Palms trees have adapted to their hot climate conditions in remarkable ways. They are drought-tolerant and can withstand exposure to salt air and soil. They thrive in sandy soils and often withstand hurricane winds. They are not immune to damage, however, and a number of environmental and disease conditions can cause palm trees to fall, creating risks to people and property.
Though palm trees grow in hurricane zones, they are usually able to withstand the 75 to 150 mile per hour winds that are generated during these storms. Sometimes, however, because of weak root structure or other problems, palm trees can topple over and fall to the ground. Fallen palm trees often litter the streets and property after the direct hit of hurricane force winds. Communities may attempt to right the trees and re-position them into the ground, bracing the trees until the root system re-establishes. Often, the trees cannot be saved, and new trees are planted in their place.
Palm trees can withstand temporary flooding, but extended periods of having their roots in water weaken their root system and cause the tree to decline and eventually die, according to University of Florida horticulturists Timothy K. Borschat and Jonathan H. Crane. Roots can become so waterlogged that they can collapse at the root line. Providing drainage for the tree by creating a run-off trench can help to prevent the root rot that can lead to the tree's decline.
Occasionally, during violent storms, lightning strikes the palm tree, causing the canopy to collapse and also causing splitting and bleeding of the trunk portion of the tree. Treatment by an experienced arborist can often save the tree, but sometimes, the damage is too great and the tree must be removed to prevent its collapse.
A fungus disease called Thielaviopsis trunk rot can affect palm trees, causing destruction of the wood of the trunk. It is caused by infection of a wound on the tree by the fungus, Thielaviopsis paradoxa. Infection can occur high in the tree, toppling the upper crown, or lower on the trunk, causing the entire tree to collapse. Treat the disease with an appropriate fungicide recommended by your local agricultural extension service. Prevent the spread of the fungus by sterilizing pruning equipment with a 25-percent chlorine bleach solution.
Palm trees can also fall after extensive damage from wood boring insects like termites. The insects can so undermine the tree's supporting structures that the wood collapses onto itself and the tree collapses. Careful monitoring of the tree and applying pesticide sprays when indicated help to prevent this problem.