The message
from Kay Easton contains these words:

Still, let's try another way .. apart from the fairy ring champignon and
C rivulosa, what else makes fairy rings?

Hundreds and hundreds and hundreds offem I'd guess. Most, if not all
Agaricus. Most, if not all Tricholoma (Lepista), most (ditto) puffballs,
Lactarius, Clitocybe, Inocybe, Lepiota - oh, and loads more.

--
Rusty Hinge
horrid·squeak&zetnet·co·uk
http://www.users.zetnet.co.uk/hi-fi/tqt.htm