white growth on top branches of Thornless Hawthorn
We have a young tree that is recently showing a whiteish clump of growth on the top branches. I don't see this under Hawthorn diseases so am wondering what it is and what to do about it.
Jefferson County Colorado trees and shrubs
Based on your photo, this could be the Hawthorn mealy bug, a sap-sucking insect. To confirm you may bring a sample in to the Jeffco Plant Diagnostic clinic located at the Jeffco Fairgrounds ($7 fee for Jeffco residents). Here are two references to give you some guidance on evaluating the insects yourself: