Often irreplaceable, mature shade trees are a landscapes greatest asset but unfortunately are the least resilient to both man-made and natural stresses. Various factors are detrimental to a mature trees health, the biggest being nearby construction that damages the root zone. Generally, damage is irreversible, making a preventive management plan the most effective in their preservation. Pruning is essential to promote better health and structure while removing hazardous, dead and objectionable limbs. Soil treatments such as the introduction of compost, aeration and organic fertilizers have also proven effective in preserving mature trees or reinvigorating declining and stressed trees.