Symptoms Tip blight symptoms appear about three weeks after budbreak and include tan to brown discoloration and wilting or crooking of succulent shoot tips, and a V-shaped pattern of tan discoloration at the base of leaves along the midvein. Just before or coinciding with bloom, a white spore-bearing fungal mantle appears on the crooked portions of infected shoots and flower peduncles. Tip blight occurrence is typically spotty in beds and can be overlooked as infected shoots are overgrown by healthy shoots. Infected fruit fail to ripen normally. Brown, necrotic bands appear lengthwise on the berry and spread until the entire berry is yellowish-brown.
Some infected berries turn dark brown and shriveled, and are referred to as mummies.
Ascospores are released for a period of 25-35 days, corresponding to the period between budbreak and bloom. Conidia infect open flowers, and eventually fungal mycelia fill the infected berries. Check out the cottonball disease cycle page. Control Cranberry beds should be clean picked to avoid leaving in the field mummified fruit in which the cottonball fungus overwinters. Currently, sterol demethylation inhibitor fungicides are used to control cottonball.