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Plant NameTypeDescription 
Leaf spot (Diplocarpon)PhotiniaDiseaseFungal leaf spot of photinia is characterized by the presence of red to purple spots on the leaves. The spots are small at first, but soon enlarge and develop brown to grayish necrotic centers. Small dark fruiting bodies of the fungus can sometimes be seen in the center of the spots. Severely infected leaves may drop, sometimes resulting in considerable defoliation. The disease can be spread by splashing water and overwinters on diseased plant tissues. New growth is particularly susceptible. In western Washington, photinia may develop a physiological leaf spot that resembles fungal leaf spot.
Physiological leaf spotPhotiniaDiseasePhysiological leaf spot occurs on Photinia in western Washington. The symptoms resemble those of early fungal leaf spot infections. Small red to purple spots appear on the leaves, but do not develop the dark centers characteristic of fungal leaf spot infections. This problem is more common than fungal leaf spot. It causes little damage to plants, although some leaf drop may occur. While the cause of this problem is unknown, leaf spotting appears to be more severe on plants in low-lying or shady areas. Cold temperatures appear to be involved.
Powdery mildewPhotiniaDiseasePowdery mildew is a fungal disease found on leaves and shoots of photinia. Characteristic patches of gray-white, powdery fungus are found in thick mats on the upper and lower leaf surfaces. The infected areas may develop fungal fruiting bodies which appear as small black specks on the white mats. Affected leaves may be distorted, turn yellow and drop. The disease is spread by wind-blown spores and is favored by shade, humid conditions, and warm days and cool nights. The fungus overwinters on buds of the host plant and in leaf debris.
AphidsPhotiniaInsectAphids on photinia are variously colored, from yellowish or greenish to black. They are soft-bodied insects less than 1/8" long. Aphids often feed in large groups and typically are found on new growth, including both leaves and shoots. Heavy infestations can cause yellowing or wilting of foliage. New growth may be stunted. Aphids often produce honeydew, a sweet, sticky material that may attract ants or become covered with a growth of dark sooty mold.
Root weevilsPhotiniaInsectRoot weevil larvae feed on the roots and bark of plants. Feeding typically occurs near the crown region. The white grubs are found in the soil around the roots. Heavy feeding by root weevil larvae can cause girdling of roots or crown, resulting in decline or death of the plant. Adults may feed on leaves, causing minor to severe notching of leaf margins. Adult root weevils range in size from 1/4" to 1/2" long. They are brownish to black, flightless beetles which climb into the foliage to feed at night.