Blotching on Liquid Amber trees
What a shame that you have this problem with your Liquid Amber trees and that you have lost two trees already.
Unfortunately neither myself or my colleagues are experts on trees but I do know that Liquid Amber trees are particularly susceptible to leaf scorch and canker disease but from your photograph this doesn’t seem to be the problem you have. I thought it was rust at first but that does not usually kill trees so I can only think it is some kind of fungal disease.
Can I suggest that you speak to the nursery you bought them from as they may be more knowledgeable on the trees they sell, failing that you could contact an online Tree Expert company and use the Ask the Expert facility where you can ask tree experts about your problem or if they can’t help maybe contact a local Arborist for some expert diagnosis.
Sorry I couldn’t be of more help and I hope that something can be done to save your remaining tree.
Lynn Burton - Horticultural Adviser