What's attacking my viburnum? - Ask Extension
Many of the branches have little white globs, generally on their lower sides. Many leaves have red, orange, and black spots, often in the tissue rough...
Knowledgebase
What's attacking my viburnum? #920599
Asked October 25, 2025, 1:12 PM EDT
Many of the branches have little white globs, generally on their lower sides. Many leaves have red, orange, and black spots, often in the tissue roughly bounded by the vasculature; some are also curling.
Harford County Maryland
Expert Response
The leaf spotting looks like typical end-of-season dieback, and as this appears to be a deciduous type of Viburnum (though even the evergreen types may shed some leaves this time of year), it's not concerning. Some minor amounts of leaf spot infection may also be overlapping but is also not a threat to long-term plant health and doesn't require intervention. (A fungicide would not provide any benefit at this point anyway.)
The white material looks like the egg-laying sites of an native insect called the Two-marked Treehopper. The white waxy covering that is so prominent looks like scale insects, but in this case the shape isn't right for scale. You can learn more about this insect on the linked page. No management is needed because the egg-laying doesn't cause serious damage (or any detectable damage) to the plant. You can wipe off the residue if it's bothersome.
The drought conditions of the past couple months or so have stressed a number of trees and shrubs, and Viburnums as a group are generally not very drought-tolerant. You can monitor the shrub for watering needs to alleviate any current drought stress, which is especially important to make the plant less vulnerable to winter damage and secondary infections that can cause branch dieback (such as untreatable fungal cankers). Overall, the plant pictured appears to be in good condition, but drought stress might be a contributing factor in any leaf curling or earlier-than-average fall coloration and shedding.
Miri
The white material looks like the egg-laying sites of an native insect called the Two-marked Treehopper. The white waxy covering that is so prominent looks like scale insects, but in this case the shape isn't right for scale. You can learn more about this insect on the linked page. No management is needed because the egg-laying doesn't cause serious damage (or any detectable damage) to the plant. You can wipe off the residue if it's bothersome.
The drought conditions of the past couple months or so have stressed a number of trees and shrubs, and Viburnums as a group are generally not very drought-tolerant. You can monitor the shrub for watering needs to alleviate any current drought stress, which is especially important to make the plant less vulnerable to winter damage and secondary infections that can cause branch dieback (such as untreatable fungal cankers). Overall, the plant pictured appears to be in good condition, but drought stress might be a contributing factor in any leaf curling or earlier-than-average fall coloration and shedding.
Miri
