Dasineura plicatrix Gall
The gall wasp Andricus lignicola lays eggs into the leaf axil buds and terminal buds of English Oak and Sessile Oak causing scaly, marble like galls to form. These are often referred to as Cola-nut Galls. The galls are seen more often than the adult wasps. The galls are found in small groups, which however do not coalesce, helping to prevent misidentification with the Oak Marble Gall (Andricus kollari), in addition the shape is ovoid rather than spherical. Scaly, grey at first, later brown; very hard; old galls persist for years; often in clusters of two to five; single chamber off-centre; exit hole always close to point of attachment.d it is scaly rather than smooth.
Wherever the host species occur.
When to see it
Galls are most likely to be found in early autumn, but may persist for years… Naturespot
The cynipid wasp Neuroterus quercusbaccarum has both agamic and bisexual generations which cause different galls to occur on Oak. The gall is more likely to be seen than the adult wasp.
Photo ID? Easily identified from a photo
Anywhere that Oak is present.
When to see it
As described below.
The male and female of the bisexual generation emerge in June from Currant Galls which are spherical, smooth, succulent, berry-like galls up to 7 mm in diameter which vary in colour from pale yellow through green to red or purple. These galls may occur on Oak leaves or catkins. After mating the fertilised eggs are laid by the sexual generation in the lower epidermis of the Oak leaves. The Spangle Galls develop over the winter and the insects emerge in April, laying their eggs in the catkins or lower epidermis of leaves. The cycle, an alternation of generation, then begins again… Naturespot
The Cherry Gall is caused by a tiny gall wasp, Cynips quercusfolii. It can be found on the underside of oak leaves, normally as a single gall. The grub remains in the gall after leaf-fall, emerging as an adult wasp in winter. This asexual generation will lay its eggs on the oak tree trunk which eventually mature to the sexual generation that mate and produce the more obvious galls.
The Gall is Caused by the Thistle Gall Fly – Urophora cardui which
lays its eggs on Creeping Thistle (Cirsium arvense). After hatching, the larvae burrow into the stem of the plant and form a gall (or swelling).