Letter from an expert on how not to poison yourself with mushrooms, though one of his points may be due to lack of clarity on Y's part in a previous essay in this dangerous territory. David Fuller, mycologist in the Department of Botany in University College, Dublin writes comprehensively:
"I read your piece on `Mushrooms Galore' on Thursday, October 2nd and am a bit uneasy about your advice to mushroom hunters. You wrote that if you recognise the fungus as safe you should cut it neatly at the base or otherwise remove the whole foot, which makes identification easier.
"Features of the stipe/foot can be very important in identifying mushrooms and in distinguishing edible from poisonous species. For example, in the case of Amanita species, many of which are poisonous, some fatally, the presence of a cup-like volva at the base of the stipe is a crucial distinguishing feature. Amanita phalloides, the `Death Cap Fungus', is responsible for c.85 per cent of mushroom deaths, usually as a result of it being mistaken for the edible field mushroom. In addition to a volva at the base of the stipe, Amanita spp. also have white gills and spores. "The `Parasol Fungus', Macrolepiota procera, is one of the more desirable edible wild mushrooms. Anther very similar species is the `Shaggy Parasol' Macrolepiota rhacodes, which can cause illness in some individuals. Differences in markings on the stipes of the mushrooms are used in distinguishing the two species.
"Membranous rings are found on the stipes of some mushrooms and their characteristics are also used in distinguishing species. Features of the ring are very helpful in recognising the edible `Horse Mushroom', Agaricus arvensis, which can be mistaken for the poisonous `Yellow-staining Mushroom', Agaricus xanthodermus. "I've cited just a few examples which immediately come to mind - there are others. Accordingly, I would have to disagree with your advice that removal of the foot makes identification easier. On the contrary, it may make identification more difficult and perhaps result in misidentification."
The lines on October 2nd to which he refers; "if you recognise the fungus as safe, cut it neatly at the base; otherwise remove the whole foot, which makes identification easier", was meant to convey:" Remove the foot from the ground and inspect." But thanks for the many identifications and warnings.