are they scales?

Asked April 24, 2019, 10:52 PM EDT

found them at one of my customer. looks like scales to me, their body are soft. or maybe i'm wrong. the tree is newly planted ( 6 months). found the bug on 2 other trees.

District of Columbia County District of Columbia insect issues scale insects insect or spider id calico scale black and white bumps on tree

1 Response

This is calico scale. Big, isn't it?

This scale is usually controlled by beneficial insects. Unless honeydew and sooty mold are a problem, no action is needed in light infestations, which seems to be the case here. You can manually scrape these few off the tree now, to ensure they don't spread.

In heavy infestation, you'll have to spray an horticultural oil with a systemic insecticide in April or early May.
Refer to "Managing Insects and Mites on Wood Plants: an IPM Approach" for further details.