Apple tree , one half dying

Question

Two major branches on one side appear dead, with no blossoms at all. Other branches are showing lots of blossoms.

Answer 1

There are several diseases that can cause branches to die on apple trees. One of the most serious is fire blight, which you can learn about in this article:
http://ipm.ucanr.edu/PMG/PESTNOTES/pn7414.html

Black rot limb canker and collar rot are other possible causes. See the following articles for more information:
https://www.gardeningknowhow.com/edible/fruits/apples/apple-tree-diseases.htm
https://www.rhs.org.uk/advice/profile?PID=769#section-3

You may want to contact our local extension office for help figuring out what is wrong with your tree and whether it can be treated.