Train Wrecker in pious pine

What do you do when you find this ginormous fungus in one of the trees at Kew Gardens? Each fruiting body is about a foot across and the cluster is situated four or more metres above the ground.

Well you ask the experts of course, and many of them are sitting close by, next to the largest collection of preserved fungi in the world.

Martyn Ainsworth, our Senior Researcher in Fungal Conservation, was right on to it. During his lunch break this week he trekked down to the Bishop Pine (Pinus muricata), near the lilac collection, and saw the great big fruiting bodies in my picture above.

He asked one of the 'arb team' who just happened to be nearby chopping down trees, or tree limbs, to sample a little of the fungal cluster. They obliged and he took the sample to his laboratory to check out its microscopic structure - that's the way to identify things like fungi (and algae).

The verdict? Neolentinus lepideus. It used to just plain old Lentinus lepideus but Martyn's mycological colleagues have been hard at work revising the classification and making sure it all makes sense.

In North America, its homeland, this fungus carries the evocative and rather threatening common name of Train Wrecker. According to Martyn it will rot utility poles and rail sleepers. Not something you want hanging around railway yards.

It also causes what is called a brown rot in dead conifer wood, clearly something that exists a few metres up in our Bishop Pine. But perhaps it's not a big concern for the future of our tree. Martyn found records of the fungus in our Kew Fungarium (that big collection of preserved fungi) and it turns out it has been fruiting on and off in Kew Gardens since at least 1997, and probably in the same tree.

Now just in case you are crafting away in your workshop on a piece of Bishop Pine, or another conifer, and it sprouts giant fruiting bodies like this, it's a tough old fungus and resistant even to creosote. So just put down your tools, sit back, and enjoy.

(It's host, Pinus muricata is a coastal species in California and nearby parts of North America. It was discovered in 1835 near Mission San Luis Obispo, and thus christened the 'Bishop' pine.)

As a good citizen scientist/naturalist, I've recorded this sighting on iNaturalist.