Dubbed the "FATHER OF MODERN ARBORICULTURE", Dr. Alex Shigo has spent most of his adult life studying, lecturing, dissecting and writing about trees. "A tree is much more than a chunk of dead wood," exclaims Shigo. "Trees are alive; they live all year 'round, not just for a short time in the summer." They work during the winter, too. Many people spend time on what goes wrong with a tree; I wanted to study what goes right."

• Pamphlet: Tree Hazards by Dr. Alex Shigo