What is this from my Red Oak Tree?

[MQ32Shooter]

Every year about this time I see these things in my yard under my Red Oak. It's about the size of a quail egg. Please don't say it's an acorn cause it really don't look like any acorn I've ever seen. The tree is already full of small acorn clusters also.

[Playa]

Spore of some sort. I see them on the ground in the fall when they are dried up and have fallen.

[oktx]

An oak gall. Gall wasp.

[MQ32Shooter]

An oak gall.

What is that? Is it harmful to the tree?

[oktx]

http://old.isatexas.com/Members/Pests/Pests.htm

What is that? Is it harmful to the tree?

I don't think so. A wasp makes it.

[JMoore85]

Kinda cool looking

[MQ32Shooter]

http://old.isatexas.com/Members/Pests/Pests.htm
I don't think so. A wasp makes it.

Man, thanks for the quick, correct response. The link you provided was excellent!

[oktx]

Man, thanks for the quick, correct response. The link you provided was excellent!

You bet!