Oak tree - acorns attacked

 Our 30 year old oak tree has virtually every acorn attacked by
something...
http://www.telmek.net/pics/acorn.jpg
Is this some kind of bug we can/should do anything about?
The tree itself looks fine apart from this.
thanks

 On Sun, 07 Aug 2011 15:08:27 +0100, dave wrote:


Looks like  Andricus quercuscalicis, the knopper gall.  A tiny wasp takes
over the developing acorn.

I think they are fascinating.  Doesn't harm the tree, after all an oak
can live for 800 years, and only needs one or two of its millions of
acorns to germinate in that time.  It can impact on spercies that depend
on acorns for food, and commercial growers

I have two oaks in my garden, and for 20 years one was heavily infested -
around 80% of the acorns affected.  Then one year it stopped happening &
I havn't seen it since.

Said to have appeared from Germany in the 1960s, I reckon it had a free
run until its own parasites caught up with it, either naturally or by the
artificial  introduction of biological controls





--
Bob Harvey