I have 3 apple trees grown as cordons. They were mature trees when we
moved in 10 years ago. We also have a pear tree grown in close proximity.

I noticed to my horror yesterday that one of the apple trees appears to
be almost dead. Whole branches are shrivelled with the bark peeling off
them. Under some peeling areas near the root stock it is blackened. On
branches that are showing some life the leaves and blossom are withered
and sparse.

Does this sound like fire blight? If it is I take it I need to remove
the entire tree? The two other trees in the cordon appear healthy but
I've been getting fewer apples each year and and they have had attacks
of woolly aphids.

If I replace one or all of the apple trees with new apple trees and this
is fire blight am I asking for trouble?

Many thanks in advance.
Sarah