WSU CAHNRS and WSU Extension


Search plant problems by plant name

? Help on search

A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  R  S  T  V  W  Y 

Plant NameTypeDescription 
Bacterial blightEuonymusDiseaseBacterial blight causes shoots to blacken and die back. Leaf spotting caused by the blight is infrequent on euonymus, but common on other plant species. Infection is favored by moist weather. Wounds are frequent infection sites, especially those caused by frost damage. The bacterium which causes the blight is easily spread by splashing water, wind, insects, and contaminated pruning tools. Bacterial blight is also common on lilac, maple, cherry, and many other woody plants.
Crown gallEuonymusDiseaseCrown gall is caused by a soilborne bacterium. The bacteria infect through wounds on the stems, crown, and roots. Young galls are fleshy, white to greenish, and look like cauliflower when above ground. Older galls are hardened and turn dark brown and woody or corky in appearance. The bacteria can be spread from infected to clean soil by water movement. Damage to plants varies with location and size of galls and is usually minimal, although the stem can be somewhat weakened at the gall site. The growths can be an aesthetic concern.
Powdery mildewEuonymusDiseasePowdery mildew is a fungal disease of the leaves of Euonymus japonica (evergreen euonymus). Characteristic patches of gray-white, powdery fungus are found in thick mats on the upper and lower leaf surfaces. Affected leaves may be distorted, turn yellow and drop. The disease is spread by wind-blown spores and is favored by shade and humid conditions with warm days and cool nights. The disease is inhibited by rainy weather, however. The fungus overwinters on leaf debris and on the host plant.
Euonymus scaleEuonymusInsectEuonymus scale females are dark, 1/16" long, and mussel-shaped. The males are narrow, elongate, and white. Euonymus scales are found on both leaves and stems. Infested leaves develop yellow to white spots from scale feeding. Crawlers are orange and first emerge in the spring (there are 2-3 generations/year) from beneath the shells of overwintering mature females. Euonymus scale is also reported to infest bittersweet (Celastrus spp.) and pachysandra.