Master Gardener: Apple tree likely hit by bacterial infection

Question: I have an apple tree that has developed several twigs with brown, dead-looking leaves and flowers. I don’t see any insects and the rest of the tree looks fine. Do you know what the problem might be?
Answer: I suspect that you are seeing the evidence of fireblight — a bacterial infection caused by the pathogen Erwinia amylovora.
Apple and pear trees are quite susceptible to it, as are ornamentals such as pyracantha. Bees carry the bacteria from flowers of infected twigs to o