Four Common Tree-Boring Insects Found in California

One of the problems property owners face in tree maintenance is insect infestation. Your trees can defend themselves against occasional insect attacks. However, repeated attacks can weaken their resistance and lead to an infestation, leaving your trees vulnerable to pathogens and bacteria. 

In this blog, we explore the most common tree-boring insects in California with the help of Folsom’s tree service company, Ace Tree Service.

Asian Citrus Psyllid

These tiny tree borer insects originated from Southeast Asia and were first discovered in the U.S. in 1998 and in California in 2008. Mature Asian citrus psyllids are roughly 4mm long, with black or brown heads and black-tipped antennae. Their brown bodies have darker brown spots. 

These bugs lay eggs in a line on the younger leaves of citrus trees. The eggs hatch into larvae, which feed on the leaves. Asian citrus psyllids attract various citrus trees, including grapefruit and orange trees. 

Infestation symptoms include pale green patches on the leaves, twig dieback, and tiny, underdeveloped fruits. Trees infested with these bugs usually die within five years. Regular and thorough spraying with insecticides can help avert an infestation. 

Emerald Ash Borer

The emerald ash borer (EAB) mainly attacks ash trees. They are prevalent in California and over 20 other states, including Arkansas, Colorado, Delaware, Kansas, and Massachusetts. 

In the initial stages of EAB infestation, you may notice cracks on the main branches in the tree canopy. Over time, the bark will develop 2-5-inch slits and D-shaped holes, and the canopy will start to thin. 

The most effective way to tree EAB infestation is to act as soon as you notice any symptoms. 

Asian Longhorned Beetles

The Asian Longhorned Beetle (ALB) attacks America’s hardwood trees and is prevalent in California, Ohio, New York, and Massachusetts.

Adult beetles are about 1-1.5 inches long with long antennae banded in white and black. Their black bodies have tiny white spots. Female beetles lay eggs under the tree bark that hatch into larvae within two weeks.

These larvae bore into the tree, feeding on the living tissue. In about a year, the larvae will become adults and chew their way out of the tree, leaving exit holes. Once out, the adults feed on the tree’s bark and leaves, eventually killing it. 

California Fivespined Ips

These tree-borer insects first became a big problem in California in the 1940s. They mainly attack pine trees, including white and sugar pines. 

An adult California fivespined ips is about 5mm long with a red-brown body. The males bore into the bark of healthy trees and release a chemical that attracts their female counterparts. 

The females enter the pine trees to mate with the males and lay eggs. After a while, the eggs hatch into larvae that bore more tunnels into the trees’ vascular tissues.

Contact Your Local Tree Experts for Assistance

If you need help dealing with tree boring insects and removing dead trees, the experts from Ace Tree Service are here for you. Contact us at (916) 934-3204 for a free estimate and to learn how a tree specialist can help.