DescriptionGanoderma zonatum on Cabbage Palm (7323737678).jpg
I believe this is Ganoderma zonatum, the pathogen that causes "butt-rot fungus" in palms. This is one of several basidiocarps on the base of a freshly-dead cabbage palm (Sabal palmetto). The fungus effects the lower portion of the trunks, hence the common name. There is no prevention or cure at this time.
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