Prune only under dry conditions and sterilize pruners with alcohol between pruning cuts. Avoid planting monocultures of flowering dogwood, Cornus florida . There are no flowering dogwood cultivars known to be resistant to dogwood anthracnose. Kousa dogwood should be substituted for flowering dogwood. Infected twigs are gray or tan and may show spore producing structures, called conidiomata, which appear as raised, reddish-brown spots.
Enlargement shows magnified view of conidiomata.
Fungicide sprays are recommended only if you live in a high risk area for anthracnose or if your tree has been confined as being infected with anthracnose. Start sprays at bud break and continue spraying according to label directions. The recommended interval between sprays will vary depending on the fungicide and the rate of application. Make sure the fungicide you use has dogwood listed on the label. Follow all label instructions regarding amounts of pesticide to use, method of application and safety warnings.