tree deaths

I bought a place two years ago with many trees. I've noticed some of the trees seemed to be partially dead but "healthy" parts almost appear to be doing just fine (Picture 1 of the tree, Picture 2 on the leaves). Throughout the summers, I also noticed some smaller trees just appear to die almost...

As arborist we hope to lessen tree hazards to persons by inspecting and controlling urban tree risks.. But each year the numbers tend to say 80 - 100 of us die doing our job. While each year about 100 public persons are killed by falling trees. So my hypothetical is,, what if we stopped...