This often-fatal palm disease is caused by a fungus (Phytophthora palmivora) that enters the palm through wounds or other openings. The spores can also be washed down into the palm bud by heavy rains. Once infected, palms may die within a short time. Most severe bud rot occurs from spring to fall.

This disease is caused by a fungus (Gliocladium vermoeseni) that infects parlor palm (Chamaedorea elegans) and some other palms. The fungus produces large numbers of pink spores on infected leaf bases and in an infected bud area. Air currents carry these spores, which will infect other palms if the leaves are wet. The fungus kills the leaves and may invade the central bud and kill it, too. Gliocladium rot is favored by low temperatures.

This serious palm disease is caused by bacteria-like organisms called phytoplasmas, which are carried from palm to palm by a planthopper (Myndus crudus), a tiny sucking insect related to leafhoppers. Planthoppers feed on fronds, especially the newly emerging ones, and are difficult to detect and control. Coconut palms and many other palms are susceptible.

Several species of this common insect feed on palms. Mealybugs damage plants by sucking sap, causing leaf distortion and death. The adult female mealybug may produce live young or may lay eggs in a white, fluffy mass of wax. The immature mealybugs, called nymphs, crawl all over the plant and onto nearby plants. Soon after they begin to feed, they produce white, waxy filaments that cover their bodies, giving them a cottony appearance. As they mature, they become less mobile. Mealybugs cannot digest all the sugar in the sap, and they excrete the excess in a fluid called honeydew, which coats the leaflets and may drop onto surfaces below the plant.

Rhynchophorus cruentatus This weevil is a Florida native whose primary food is cabbage palm (Sabal palmetto), but it will feed on saw palmettos (Serenoa repens), Canary Island date palms (Phoenix canariensis), Mexican washington palms (Washingtonia robusta), royal palms (Roystonea), Bismark palms (Bismarckia noblis) coconut palms (Cocos nucifera) and some other palms as well. It is attracted to damaged or dying palms. The adults are black and red, or all black, beetles up to 11/4 inches long and have long snouts. Their young are legless yellow grubs to 11/2 inches long. They feed on the new leaf tissue around the central bud, killing the leaves and eventually, the entire plant. Adults fly actively, and are most noticeable in late spring and early summer. Palms under stress, including newly planted palms, are at the greatest risk from palmetto weevils.

Several different types of scale insects attack palms. Some types can infest many different plants. Scales hatch from eggs. The young, called crawlers, are small (about 1/10 inch) and soft bodied and move about on the plant and onto other plants. After moving about for a short time, they insert their mouthparts into the plant, feeding on the sap. The legs disappear, and the scales remain in the same place for the rest of their lives. Some develop a soft covering, others a hard covering. Some species of scales are unable to digest all the sugar in the plant sap, and they excrete the excess in a fluid called honeydew, which may cover the fronds or drip onto surfaces below.

These mites, related to spiders, are major pests of many houseplants, including palms. They cause damage by sucking sap from the undersides of leaflets. As a result of their feeding, chlorophyll disappears, causing the stippled appearance. Spider mite webbing traps cast-off skins and debris, making the plant messy. Under warm, dry conditions, mites can build up to tremendous numbers.