"Mike Derby" wrote in message
...

"Malcolm H" wrote in a message:
Please see these pictures:

http://picasaweb.google.co.uk/mphear...99535032005154

We have several oak trees in our neighbourhood, where we have lived for
over 30 years, and the first time we have noticed that some ( about
5-10%)
of the fallen acorns have these growths.

Please can anybody explain what they are?
---
Good photos, they're Knopper Galls. Gall wasps are the culprits.
Google the RHS advice pages and read all about them.

MD

Thank you Gentlemen for your expert advice, I'm sure you are correct.

I have added two more pictures to the album, one showing an insect nest in a
neighbouring tree and the other showing the foliage of the tree. Please
could you identify what sort of insect nest it is (could it be a Gall Wasp
nest?) also please could you identify the tree (some kind of Cotoneasta?).

http://picasaweb.google.co.uk/mphear...y=-AN0HKOPy2k#