Articularia leaf mold caused by the fungus _Articularia quercina_ (PK)
Hoehn is a disease of minor occurrence and importance. The disease
occurs most commonly following rainy periods and in areas of high
relative humidity in the leaves of trees of poor vigor.
The fungus produces on the lower surfaces of the leaves a conspicuous
growth of white tufts which contain masses of spores, Figure 6.
[Illustration: Figure 6. Articularia leaf mold fungus, showing white
tufts on lower leaf surfaces of pecan leaflets.]
_Control._—Articularia leaf mold does not occur in trees or in orchards
which have been sprayed for disease control.
A single application of fungicide such as zineb at 2 pounds per 100
gallons of water when the disease is first detected is usually
sufficient to control Articularia leaf mold disease.