[Womble]

We have four established apple trees here that suffer terribly from canker. As a result, they are a really poor shape. They also don't produce much, since once I prune off the diseased branches every year, there's not much of last year's growth left to produce fruit in the coming year!

However,  before I cut them down and plant new trees, I want to find out if I could cut off the old tree and graft a new, more canker resistant variety onto the existing root?

Any thoughts as to whether this is worth doing, and if so, how and when to go about it? 

[clydesdaleclopper]

Certainly possible and now is the time of year to do it. One thing to check though is if the rootstock is one that is canker prone.