About this fungus
Spring Rollrim is a fungus in the Paxillaceae family. Its habitat and field characteristics are summarised below.
A brown, depressed rollrim under northern aspen or birch, with a strongly inrolled young margin and gills that darken where pressed.
What to check
Record the living host, cap texture, detachable decurrent gills, flesh staining and spore deposit. Microscopy and regional keys are needed for species confidence.
Variation
Cap colour ranges from yellow-brown to reddish or olive-brown and becomes more depressed with age. Weather can make the surface sticky or dull.
Lookalikes
Paxillus involutus and allied North American taxa are extremely similar. Host and geography help but do not replace microscopic work.
Habitat and range
A boreal and montane North American species associated especially with quaking aspen and paper birch, fruiting mainly in late summer and autumn despite its common name.
Food safety
Poisonous.