after the pit is completely covered, leaving a small hole that extends right down to the hot rocks at the bottom.

The Dakelh have been recorded to bake it into a kind of fruitcake: the lichen is mixed into the bread dough like one would do with raisins.

[3][34] The lichen can also be prepared using more modern cooking methods such as pressure cookers, crockpots or clay bakers.

[45] Several different First Peoples in British Columbia (including the St'at'imc[46] and the Nlaka'pmx[28]) traditionally made clothing out of it.

Lichen garments were usually only worn by poorer people,[28] as they quickly absorb water and are unsuitable in wet weather.

[6] The garments were made by twisting together ropes and weaving them together with plant fibre to form vests, ponchos, shoes and leggings.

Various First Peoples in British Columbia traditionally mixed these lichens with mud for chinking cracks in houses, as well as using them as liners for moccasins and diapers, and as a predecessor to paper towels for a variety of domestic purposes.

[48] Some Okanagan people claim that neither men[34] nor menstruating women should come near a pit cook when the lichen is cooking, or it will turn out badly, and there is a Nlaka’pmx belief that a bereaved spouse should not eat lichen cake for a full year after the death of their partner.

Not realizing that the swans are just faking, Coyote ties them to his son and crawls up a pine tree to get a pitch top for kindling.

The swans then flew away with his son, and in Coyote's haste to get down to save him his long hair got caught in the tree.

Furthermore, in certain areas Bryoria fremontii can contain toxic quantities of vulpinic acid, which is one of the most potent poisons found in lichens.