Plant Protection - Leaf Spot of Photinia
Host: Red Tip Photinia (Photinia x fraseri)
Disease common name: Leaf Spot
Disease scientific name: Entomosporium
Severity: Can be fatal if untreated; progresses slowly over several years; defoliation can be total early in season, causing serious weakening
Symptoms:
Gross:Spotted leaves with unthrifty appearance to plant; partial to total defoliation
Specific:
Leaves -
Small purple spots enlarging to brown lesions
Raised black dot in center of lesion
Defoliation if spots are numerous
Twigs and shoots -
Midsummer lesions on new current year's twigs
Purple-black areas coalesce to form a canker
Lesions on older wood may go back several years and indicate chronic infection
Contributing factors:
Presence of pathogen in twig cankers
Moist weather during red leaf expansion
Control:
Removal of twigs at least one year beyond the oldest cankers
Cleanup of debris beneath tree
Chemical protection – Funginex, Daconil 2787 or Benlate in rotation
Avoid planting near members of the Rose family, particularly Pear or Quince, which may serve as sources of infection
Resistant varieties – none known
Entomosporium or Leaf Spot Disease of Photinia is potentially a very serious disease if left uncontrolled, resulting in defoliation, stunting and death of the plant. Disease spread in the nursery is rapid, especially if overhead sprinklers are used. Cutting material should never be taken from infested or suspect plants or from plants within infective distance from diseased plants.
READ AND FOLLOW ALL LABEL DIRECTIONS AS IMPROPER USE OF PESTICIDES MAY AFFECT ANIMAL AND HUMAN HEALTH.
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