We have a problem!!

Our garden is surrounded by a few trees and a month ago, everything looked fine.
But ..
Something seems to attacked the leaves!
First, they changed colour and now they have fallen off!
I suspect the cause could be an infestation by burrowing insects or perhaps some nasty fungus has destroyed them!
Can anyone out there in blip land help?
Out trees will soon look like the title of this track!
We are looking after Coco for a few days and she's lovely.
P.S. After reading my title again, I can't help thinking about Houston!!