Q.Birch tree dieing back
My Birch trees are dieing back from the top To the bottom. Thé leafs start To Brown and slowly die. Why and can I prevent more loss?

Certified GKH Gardening Expert
It is likely a fungal infection. There are a few things that you can do, but some infections are not treatable.
You can try dolomitic lime and wettable sulfur in the soil. This is a good broad spectrum fungicide, but if that doesn't work then copper based fungicides can help as well.
The old growth will not return to health, but when the treatment starts to work there will be new growth that should be unaffected.