Palms that take up excessive amounts of water may have trunks with deep longitudinal splits. These trunks will often appear waterlogged and may be covered with mosses, lichens, algae, and other epiphytes (Fig.1).
This trunk splitting is believed to be due to greater water uptake and expansion of the soft-walled parenchyma cells that predominate in the central portion of most palm stems than in the peripheral tissue that is dominated by rather rigid vascular and fiber cells.
This problem is most common in areas that typically receive high rainfall but can also occur in drier areas in response to extended wet weather.
The occurrence of this disorder cannot be predicted, prevented, or treated. The structural strength of a palm is usually not significantly weakened by minor stem cracking, but cracks extending half-way through or more could reduce trunk strength.