Apple tree disease/parasite
I have a semi-dwarf Gravenstein apple tree that was healthy last year but the ends of the limbs are dying off this year. The fruit is also buggy. The leaves are all dying on the ends. I will attach pictures. Do you know what's wrong with it and what I should do? I also have a dwarf pear tree with similar symptoms, just not as bad. Thank you!
Umatilla County Oregon
Unfortunately, it appears that you have fireblight. This is a bacterial infection that is inside the heartwood of the tree and cannot be treated for. The only solution is to prune the branches off but you will need to prune 2 feet behind the dead wood to try and eliminate the innoculum inside the tree. The bacterium, Erwinia amylovora is carried by bees during pollination so the only option is to spray an antibiotic during flowering to prevent further spread. There are commercial products available it you will need a pesticide license consultant to apply them.