Bird Nest Scale / Beech Scale
Scientific Name: Cryptococcus fagisuga
Order & Family: Hemiptera; Eriococcidae
Size: 0.5 mm to 1.0 mm (adult females)

Natural Habitat
Found on the bark of beech trees (Fagus sylvatica and Fagus grandifolia) in forests and parks.
Diet & Feeding
Plant sap; they use piercing-sucking mouthparts to feed on the parenchyma of the host tree's bark.
Behavior Patterns
They are largely immobile as adults, living under a protective white, woolly waxy secretion. They reproduce parenthogenetically, with eggs hatching into mobile 'crawlers' that disperse by wind or animal contact.
Risks & Benefits
Risk: Feeding damage creates entry points for Nectria fungi, leading to Beech Bark Disease which can kill the host tree. Benefit: They serve as a food source for some lady beetles and other predatory insects.
Identified on: 4/16/2026