Carry out regular inspections of trees you own, anytime of year whether in leaf or not. Inspections following severe weather should also be carried out.
A systematic approach is needed, always check the main trunk, root flare, stems and branch unions for any structural defects or signs of structural failure.
Observing conditions in the upper canopy of trees can be made more easily with a digital camera or video recorder. Trees in poor condition tend to have dead branches and twigs, off color leaves and possible defects on main supporting limbs or stems. Trees in poor condition can also have full healthy looking crowns that show now sign of the decay in the root system.
Sometimes the problem is easily explained, sometimes the problem has gone on so long unnoticed the tree cannot be helped. Regular inspections can spot the causes long before they become a problem and long enough for a plant and tree health care program to take effect.
Information gathered on your trees and shrubs can ensure the correct decisions are made to meet the trees needs and the sites goals.