Fungus so humongous it's punny

For eight years, Kew Gardens has held the record of the largest (observed) fungal fruiting body in the world. In 2003 a specimen of Rigidoporus ulmarius was measured at just over 1.5 metres in diameter and 4 metres around the circumference. As the species names suggests, it grows normally grows on elms but I wouldn't be surprised if 'the big one' grew on a Horse Chestnut here in Kew Gardens (just a hunch and really I should check!).

According to today's Observer ("When you can't see the wood for the fungus, you'd have to call it humungous" - yes seriously - and as reported on various media pages on the web, such as BBC online, over the last week), that record has been broken. Not by the Natural History Museum - it would be too much to bear if a mushroom sprouting from the Cocoon was bigger and better than one at Kew (not that there is any competition between the two august organisations) - but by a discovery in the Hainan Province of  China by Professor Yu-Cheng Dai from the Chinese Academy of Sciences in Shenyang.

This fantastic fungus (alliteration, rhyming and punning are rife in any report of a fun-guy fact) is "10 metres long, 80 cm wide and weighs half a tonne", according to today's Observer. I like the quote they include form Professor Dai that "a small piece of the fruiting body is almost like my size".

The name of the phenomenal fungus is Fomitiporia ellipsoidea, again a kind of bracket fungus, and thought to be about 20 years old. I gather it's a newly described species, first discovered in Fujian Province in 2008, and published in Fungal Biology. The particularly tremendous 'toadstool' was discovered last year on an oak tree.

As you know, these kinds of records are never particularly secure. I found one report, and I'm sure there are others, of a counter record for the largest fungal fruiting body even before this China find. From Oregon, USA, we have a specimen of Bridgeoporus nobilissimus, boasting to be not only the biggest in the world but a mycological mystery.

While these are massive 'mushrooms', the first forest fungi may all have been around six feet tall, as I reported some time ago. As I reported then, somewhat inaccurately, today's fungi aren't (generally, as it turns out) so big above the ground.

Remember that these mycological media-stars, the two bracket fungi, are just the tip of an mycelial iceberg. The toadstool or mushroom you see in your garden or forest may belong to a single organism up to 30 metres across. In one documented example, an armillaria fungus spread through 15 hectares of soil and weighed in total 10 tonnes.

Just for the record, fungi (underground and above) are probably the biggest organisms on earth. That's a fungal fact worth telling your friends while mangiare mycopasta.

Image: This picture of the Chinese fungus and its discoverer is pasted all over the net so I'm assuming it's OK to reproduce here...