WSU Extension

Hortsense

Dogwood : Anthracnose
(revision date: 4/11/2018)


Use Integrated Pest Management (IPM) for successful plant problem management.

Biology
Dogwood anthracnose is a fungal disease of leaves and twigs. It is found mainly on the native dogwoods, especially Pacific dogwood, but can also infect some ornamental dogwoods. The leaves display small to large irregular brown blotches or occasionally purple-edged spots. The blotches are often at the tip of the leaf, triangular, and centered on the main vein. Infected leaves may drop before normal leaf fall. Twigs have sunken spots which are brown with purple edges. Dieback of infected twigs is common, with dead leaves remaining on the twig. Vigorous plants can tolerate some damage from this disease.
Management Options

Non-Chemical Management
  • Plant species which are anthracnose-resistant. Dogwoods showing very good resistance include: C. kousa 'Beni Fuji', C. kousa 'China Girl', C. kousa 'Lance Leaf', C. kousa 'Milky Way', C. kousa 'Porlock', C. kousa 'Silver Cup', C. kousa 'Snow Bird', C. kousa 'Speciosa', C. kousa 'Summer Majesty', C. kousa 'Tsukabo-no-nine', C. kousa 'Wilton', C. kousa 'Dwarf Pink', C. kousa 'Ed Mezett', C. kousa 'Satomi', C. florida hybrids, C. florida 'Spring Grove', C. florida 'Sunset', C. racemosa, C. canadensis, C. mas, C. alba, C. alternifola, C. sericea, and C. sericea 'Flaviramea'.
  • Where practical, prune and destroy infected twigs to prevent overwintering of the disease.
  • Rake and destroy all fallen leaves, both during the summer and in the fall.
  • Do not compost diseased materials.
Select non-chemical management options as your first choice!

Chemical Management
IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides

Apply at bud break and continue at 10- to 14-day intervals until dry weather. Lilly Miller Microcop Fungicide can only be applied 2 to 3 times in a season. Spectracide IMMUNOX should not be applied more frequently than every 14 days. Homeowners should not make foliar applications to trees over 10 ft tall. Consult a commercial pesticide applicator for treatment of trees and shrubs over 10 ft. tall.

Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.
  • Bonide Fung-onil Multi-Purpose Fungicide Conc
    Active ingredient: chlorothalonil  |  EPA reg no: 60063-9-4
  • GardenTech Daconil Fungicide Conc
    Active ingredient: chlorothalonil  |  EPA reg no: 67572-82-71004
  • Monterey Liqui-Cop Copper Fungicidal Garden Spray
    Active ingredient: copper-ammonia complex  |  EPA reg no: 54705-7
  • Ortho Max Garden Disease Control Conc
    Active ingredient: chlorothalonil  |  EPA reg no: 239-2522
  • Spectracide IMMUNOX Multi-Purpose Fungicide Spray Conc
    Active ingredient: myclobutanil  |  EPA reg no: 9688-123-8845
  • This list may not include all products registered for this use.
Images
    - hide images

+ Show larger images

 
Caption: Dogwood anthracnose on leaves
Photo by: R.S. Byther
Caption: Dogwood anthracnose: leaves and twigs
Photo by: R.S. Byther
Caption: Dogwood anthracnose fruiting bodies
Photo by: C.R. Foss
Caption: Dogwood anthracnose on flowers
Photo by: R.S. Byther
Caption: Dogwood anthracnose
Photo by: R.S. Byther