Euceraphis betulae

Silver birch aphid

Description

Silver birch aphid Euceraphis betulae is an aphid species that feeds on the silver birch (Betula pendula), where it sucks sap from buds and leaves. It has a light green body with a bluish tinge, covered in fine wax particles, giving it a characteristic dusty appearance. The species overwinters as eggs on birch twigs, which hatch in spring. The first generation consists of winged females that reproduce parthenogenetically, leading to a rapid population increase. By mid-summer, reproduction ceases, and aphid numbers decline. In autumn, a new reproductive phase occurs, leading to the emergence of winged males and egg-laying females, which lay eggs that overwinter.

This species is widespread across Europe, occurring wherever its host tree, the silver birch, is present. It has also been introduced to North America and Australia. High population densities can lead to yellowing of leaves and the production of large amounts of honeydew, which may promote the growth of sooty mold, reducing the ornamental value of trees.

Symptom

On affected birch leaves, aphids are found on the underside, often in large groups. Their feeding causes leaf yellowing, and an abundant honeydew coating leads to the development of black sooty mold on leaves and branches.

Tree Species: Birch

Part of a plant- attacked: Leaf / Needle

Pest significance: Less harmful

Pest Category: Insects

Invasive Species: No

Present in EU: Yes