Agaricus urinascens var. urinascens
Cap: 6-28cm across Stem: 4-12cm in length, 2-4cm diameter
from the Greek meaning 'mushroom'
begins to smell like urine
Overall: a typical Agaricus mushroom, which grows in the same habitat as Field Mushroom (Agaricus campestris), to which it is often confused for.
Stem: similar colour to the cap, the bottom half of the stem underneath the ting is scaly, whilst above the ring it is smooth. The ring is large and thick.
Flesh: white, discolouring slightly brown or reddish but not too noticeable and more often towards the stem base. Quite firm, but often well nibbled inside.
Gills: free, begin pale, greyish, then become darker with age. The very edge of the gills is usually a lighter colour to the rest of the gill.
Cap: Cream, becoming slightly brown with age. Scaly, especially in older specimens. Cap always seems to be slightly in-rolled at all stages. Sometimes discolours yellowish when damaged, especially at the cap edges.
OVERALL: a distinctive mushroom that whilst on face value looks similar to other larger Agaricus has subtle differences. The stem is 'rough' below the ring and smooth above it. The smell of this species, especially when mature, is more like ammonia or even urine (hence the scientific name). Probably under-recorded or mis-identified for other Agaricus.
HABITAT: Upland grassland, moorland edges, pasture, woodland clearings and woodland edges are all places we have encountered this species.
DISTRIBUTION: Widespread over much of the UK.
SEASON: Summer to Autumn.
EDIBILITY: Edible. Whilst younger specimens are delicious, we find the more mature specimens have a smell with them which we don't like to eat.
SMELL: with small specimens it is not really noticeable, some smell slightly almondy. More mature specimens begin to smell of ammonia or even urine.
SPORE PRINT: brown.
SIMILAR SPECIES: Horse Mushroom (Agaricus arvensis) is similar but the stem has the same texture above and below the ring and has an aniseed smell.