I am finding black, leaking areas on my sabal palms. What could be wrong?
I had to schedule a site visit to your house for this problem. It is Thielaviopsis trunk rot which is caused by the fungus Thielaviopsis paradoxa. Due to this disease, the palm trunk either collapses on itself or the canopy suddenly falls off the trunk, often without warning. One of the palms was already showing areas where it was spongy.
The palm canopy may appear healthy prior to collapse but the top of your palm is brown and totally dead. Except for stem or trunk bleeding, there may be no symptoms prior to collapse of the palm.
Only fresh trunk wounds will become infected by the fungus, so disease management includes limiting man-made wounds to the palm trunk, especially the upper third of the trunk. This often occurs when the “boots” are removed, the trunk is wounded and the disease has a perfect opportunity to enter. If “boots” are removed, it is critical to clean tools between removal. Boots are the lower portion of the frond stem or petiole.
There are no methods to prevent or cure this disease. The palm should be removed immediately, and the diseased trunk portion destroyed but not recycled.
For more complete information check out the University of Florida publication: http://edis.ifas.ufl.edu/pp143