It is most often associated with very wet conditions in the later stages of nut development. The shucks turn black. The kernel becomes discolored and is not eatable. In the southeast copper based fungicides are applied from the water stage to shuck split on a 10 day schedule. This disorder is associated with a fungus which attacks the nuts in the latter part of July and August.
Shucks turn black rapidly and drop soon after.
Lesions are black, sunken, and shiny. When infected nuts are cut open, the liquid in the kernel has turned brown. This can be controlled with foliar sprays of a fungicide applied when the pecans begin to fill. Small swellings are found on the rootlets. Infected trees develop severe zinc deficiency symptoms.