Goat Willow yellow fungus?

in Plants
Two Goat Willow trees (Salix Caprea) in our garden have acquired a yellowness on parts of their leaves during the past seven days. Other plants and trees immediately adjacent are completely unaffected. So what is this yellow blight, please? One of two trees is enormous so there's no way we could spray it.


0
Posts
https://www.rhs.org.uk/disease/tree-rusts
Billericay - Essex
Knowledge is knowing that a tomato is a fruit.
Wisdom is not putting it in a fruit salad.