Horse chestnut scale

Horse chestnut scale became established in London in the 1960s and has since spread throughout England and into Wales. The white egg masses are often noticed on the trunks and branches of trees and shrubs but it causes no serious damage. 

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Horse chestnut scale

Quick facts

Common name Horse chestnut scale
Latin name Pulvinaria regalis
Plants affected Horse chestnut, lime (Tilia), sycamore, maples and other Acer spp., elm, bay, magnolia, Cornus spp.
Main symptoms In early summer, white circular egg masses, partly covered by brown shells, appear on the trunks and larger branches
Caused by A sap-sucking insect
Timing May-August

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