Picture of the Week
September 21, 2020
Sooty Mold on Beech
Gail Ruhl, Plant Disease Diagnostician
The sponge-like growth on this branch and leaf collected from a beech tree
is an unusual type of sooty mold. Sooty molds are entirely superficial
saprophytes that get their nourishment from honeydew-like secretions from
insects such as aphids, soft scale, and mealy bugs. The beech tree was
infested with a woolly aphid species and thus this specific sooty mold
fungus, known as Scorias spongiosa, is feeding on the honey dew excrement
from the woolly aphid.
Click image to enlarge
