It looks like it got hit by weed killer.

what is the hole in the fence.. why is it there.. is it new.. and what is on the other side ... a BarB??? .. a raccoon???

or did the neighbor dump something on the other side??

ken

Am I seeing webbing in your photos? (webbing, like in spider). And what do the backs of the remaining leaves look like, is there any evidence of insect or mite on close inspection of the leaf undersides?

Outside of the lattice work on the top of the fence, the fence is solid. The bottom of the fence does not go all the way to the ground, however. The neighbor has been gone for some time and the area behind the fence is not use for any recreational activity. The neighbor used to have a business supplying organic materials to the local orchards and does not use chemicals on his property. There are no plants or landscaping on the other side of the fence.

When the climbing hydrangea was smaller, we put bird netting behind it, stapled to the fence, to allow it to climb up the solid slats into the lattice work above. It has never been a source of problems in the past and is not a source of problems for the other hydrangea.

The leaves are so devastated that most of the leaves are just withered. There is some indication of insect feeding on the leaves, but this problem is something new. My initial impression is that someone hit it with a blow torch. I have looked to see if there was a fungus or other disease that would cause this, but I could find nothing substantial. We love this plant and it is so sad to see it like this.

I still don't know what the problem is, maybe someone else has clues...

But climbing hydrangea doesn't need something like bird netting to elevate itself, it doesn't twine (like clematis) but attaches itself by means adhesive aerial roots to a solid surface like fence or wall. You should have more trouble getting it to wind through the top lattice than adhering to the fence.

Here is a link that might be useful: {{gwi:273022}}