These two fungi are very similar morphologically and can be definitively separated only by microscopic examination of the sexual fruiting structures. These structures, called perithecia, are not frequently found. Usually, the first symptoms of infection are dead twigs and dieback. Leaves above stem infections droop and discolor through shades of green to various shades of brown, and often remain attached, sometimes through the winter. These flags are caused by stem invasions and girdling or near-girdling cankers immediately below the flag.
Cankers are dark and depressed areas of dead bark and wood on main leaders and branches.
Canker margins are sharp and distinct on the bark and discolored wood. Cankers are frequently perennial and may assume a zonate appearance. Young cankers usually exude gum at the margin and may have a sour, sap odor. The surface of the cankers may develop raised pinhead-sized pycnidia in the bark. The spore-forming structures are rarely produced on cherry stems.