Lucidus Root and Butt Rot
caused by Ganoderma lucidus

This disease is one of the most common root and butt rots of southern hardwoods. It has a wide host range including oaks, maples, hackberry, ash, sweetgum, locust, elm, mimosa, and willows, and is found throughout the South. Host trees normally decline for a variable period of time and then die.

Identification:

Fruiting bodies (conks) are produced at the butt or on exposed roots of affected trees. They have a stem, the tops are reddish to buff-colored, and the white undersurface is porous. Conks are tough, woody, and persistent.

Injury:

Affected trees usually show a rapid decline, evidenced by shortened twig growth, off-color foliage, dwarfed and sparce foliage, and branch dieback. The rotten roots are white and spongy, with black flecks or dark lines.

Biology and History:

This fungus invades trees stressed or wounded by a variety of agents, including fire, soil compaction, construction injury, vehicular damage, herbicide injury, and lawnmowers. Airborne spores contact the wounds and invade susceptible tissue, spreading up into the butt of the tree or down into the root system, or both. Colonization of healthy trees may also occur through root grafts or contacts with diseased roots.