Bug Blog

Insect Threats to Palo Verde Trees

Insect Threats to Palo Verde Trees

Palo verde trees are one of the staple plants that make up the desert landscape. Palo verdes are deciduous trees that have multiple trunks and are covered in spiny, green bark. They have a short flowering season, during which bright yellow flowers bloom all over the tree. Palo verde trees are not known for having a large number of diseases that threaten them, but it is often insect pests that put the tree’s health at risk. This iconic desert tree has to fend off a number of insect pests if it is going to survive in the harsh desert.

The palo verde root borer is one insect pest that poses a threat to the palo verde tree. These particular pests can cause severe diseases to infect palo verde trees. Other diseases that threaten the palo verde tree can be easily controlled, but there is no easy method to remove palo verde root borers. These root borers are actually the larval stage of the palo verde beetle, which can grow up to 3 ½ inches in length. These root borers use the palo verde tree’s roots as nutrients and a safe place for them to stay while they are growing from larvae to adults. In its larval stage, the palo verde root borer can actually grow as long as 5 inches while it’s attacking and eating the roots of the tree.

Another insect pest that poses a threat to the palo verde tree is the palo verde gall mite. These mites are quite tiny, and so are not easy to spot. However, the damage these little pests cause is quickly very visible. When these mites infest a palo verde tree they cause witches’ broom. This is when small, dense clusters of branches that tend to be a darker green color than normal branches develop on the outer parts of the tree, rising from an outer branch or the tip of a branch (this is where growth is most active). This disease causes mostly cosmetic damage and rarely results in the death of the tree, but can weaken its health. These clusters will grow larger and more numerous in number if the tree is infected with mites over a period of many years. Eventually, the infested branches do turn brown and die if not treated. Luckily, the disease can be controlled with regular pruning of the branches to remove the clusters of witches’ broom.

Have you ever seen a palo verde tree? Did it show signs of being infested by either of these pests?