What is deadwood?

The answer is in question;

What is paralysis (فالج) in humans?

Or in case of diabetes patients why doctors suggest to cut the foot in certain cases???

Well…

The plants are made up of cells. The water and minerals move through roots to the end point is through the cells. One cell pass it to the other one and so the process continues. I would try to give you some insight for better understanding. Sometimes disease some disease kill the last cells of end point or edge of a branch. As the cell dies so movement chain disturbs and disease come one step forward and then next cell dies due to disease, again minerals can not reach there so another cell dies… This is a horrible process. One by one cells start dieing. This is a slow poison till some certain stage. As the disease get some good proportion of branch, it speeds up by killing all the cells of a plant… Therefore it is better, when you see any dead branch prune it immediately…

How can you judge???

Very easy… Just give your plant 30 seconds… Observe it thoroughly, you will definitely found the difference in dead wood and the living wood through its color and its physical appearance.