To properly manage insect, disease, and abiotic disorders we routinely learn about the need for proper identification of the plant material, the pest or pathogen, etc., and from here a variety of management options may be available.  The purpose of this program is to connect the most critical physiological processes in trees with various abiotic, pest, and disease issues to build understanding of why we manage certain problems the way we do.  For example, mineral deficiencies can lead to obvious visible defects in leaves like chlorosis.  Which physiological processes are impeded or limited by chlorotic leaves?  What other conditions can this lead to?  Why is this important to the tree?  Beyond these questions, when we manage a problem like chlorosis what treatments are available to arborists and how does the tree's physiology relate to these practices?  The basic structure and physiological functions of the leaves, stems, and roots will be described along with a variety of examples of how these processes are influenced by stress agents and pests.  Woven throughout are examples of how our arboricultural practices relate to those same functions.  This is a good review of tree physiology for arborists of all levels.