 Spores are produced in basidia that are arranged in a vertically arranged layer of minute tubes on the underside of the cap that create a surface of pores . This surface is whitish when young before turning dull pink or flesh @-@ colored in maturity . When bruised , the pore surface initially stains reddish and slowly turns black . The shape of the pores is angular to irregular , and they are small , with roughly two pores per millimeter . The tubes are 5 – 10 mm ( 0 @.@ 2 – 0 @.@ 4 in ) deep , and usually sunken around the area of attachment to the stem . The stem is 4 – 10 cm ( 1 @.@ 6 – 3 @.@ 9 in ) long by 2 – 4 cm ( 0 @.@ 8 – 1 @.@ 6 in ) thick , and is equal in width throughout its length , slightly thicker towards the base , or somewhat thicker in the middle . It is the same color as the cap , or paler . The surface texture of the stem is usually smooth , although some specimens may be slightly reticulated near the top . The spore print can range from pinkish to a deep flesh color . 
