this is my contribution to #FungiFriday by@ewkaw
as i was out walking in the park i came to a section of the lawn that was marked off by some old wood sleepers that had been treated with creosote to keep them from rotting. it's a place i have been to many times but this time to my surprise i found a fungus that i had never seen before. it was quite peculiar looking, scaly with a large crack down the middle that exposed the pale flesh. at first it was difficult to tell whether it was growing out of the wood or the ground. i reasoned it must have been from the ground because the wood had been treated to prevent it from rotting. but the wood had been lying on the ground for decades so it had cracked and in some places grass was growing out of the top.
though the fungus was obviously old it was still firm, tough and somewhat woody. i managed to make enough space between the cap and the wood that i could determine that it was definitely growing on the wood and not in the ground. it's been an unusually warm and dry august with almost no fungi to be found other than polypores growing on trees, so i was very happy to find such an unusual specimen.
so while soft young fungi growing in the wild may be edible, eating one grown on treated wood entails ingesting creosote. as the name implies, rotten railroad ties can cause train wrecks and indeed they did. mile after mile of the treated wood ties provided ideal growing conditions for this incredibly adapted fungus so it spread across the continents of both Europe and North America causing the steel rails to shift thereby derailing many trains. the railway companies eventually found ways of preventing this but the name train wrecker stuck.
back home, my identification app instantly recognized this to be a train wrecker Neolentinus lepideus. i quickly understood that this was a unique fungus with the amazing ability to digest creosote. that is special because wooden railway ties were specially treated specifically to prevent rotting caused by fungi. but train wrecker have extraordinary adaptations that prevent it from being poisoned while digesting the creosote. it must be mentioned that in general fungi digest their food externally by excreting enzymes to chemically break it down before attempting to absorb it. but even if the train wrecker doesn't completely break down the creosote it is still able to absorb it without being poisoned.
there is an alternative common name, scaly sawgill used often for the fungus occurring on natural untreated wood in the forest. they are certainly scaly and the gills have sawtooth like edges
now that the fungus is no longer causing train wrecks it has come into favor as a natural environmental clean up tool. in contaminated land such as some industrial waste sites it is introduced directly into the soil and breaks down the toxic waste. they like many other fungi also absorb and accumulate heavy metals. by collecting the fruiting bodies the metals can be removed from the soil. this should serves as a warning to foragers to collect fungi only in areas they know are not contaminated.
i have taken all these photos with my phone camera. do not publish them without my permission. i used AI as a reference source but all the text is my own writing. my identification app is Artsorakel