white fuzzy spheres - Ask Extension
One of my bushes has numerous white fuzzy spheres growing at the leaf and branch nodes. Can you please tell me what they are, if they are damaging a...
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white fuzzy spheres #875240
Asked June 29, 2024, 1:37 PM EDT
One of my bushes has numerous white fuzzy spheres growing at the leaf and branch nodes. Can you please tell me what they are, if they are damaging and how to control them?
Larimer County Colorado
Expert Response
Hi Ken,
This is hawthorn mealybug and is a common pest on hawthorn trees. They are challenging to control because their bodies are so waxy. But the best management is done in late summer or fall as the nymphs move from branches to the trunks of the tree - and you can use horticultural oils. You can do a second application in the spring as the nymphs move to the branches for summer.
While you can use systemic insecticides, you wouldn't want to do this when the tree is in or near flower - as those insecticides can harm pollinators.
Here's more information: https://webdoc.agsci.colostate.edu/bspm/Hexapoda%20(Insects)/Hawthorn%20Mealybug%20December%202014%20Revision.pdf
This is hawthorn mealybug and is a common pest on hawthorn trees. They are challenging to control because their bodies are so waxy. But the best management is done in late summer or fall as the nymphs move from branches to the trunks of the tree - and you can use horticultural oils. You can do a second application in the spring as the nymphs move to the branches for summer.
While you can use systemic insecticides, you wouldn't want to do this when the tree is in or near flower - as those insecticides can harm pollinators.
Here's more information: https://webdoc.agsci.colostate.edu/bspm/Hexapoda%20(Insects)/Hawthorn%20Mealybug%20December%202014%20Revision.pdf
