Let clippings lie so they'll return nutrients to the soil. We have a king sago that has developed a white mold on the undersides of the leaves. Sagos are the favorite feeding sites of mealybugs, a scalelike insect that sucks juices from the stems. They are white and cottony like a mold and could be mistaken for a fungal problem. The white covering is waxy, making it difficult to control the insects.
Mealybugs usually cluster on the lower leaves and leaves protected from winds and rains.
Often removing the heavily infested leaves won't spoil the appearance of the plant and can eliminate most of the infestation. If the sago is near the pool, you want to avoid use of toxic pesticides. Possibly the remaining mealybugs could be washed off with a soapy water solution using a cloth or old toothbrush to loosen them from the plants. Though soapy water is considered nontoxic, it best to keep the water from entering the pool by spreading plastic sheeting under the plant. Tom MacCubbin is an urban horticulturist at the Orange County Cooperative Extension Service, a division of the Institute of Food and Agricultural Sciences at the University of Florida.