What is this?

[dking193]

This is growing on a wild muscadine at the back of the property. Can't find anything like it on the web and I don't want it to get to my good muscadine and grape vines. Any ideas

 

[dwhill40]

Look up grape leaf phylloxera on google images.

 

[dking193]

That is an awful pest. Don't want it near my grapes so, its getting gut down tomorrow. Thanks for the info!

 

[whackfol]

Is phylloxera the only possible diagnosis? Are there other causes for gall on the underside of leaves? ... Not disagreeing, just asking.

 

[GreginND]

It sure looks like phylloxera gall to me.

Here's some more information about insects that produce grape leaf galls. The only thing that looks like what you have is phylloxera.

http://www.oardc.ohio-state.edu/grapeipm/insects_attacking_grape_foliage.htm

 

[dking193]

I put the wild muscadines down this morning. Checked my grape leaves and found a few on them as well. They will get a good spaying this afternoon and I've pulled all infected leaves.