The sago palm is not a palm at all, but a cycad and more closely related to the conifer than the palm. Consequently, the sago palm requires different growing conditions. While the tropical palm enjoys moist soils, the sago palm needs drier conditions. In fact, high soil moisture levels and other stress may cause this normally impervious plant to develop a few diseases.
The fungus that causes heart rot enters compromised sago palm trees through punctures or wounds in its bark that expose bare wood. The fungus then feeds on the non-living heart wood in the interior of the trunk. Sago palms with a significant infection will have large mushrooms or fungus conks growing at their base. There are no chemical treatments prescribed for heart rot. But healthy sago palms are able to compartmentalize the infected heart wood tissue and grow around it.
Ganoderma Butt Rot
Ganoderma butt rot is a lethal fungal diseases that can enter compromised sago palm trees through any wounds at its base. Once inside the tree, it will eat away at the wood in the center of the surface. As the fungus multiplies, it will feed closer to the surface, causing conks to grow. These conks look like white, spongy mushrooms and will grow, shelf-like, from the tree's trunk. There is no cure for ganoderma butt rot and by the time the conks are observed, it is too late to save the sago palm. It must be uprooted and destroyed. Do not replant in the area; the fungus lives in the soil.
Sago palms with frizzle top develop new leaves that quickly turn yellow and then brown on the ends as they develop. There can be several causes of frizzle top. One is soil with a pH above 6.5--sago palms need acidic soil. Too much moisture in the soil could also be rotting the roots and preventing the sago palm from absorbing sufficient nutrients. Or frizzle top can be caused by a lack of manganese. The manganese deficiency can be supplemented with a manganese spray and a fertilizer prescribed for use with palms.