Hi- I'm a new poster, but I'm about at my wit's end with the ('Radiant' and 'Thunderchild') crab apple trees I planted several years ago. Every single spring, their leaves develop spots and start curling up, until (within perhaps a month), they have lost all their leaves. I have little experience with crab trees, so I've tried to researcn the issue, but can't come up with anything that seems to parallel the issue, except rust.

I've treated for rust each year with anti-fungal sprays, but have had absolutely zero success. I do have a cedar hedge quite near the trees, and am wondering if it IS rust, and if nothing short of removing the hedge (that's not happening) will suffice to cure the trees' ills. Can anyone help?

Thanks in advance for any wisdom/ suggestions!