We moved into our new house in January and the garden has a row of what I think is ceder, very mature and well established. However at least half of it appears to be dead and the rest dying. Is there anything I can do to help bring it back or is it tree surgeon and removal time? I think it's going to cost £££ to remove and concerned it's going to damage the beds and pond around. Any advice? We're talking at least 10 trees that would need to go.