Berkeley’s Polypore: The Old Oak’s Bounty

What are the benefits of Berkeley’s Polypore?

The benefits of Berkeley’s Polypore (Bondarzewia berkelyi) are:

  • an abundant source of food
  • a healthy alternative to ground meat
  • in possession of potent antioxidant effects, similar to Reishi Mushrooms
  • a source of an intense yellow fungal dye

Bondarzewia berkeleyi is a member of a genus belonging to the order of Russalales, consisting of poroid (having pore-like holes) basidiocarps (fungi that produces basidia – a type of spore). In North America B. berkeleyi is joined by it’s cousin Bondarzewia mesenterica as being the most common species in this genus (Chen et al, 697). It is also reported in the Guizhou Province and Guanxi Autonomous Region of China, where it is called Dà mógū (大蘑菇) or ‘Big Mushroom’ by the native populations there (Yucheng and Xingliang, Abstract). Berkeley’s Polypore is also sometimes referred to as Stump Blossom after its habit of only forming at the base of trees or on tree stumps. It was first described by Western mycology in the work of the Swedish mycologist Elias Magnus Fries in the 1851 (iNaturalist, 2020). A child prodigy who began collecting and studying fungi at the age of 12 in 1806. Fries has been described as the Linnaeus of Mycology. The fungi is named after the British cryptogamist (cryptogams are plants that reproduce by spore) and mycologist Miles James Berkeley, a contemporary of Fries.

Berkeley’s Polypore arrives as thick, knobby fingers that exude latex if cut. Gary Lincoff has described it as a huge hand reaching out of the ground (Emberger, 2008). From the Stump Blossom’s hand unfurl rosettes or clusters of creamy caps, almost always on the ground near the base of trees. Sometimes it can be found in seeming isolation from trees, but upon investigation there is typically a large root or a long buried tree stump beneath the surface. Stump Blossoms are easy to cut away when young, and indeed, that is the only time this fungi should be eaten (Missouri Department of Conservation, 2020). When foraging for Berkeley’s Polypore, the intrepid mycologist will look for Prunus pensylvanica (Bird Cherry), Quercus alba (White Oak), Quercus coccinea (Scarlet Oak), Quercus falcata (Spanish Oak), Quercus prinus (Chestnut Oak), or Quercus velutina (Black Oak) (Grand and Vernia, 2-3), as well as various conifers (Essien et al, 65). It does good work at parasitizing and digesting trees, but it does so slowly as to not kill its host for many years. It’s mycelia can be found rotting tree roots and specifically the trunks of tree with a stringy white rot. The decayed wood takes on a strong odor of anise when cut and will maintain the scent for many months afterwards (Luley et al, 2020).

In the few lab studies that have been done, B. berkeleyi has been found to produce similar anti-oxidative properties as Reishi, albeit in smaller amounts (Essien et al, 65). When the mycelia mass of Berkeley’s Polypore is treated with an aqueous solution of the caustic agent Potassium Hydroxide (KOH) – also known as lye – an intense yellow color is produced. This reaction could mark B. berkeleyi as a source for unique fungal dyes (Liu, 101).

Cultivation of Berkeley’s Polypore is simple in materials, but likely time intensive. Beginning with a live liquid culture of Bondarzewi berkeleyi, an all-in-one wood based grow bag should suffice for beginning indoor cultivation. As has been mentioned, the colonization process is slow in nature and one should expect the same pace when purposefully cultivating this large polypore. If possible, once cultures are started in the sterile grow bag, transferring to a medium of oak sawdust or chips could result in higher yeilds. Another method is to inoculate wooden dowels and find a suitable stump to colonize with the fungus. In this way, while at subject to weather for growth, you will be able to enjoy harvests of Stump Blossoms for many years to come. In this way, while at subject to weather for growth, you will be able to enjoy harvests of Stump Blossoms for many years to come.

Whenever there is a known edible mushroom that produces a large degree of flesh, there are discussions of how to use it as a food source. When relatively young and tender, cut portions of Berkeley’s Polypore will smell like freshly baked bread. If eaten raw, or slightly cooked, Stump Blossoms maintain the characteristic radish-like spiciness of their cousins, the russalas. They soak up a marinade readily, and once so treated, can be braised for up to four hours for a meaty component to your meal (Mushroom Horticulture, 2020). It pairs well with ginger, cloves, black peppercorns, blackberries, white rice vinegar, tamari, and honey. Often, due to it’s role as a copious producer, this mycoform has been substituted for ground meat flavored with dill, mint, garlic and pepper and served with zucchini (Brill, 2020).

Mushroom Images

Bondarzewia berkeleyi Cover from wintersbefore
Bondarzewia berkeleyi 1 from Nonpast


  1. Brill S (2020) Mushroom Recipes Mostly From The Wild Vegan Cookbook. Retreived from
  2. Chen J J, He S H, Cul B K, and Cooper J A (2016) Molecular phylogeny and global diversity of the remarkable genus Bondarzewia (Basidiomycota, Russulales) Mycologia (108, 4) pp 697-708
  3. Emberger G (2008) Bondarzewia berkeleyi. Retrieved from
  4. Essien E E, Udoh B I, Peter N S (2015) In vitro Antioxidant Activity and Total Polyphenols Content of Wild Edible Polypore Mushrooms – Bondazewia berkeleyi and Ganoderma lucidm. Britich Journal of Pharmaceutical Research (6,1) pp 61-67
  5. Grand L F and Vernia C S (2007) Biogeography and hosts of poroid wood decay fungi in North Carolina: Species of Abortiporus, Bondarzewia, Grifolo, Heterobasidion, Laetiporus, and Meripilus. Mycotaxon. (99, 99-102) pp 1-7
  6. iNaturalist (2020) Berkeley’s Polypore. Retrieved from
  7. Liu J (2007) Secondary metabolites from higher fungi in China and their biological activity. Drug discoveries & therapeutics. (1,2) pp 94-103
  8. Luley C J, Emberger G, and Burdsall H (2020) Bondarzewia berkeleyi. Wood Decay Fungi of Living Trees. Retrieved from
  9. Missouri Department of Conservation (2020) Berkeley’s Polypore: Bondarzewia berkeleyi. Retrieved from
  10. Mushroom Horticulture (2020) Berkeley’s Polypore: Culinary Properties. Retrieved from
  11. Yucheng D and Xingliang W (2003) A New Edible Polypore – Bondarzewia berkeleyi. Edible Fungi of China (23, 4)

Last modified: January 25, 2021

Leave a Reply

Your email address will not be published. Required fields are marked *