Abiotic Tree Injury
As common as insect and disease damage is, just as frequently we see tree and shrub injury that is caused by a weather event, site condition or other factor. These are known as "abiotic" disorders i.e. injuries caused by something non-living, whereas "biotic" problems are caused by an animal, insect, pathogen or other organism.
It is important to be able to determine whether a problem is biotic or abiotic, to have any hope of finding a solution.