Oak Apples?

[Muddypause]

I've been growing a little oak tree from an acorn in a pot; it's two or three years old now, and stands about 6 inches high.

This year, I seem to have a nice crop of green and red, succulent-looking oak apples, presumably the work of some insect. They're about the size of a pea. Now, all the oak apples I've seen before were hard galls growing from the wood, not the leaves.

Anybody know what these might be all about? Are they likely to do any lasting harm?

Below are two clickable thumbnail images (I've been experimenting with free image hosts again - this time www.photobucket.com which seems to work)


Look closely under the leaves; you will see some strange fruit


And in closeup

[Lyds]

My book says this is the work of the gall wasp. It should turn brown in autumn when the wasp comes out. Not much of a book - does'nt say if it will harm the plant!

[Wombat]

G'day Guys,

i am pretty sure that gall wasps don't harm the plant (with the exception of the galls of course! )

Nev

[Muddypause]

Thanks, you two.

I've just been searching Google Images for 'gall wasp', and the nearest I can find is this, which is a Cherry Gall http://www.theimagefile.com/?p_scope=pu ... F;id=22198 though it doesn't look quite as translucent as the ones I have.

However, another site says this, of the Cherry Gall:

"Attractive spherical galls on the underside of oak leaves caused by larvae of gall wasp Diplolepis quercusfolii. Individual galls often grade from bright red to green. Adults emerge in winter and subsequent generation found in oak buds."

I'm not quite sure if that last sentence implies that there is lasting damage to the plant.

I've just looked at them closely tonight, and there already seem to be some exit holes in the galls, which seems very early - the leaves are only a few weeks old.

[Lyds]

Muddypause says:

I've just looked at them closely tonight, and there already seem to be some exit holes in the galls, which seems very early - the leaves are only a few weeks old.


Perhaps they know something.........

[Muddypause]

Perhaps they know something.........

"So long, and thanks for all the acorns"?

[Wombat]

Love it!

[leedarkwood]

the old galls are 50% tannin, and used once in inks, tanning and medicine.

Lee

[Wombat]

Good point Lee, I had forgotten that!

Nev