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Summer 2021


Parasitic and saprobic; growing, usually on the base, of hardwoods both alive and dead.This species can be found growing from the summer through the fall in Africa, Asia, Europe and North America. It causes butt rot in the heartwood of the host tree which will eventually cause the wood to to hollow out. The fruiting body of this polypore varies from 25-80 cm across and is composed of one to five individual fronds that narrow at the base. While this species doesn’t have a proper cap and stem, it has branching bodies that meet at its base. Each frond is approximately 6-25 cm wide, irregular or kidney shaped, slightly convex, or flat. It is dry, velvety, and often radially wrinkled or having zones of different colors or textures. They are off-white to tan and do not bruise when damaged. This species’ base is 4-10 cm long, 3-6 cm wide, off-center or centered, and yellowish to light brown in color. Like the fronds, its base is dry, slightly velvety, tough and not bruising. This species has pores that run down the psedostipe, are whitish, not bruising, visible to the eye, angular, 0.5-2 mm across, and have tubes that are approximately one cm deep. This species also has a white spore print and turns yellow to red with KOH. Recently, Bondarzewia berkeleyi was found to contain a partitivirus and a mymonavirus, a novel discovery and the first to be described in this genus (Vainio and Sutela 2020). Additional research on this species is needed to future understand the viruses it hosts. A study done in 2014 proved that this species and Merulius eurocephalus have morphological dissimilarities and are not the same species as was once thought (Kumar and Harsh 2014). Note: This mushroom is very large and realtively uncommon so it was not harvested and cannot be found in this herbarium. ID number:


Location: East Brook Valley, Walton, NY (BC - Betula Creek)

Bondarzewia berkeleyi