Tree root systems are naturally very shallow and widespread. As urban trees grow, root development is hindered by restricted spaces and disturbed soils.
It is estimated that over 80 percent of all landscape problems originate below ground, but even basic knowledge about urban soils and root management is lacking. Insufficient rooting space, poor soil drainage, soil compaction, roots severed during transplanting or construction, and root disease are among the numerous below-ground causes of tree problems that need to be better understood. The goal of tree root research is to foster improved practices for planting and maintaining city trees.
Root research at The Morton Arboretum includes investigations on alteration of root architecture resulting from nursery production practices, how to improve root structure in urban soils, root management, and the effects of fertilization on root development.
The Arboretum's leading researcher on root biology and management is Gary Watson.
He also is the author, with E.B. Himelick, of The Practical Science of Planting Trees (International Society of Arboriculture, 250 pages, 2013).