Transplant shock is fairly common in newly transplanted trees. The Arboretum researchers have found that a tree can lose as much as 90% of its root system when it is removed from the nursery. This causes a great deal of stress on the plant as it is tries to reestablish itself. Research has shown that approximately one year of recovery is needed for every inch of tree diameter. Starting a regular plant maintenance and inspection program to head-off problems early, and providing good after-care will help maintain the health and vigor of your newly planted trees and shrubs.