Practically everybody must have come across these weird blackish blobs sitting on dead logs or standing trunks at some time; some people may even be surprised at their charcoal-like consistency, and thanks to Ray Mears, we can all have lots of fun with them.

In Britain, these are usually found on Fraxinus and the scientific name is Daldinia concentrica, but occasionally these are also found on other trees and especially burnt gorse. In fact the species on gorse is so different in having a barely visible stalk that it has long been called D. vernicosa, although this name has recently been changed to D. fissa.

Over the years this genus, like so many others, has come under close scrutiny, and in Britain it is now recognised we have 7 different species. To try to keep things simple, those found on Fraxinus, Fagus and Sorbus will usually be D. concentrica, on Betula, D. loculata, and Ulmus, D. grandis. Daldinia decipiens can also occur on Betula, but this is very rare in Britain; and also Daldinia caldariorum can be found on burnt gorse, this too appears to be rare.

Superficially, they all look very similar, the main difference being in the spore measurements, which are not readily available to the amateur mycologist such as me. To confuse things even more, recently I was contacted by an SNS member in Stonham Aspal who told me he had a Cramp Ball growing on a dead Betula in his garden.

Knowing we have no records of D. loculata from Suffolk, I immediately went out to obtain a sample to send off to Kew hoping for confirmation.

I sent this off together with another Cramp Ball I found growing on Aesculus at Thornham Walks, but I was to be disappointed and even more confused for Kew told me the one on Aesculus was D. concentrica and the section I sent of the one on Betula was almost certainly the same, but he needed the entire specimen to be certain. So back I go to Stonham to pass on the disappointing news, but was able to come back with the whole specimen, with some bark still attached, to be passed on to Kew. Before doing so I was able to measure some spores myself and they were well within the range of ordinary D. concentrica, but at least this is the first known record of D. concentrica on Betula from Suffolk.

It would appear that D. loculata only occurs on burnt or scorched Betula, so if you come across such a specimen or indeed any Cramp ball growing on any species other than Fraxinus or burnt gorse, then please do contact me at .