Trees which have not had the benefits of the services above frequently develop yellowing in the canopy. Generally, this is the absence of chlorophyll caused by micronutrient deficiencies. This is called chlorosis, and it results in significantly reduced energy production depriving the tree of the resources it needs to grow and maintain its health and resist insects and diseases. Chlorosis is correctable with trunk injection of the lacking micronutrients. Repetitive growing seasons under chlorotic conditions increasingly expose the tree to stress which typically results in the need for other extensive treatment or mitigation services.