Eriosoma lanuginosum

Alt Name
Egg Gall

Eriosoma lanuginosum is an aphid which causes the formation of a leaf gall on Elm which takes the form of a bladder looking like a pale green egg or pear which may be 6 or even 8 cm long and nearly as wide. The gall is more often seen than the adult aphid.


On elms, usually small leaved elms

When to see it

Look for galls in June and July although they may persist over winter in a hardened form.

Life History

Aphids feed inside the gall protected from predators.

UK Status

Uncommon in Britain.

VC55 Status

Uncommon in Leicestershire and Rutland.

Leicestershire & Rutland Map

UK Map