Blue Spot Knight

Tricholoma columbetta

from the Greek meaning 'hairy fringe' - no idea why

like a dove (white dove)

Stem: 3-9cm in length, 1-2cm diameter. The stem often goes a few cm in to the soil, white but in more mature specimens with a green, blue or violet tinge to the base.

Overall: this species is quite an obvious one from a distance, usually found in small groups. Younger specimens are white all over and more mature specimens begin to get a green, violet or blue tinge in the cap and stem base, no present in younger ones.

OVERALL: in the autumn one could easily confuse this species for being a very late St George's Mushroom (Calocybe gambosa) as it is roughly the same size, shape and colour, although if anything the Blue Spot Knight is more white. Don't let the name fool you, the 'blue spots' can be difficult to see and usually are only present in very mature specimens, younger fresh ones do not seem to have this. 


HABITAT: with both decidious and coniferous tress but more frequently found with Oak (Quercus) and Beech (Fagus).


DISTRIBUTION: mainly found in southern Wales, the south and south-east England and northern Scotland where it is Occasional, scattered records elsewhere where it is probably Uncommon.


SEASON: late summer to autumn.




EDIBILITY: 2/5, whilst it is Edible and good, it is a bit tough and people new to the world of picking wild mushrooms to eat should steer clear of white gilled mushrooms as there are some seriously poisonous species with white gills. 


EASE OF IDENTIFICATION: there are a number of medium sized white mushrooms which have white gills, this species, however, is very white rather than a cream or off white. The mushroom has no distinctive smell and its key feature is the fact it can have blue, pruple or green spots on the cap or the base of the stem as it matures. These spots and marks can be absent in younger specimens so if you are planning on eating this species ensure it has ALL the correct features.


SMELL: Not distinctive.


SIMILAR SPECIES: St George's Mushroom (Calocybe gambosa) looks very similar in size and shape but the Blue Spot Knight does not have a mealy smell and it more a white colour than cream. The Giant Funnel (Leucopaxillus giganteus) is much larger, small specimens have decurrent gills which the Blue Spot Knight does not. A few of the white milkcaps (Lactarius) are a similar size and shape but obviously the Blue Spot Knight does not produce any 'milk' when damaged. If you are planning on eating this species then be aware of all the small white Clitocybes which some, including the Fools Funnel (Clitocybe dealbeta) are deadly poisonous, the Amanita family, which shares the same coloured gills also include some seriously poisonous species.


SYNOYNMS: Agaricus columbetta Fr.

Gills: numerous for the size of the mushroom, white becoming slightly more off white as it matures.

Flesh: white with no real colour change, smell or taste. Quite tough and fibrous.

Cap: 4-11cm across. White, starts off rounded and becomes flatter as it matures, begins quite silky. Older specimens may have colours around the cap, small marks of either blue, purple or green which at first glance may not be very distinctive. Younger specimens tend not to have this. If in doubt leave it for a few days and come back and see if any colouration has developed.

Note: green/blue colouration in the base of the stem on more mature specimens.

Tel. 07533 132 129 


Manchester, Cheshire, Deeside & North Wales

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