Birch aphids

Birch aphids are common on leaves of birch. According to Aphids on World Plants, there are 72 species of aphids in 18 genera feeding on Betula species. The PNW Insect Management Handbook lists the aphid, Euceraphis betulae on birch. This species is associated with Betula pendula, European silver birch.

Young aphid nymphs hatch (eclose) from overwintering eggs in late April or May. These aphids will feed and soon reach adult stages. They can reproduce without mating so populations of aphids on the spring growth can enlarge rapidly.

Monitor for the eggs near buds and the aphids on new growth and leaf undersides.

For information on management of aphids, check the PNW Insect Management Handbook.

Web resources:

Euceraphis betulae, Silver birch aphid Natural History Museum. Great site from the United Kingdom with nice images and good detail

Birch Aphid: Insects and Diseases of Alaskan Forests. USDA-Forest Service. R10-TP-87 April 2001. Search under the Index to Insects by Host Plants on the navigation bar.

Blackman, R. and J Holopainen. A year in the life of a birch aphid.

Aphids on Worlds Plants website: Betula-A detailed key of aphids listed on birch species.

Birch aphid eggs overwintering near leaf bud

Photo: Ken Gray

Young nymphs on expanding foliage

Photo: Eric Smith

Winged adult (alate) birch aphid

Photo: Ken Gray

Page last modified 5/6/11