Galls on Holm Oak, Quercus ilex

[pleb]

Hello everyone,

These galls on Holm Oak, Quercus ilex, were found a few days ago in Cremyll and Mount Edgcume Country Park in south east Cornwall near Plymouth. Holm oak is common in the area, which is very sheltered, and the galls were also very common. In fact they were on nearly all the mature trees, saplings and even hedges that I looked at.

Dr Graham Stone from Edinburgh, who is an expert on galls, thinks that the gall causer is probably a species of the gall wasp Plagiotrochus. I have sent him some galls and he is going to try and identify the causer by rearing them to adulthood. He says:

'Three Plagiotrochus species have very recently been recorded in the UK. As a genus, Plagiotrochus tends to go for Q ilex and Q suber, and is best represented in Spain, Portugal and NW Africa, but generally also around the mediterranean rim. Of course, it might not be a Plagiotrochus! - we'll have a look see.'

Regards,

Phil Pullen