Susseptible elms include American, Chinese, Dutch, Scotch, slippery, and winged varieties,
and disease severity may vary from tree to tree of the same variety.
Leaves and twigs with black spot begin with small, white to gray to yellow irregular
spots which later become "tarlike" black spots. Leaves may turn yellow and exhibit
premature defoliation. Usually the disease becomes prevalent in the fall about the
time of normal leaf drop and little damage is done to the tree.
Infected twigs and dead limbs should be pruned and destroyed (buried or burned). Protective
sprays are available and should be applied in the spring as leaves unfold. Please
contact your local county extension office for current information.