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The Oyster Mushroom (Edible) 

 Pleurotus ostrcatns Jacq. 



This plant is called the oyster mushroom because the shape of the 

 plant sometimes resembles the outline of an oyster-shell. It grows 

 from May to December on dead trunks and branches of trees, or some- 

 times from wounds of living trees, usually in crowded clusters of 

 several individuals with the caps overlapping each other. It is some- 

 times practically stemless, but other specimens may have a very defi- 

 nite stem, which, however, is always lateral, that is, at one side of 

 the cap rather than at the center. The shape of the plant depends 

 largely on its position. Plants growing from the upper side of a fallen 

 log are quite different in shape from those growing from the side of 

 the trunk or stump, since, wherever they grow, thev must bring the 

 gills into a horizontal or nearly horizontal position in order that the 

 spores may be liberated. Pleurotus ostrcatus is a very common and 

 often abundant mushroom, and one that is very easy for the beginner 

 to identify. 



The cap is 5 to 20 cm. (2 to 8 inches) broad, soft and fleshy, quite 

 thin at the margin, but thicker toward the place of attachment. It 

 may be attached directly to the wood at one side or it may be nar- 

 rowed into a short stem, and it is broadest at the outer extremity. It 

 is usually depressed on the upper side near the place of attachment, 

 and the margin is often incurved. The surface is moist or dry and 

 smooth, but sometimes more or less torn into scale-like appendages. 

 The color varies from white to gray or brown. The flesh is white. 



The gills are broad, white, not much crowded, and when a stem is 

 present they run out on it (decurrent) and narrow ( ut into vein-like 

 lines which branch and connect with each other. The spores are white 

 or pale lilac. 



The stem when present is short, firm, white, usually thickened up- 

 ward, and often hairv at the base. There is no ring and no volva. 



This mushroom is a favorite with many mushroom-eaters, but only 

 young plants should be used and they must be carefully and thoroughly 

 cooked or they will be tough. When dipped in beaten egg, then in 

 bread crumbs, and fried in verv hot fat, they are excellent. 



Collected in Champaign and Union counties. 



