 Strobilurus tenacellus , commonly known as the pinecone cap , is a species of agaric fungus in the family Physalacriaceae . It is found in Asia and Europe , where it grows on the fallen cones of pine and spruce trees . The fruit bodies ( mushrooms ) are small , with convex to flat , reddish to brownish caps up to 15 mm ( 0 @.@ 6 in ) in diameter , set atop thin cylindrical stems up to 4 – 7 @.@ 5 cm ( 1 @.@ 6 – 3 @.@ 0 in ) long with a rooting base . A characteristic microscopic feature of the mushroom is the sharp , thin @-@ walled cystidia found on the stipe , gills , and cap . The mushrooms , sometimes described as edible , are too small to be of culinary interest . The fungus releases compounds called strobilurins that suppress the growth and development of other fungi . Derivatives of these compounds are used as an important class of agricultural fungicides . 
