Brown spots, yellow leaves on willow
I have a recently (about 3 months ago) planted curly willow that has a handful of leaves with brown spots, which then turn yellow. The tree has grown quite a bit and has a lot of healthy growth but if this is a problem I want to tackle it sooner rather than later.
It looks like it just has some fungal leaf spots, probably caused from all of the recent rains we have had. Use a fungicide containing chlorothalonil to control it and keep it from spreading. Daconil is a common brand containing chlorothalonil.