Tree health assessment
Pest and disease identification
Environmental influences

Tree health and seasonal variation characteristic (deciduous/semi deciduous or other) of a species requires separation. Sometimes they are intertwined.

Factors that can affect heath is injury inclusive of maintenance pruning and direct impact, age and longevity, growing and climatic conditions and changes within, development influences such as encroachment, change in natural soil hydrology and a plethora of other changes such as soil nutrient level, lightning strikes, poisoning both deliberate or otherwise. All factors causing injury and stress changes the demand for sugar allocation within the system and greatly exposes the tree to insect or pathogen attack (bacterial and fungal).