Alectoria imshaugii (aka Spiny Witch’s Hair)
Range: Southern British Columbia to California, east to western montana; common in low to mid elevation forests with Cont Div.
Substrate: Bark & wood of both conifers & hardwoods.
Habitat: Common in moist low to mid elevation forests e Cas, but only west Cascades. On exposed pines & other conifers.
Sensitive to air pollution.
Description: Tufted or shrubby, erect or subpendent (somewhat drooping), usually 5-8 cm long, produces isidia from fissures in the cortex that often originate from old pseudocyphellae; occasionally with an almost translucent appearance; branches with clusters of isidia-like spinules; pseudocyphellae elongate, slightly paler than the surrounding cortex; apothecia rare.
Color: pale greenish yellow (or tinged blue-black when dying or in exposed sites)
Chemistry: Cortex & medulla PD+ orange, K+ yellow, KC-, C-, rarely KC+R, P- or P+ yellow or orange. (thamnolic acid), or PD-, K-, KC-, C- (squamatic acid).
Lookalikes: In general aspect, resembles some shrubby usnea species, but lacking an axis (central white cord). Easily distinguished from other local species of Alectoria by its clusters of isidia-like spinules. It is the only Alectoria with isidia or thamnolic, & squamatic acid.
Bibliography: Macrolichens of the Pacific Northwest, by Bruce McCune & Linda Geiser, Lichens of North America, by Brodo, Sharnoff, & Sharnoff
Database Entry: Distance Everheart 12-26-13