Typical mortality spiral for red oaks. If the stress can be removed from our city tree, it may recover. Typically, however, other problems compound the situation. Periods of drought intensify the soil and root problems. The tree is wounded by a car.
Insects attack the trunk.
Energy levels are depleted further. The tree begins to decline and, if stress continues, the tree dies. The spring has stretched beyond its limits. Such a spiral can begin at any age and may take several years to run full course. The objective of comprehensive, long-term tree care programs is to use our knowledge of tree systems to prevent or minimize stress and avoid mortality spirals.