There are many reasons to prune your trees, but the essential message is that it keeps them healthy! Removing dead, competing, decaying or diseased limbs and will greatly benefit the longevity of your tree. If these remain on the tree they can become a magnet for other diseases and insects that will establish in the dead branches and spread into the rest of the canopy. Pruning can also benefit your view, or keep branches away from your building or driveway.
View Clearance in a 100ft Ponderosa Pine
Western Gall Rust in a Ponderosa Pine
Dwarf Mistletoe in a Douglas fir
Topping trees has been a common practice since humans have been cultivating trees. However this practice has been founded as extremely detrimental to tree health and creates structural defects in the coming years. Here is a cavity that developed in a cottonwood after a large topping cut. Often, the branches that grow out of a cut like this are not well-attached and are prone to breaking off in the future.