Birch Polypore: nature’s first-aid kit

This month marks the 30th anniversary of the discovery of Ötzi the Iceman, who emerged from his frozen tomb after 5,000 years. To mark this, we are taking a look at one of the fungi he had with him when he died: Birch Polypore (Fomitopsis betulina) aka Razor Strop Fungus and Swiss Army Knife Fungus

Ötzi the Iceman's body was discovered 30 years ago with Birch Polypore fragments
Ötzi the Iceman's body was discovered 30 years ago. Image © South Tyrol Museum of Archaeology/EURAC/Samadelli/Staschitz

When Ötzi the Iceman made his final climb up the Alpine Tisen Pass 5,300 years ago, he was wounded, sick and a hunted man. Murdered on the windswept, icy mountain, his body was naturally mummified. It emerged from the retreating glacial ice in September 1991, complete with his “tool kit” — weapons, fire-lighting equipment and first-aid — providing an unparalleled insight into the world of the Neolithic agrarian-hunter.

Ötzi was already suffering from stomach pains, heart disease, arthritis, gallstones, whipworms and a recently-wounded right hand when he was killed by an arrow to his back, which penetrated below his left shoulder and pierced an artery. On and around his body, remnants of 75 mosses and liverworts were discovered, some of which he had carried there accidentally on his clothing, others had been brought deliberately to the site (Dickson et al, 2019). Evidence from pollens suggests the iceman spent his final days ascending and descending thousands of feet of the Ötztal mountains in a state of crisis, gathering essential supplies as he went (Oeggl et al, 2007).

A reconstruction of Otzi, who had Birch Polypore and Horse Hoof Fungus on his person
A reconstruction of Ötzi the Iceman © South Tyrol Museum of Archaeology/Ochsenreiter

The beleaguered 45-year-old had fragments of Horse Hoof Fungus (Fomes fomentarius) — a tinder fungus — in his belt pouch, bogmosses, such as Sphagnum affine, which were perhaps used as an anti-septic dressing for his wounded hand, and there were also two fragments of a fruiting body of Birch Polypore (Fomitopsis betulina), pierced and strung on a leather thong. Anthropologist Luigi Carpasso (1998) was one of the first to note the anti-bacterial and anthelmintic properties of this fungus, suggesting that Ötzi had been dosing himself to combat his whipworm (Trichuris trichiura) infestation, which would have caused him abdominal pain and cyclic anaemia.

In the years that have followed the iceman’s discovery, more scientists have taken an interest in this common bracket fungus and evidence of its extraordinary properties has grown. Far from being just a worm medicine, Birch Polypore (Fomitopsis betulina) has been shown to have antibacterial, antiviral, anti-inflammatory, anticancer, neuroprotective, styptic and immuno-modulating capabilities (Pleszczyńska, 2017). The troubled Ötzi was on to something...

Birch Polypore (Fomitopsis betulina)
Birch Polypore (Fomitopsis betulina)

It would be wrong to assume that knowledge of Birch Polypore’s extensive properties was lost in time — it has maintained a long tradition of use in folk medicine. Indigenous cultures, which do not always separate medicinal and “spiritual” properties, have often associated tough, perennial bracket fungi (Birch Polypore’s fruit bodies can last up to a year) with a source of eternal strength and wisdom. In central European culture, it maintained a use as a popular fungal tea, often drunk in Russia, Hungary and Romania for its nutritional and calming properties and as an immune tonic. It also has established applications, particularly in the great mushroom-hunting country of Poland, for gastro-intestinal disorders including stomach cancers (Grienke et al, 2014).

Birch polypore has also been long-acknowledged as a styptic (anti-haemorrhagic). When cut, its smooth pore surface (hymenium) was used by barbers as a strop for finishing razors, giving it the common name of Razor Strop Fungus, but it also served multiple functions. Should the barber nick their customer’s skin, small strips could be torn off and applied as a plaster to stop bleeding, while also acting as an antiseptic. It also found use as a dried powder applied to wounds and in this capacity was additionally considered a painkiller (Grienke et al, 2014). It’s not hard to imagine how Ötzi may have seen this fungus as an essential piece of his first aid kit.

A large specimen of Birch Polypore (Fomitopsis betulina)
A large specimen of Birch Polypore (Fomitopsis betulina)

So where do the near-miraculous properties of this brown-rot fungus come from? Analysis of Birch Polypore’s fruiting bodies revealed the presence of 17 fatty acids, sugars, biomolecules with anti-oxidant properties, phenolic acids, indole compounds, sterols, and triterpenes. Polyporenic acids A and C are thought to be behind its fungicidal, anti-viral anti-inflammatory and larvicidal properties, while it gets its fungicidal properties from piptamine (which has been used to treat E coli). The polyporenic acids have also been shown to prohibit cancer cell proliferation and growth (Pleszczyńska et a., 2017). Agaric acid, meanwhile, was the active component for tackling Ötzi’s parasites.

Understanding of its pharmacological applications is an expanding field but fractions of Birch Polypore have been shown to be effective against a multitude of conditions. Mycologist and entrepreneur Paul Stamets has prepared formulations from polypores, including Fomitopsis betulina, which was found useful for treating bacterial and viral diseases including herpes, influenza, SARS, hepatitis and tuberculosis (New Scientist, 2016; Pleszczyńska et al, 2017). Polyporenic acid C is considered a “promising agent” in lung cancer therapy, because of its ability to induce cancer cell apoptosis (death) (Ling et al, 2009).

A closing mention should be given to the other polypore found on Ötzi, Fomes fomentarius aka Tinder Fungus, Horse Hoof Fungus and Tinder Conk, presumed to be his firelighter, which is now used to make a sustainable tough fabric. History also demonstrates its use as a styptic and absorbing wound bandage, while more recent research has proven its cytotoxic and anti-tumour effects too (Grienke et al, 2014).

Perhaps our primitive ancestors were not so primitive after all.


Capasso, L. (1998). 5300 years ago, the Ice Man used natural laxatives and antibiotics. The Lancet, 352(9143), 1864.

Dickson, J. H., Oeggl, K. D., Kofler, W., Hofbauer, W. K., Porley, R., Rothero, G. P., … Heiss, A. G. (2019). Seventy-five mosses and liverworts found frozen with the late Neolithic Tyrolean Iceman: Origins, taphonomy and the Iceman’s last journey. PLOS ONE, 14(10), e0223752.

Grienke, U; Zöll, M; Peintner, U & Rollinger, J, M. (2014). European medicinal polypores—A modern view on traditional uses. J Ethnopharmacol 154:564–583. doi:10.1016/j.jep.2014.04.030

Ling, H., Zhou, L., Jia, X., Gapter, L. A., Agarwal, R., & Ng, K. Y. (2009). Polyporenic acid C induces caspase-8-mediated apoptosis in human lung cancer A549 cells. Molecular Carcinogenesis, 48(6), 498–507.

Oeggl, K; Kofler, W; Schmidl, A; Dickson, J, H; Egarter-Vigl, E & Gaber, O. (2007). The reconstruction of the last itinerary of “Ötzi”, the Neolithic Iceman, by pollen analyses from sequentially sampled gut extracts. Quat Sci Rev.;26(7): 853–61.

Pleszczyńska, M., Lemieszek, M. K., Siwulski, M., Wiater, A., Rzeski, W., & Szczodrak, J. (2017). Fomitopsis betulina (formerly Piptoporus betulinus): the Iceman’s polypore fungus with modern biotechnological potential. World Journal of Microbiology and Biotechnology, 33(5).

Schiffman, R. (2016). The mushroom man who wants the world to take fungi seriously. Retrieved September 26, 2021, from New Scientist website

Always stay safe when foraging. You need to be 100% sure of your identification, 100% sure that your foraged item is edible, and 100% sure that you are not allergic to it (it is good practice to always try a small amount of any new food you are consuming). If in doubt, leave it out!