Palm Tree Killing Bug Found in Laguna Beach

A pest, which the California Department of Food & Agriculture (CDFA) considers to be “the world’s worst pest of palm trees,” has been found in the Laguna Beach area, state officials announced on October 18. They said this is the first-ever detection of the red palm weevil (Rhynchophorus ferrugineus) in the United States.

The Southeast Asia native insect has spread throughout parts of the world, including Africa, the Middle East, Europe and Oceania. The closest confirmed detections to the United States was in the Dutch Antilles and in Aruba in 2009.

A landscape contractor in the Laguna Beach area first reported the red palm weevil to authorities, prompting local, state and federal officials to confirm its existence, conduct a door-to-door survey and set 250 traps to determine if an actual “infestation” exists. Others are encouraged to report suspect infestations by calling the CDFA Pest Hotline at 1-800-491-1899.

Although most all palm trees are non-native to California, the palm tree industry generates approximately $70 million in sales annually and date palm growers, most notably found in the Coachella Valley, harvest $30 million worth each year.

Here’s how devastating the pest can be, detailed by the CDFA:

Female red palm weevils bore into a palm tree to form a hole into which they lay eggs. Each female may lay an average of 250 eggs, which take about three days to hatch. Larvae emerge and tunnel toward the interior of the tree, inhibiting the tree’s ability to transport water and nutrients upward to the crown. After about two months of feeding, larvae pupate inside the tree for an average of three weeks before the reddish-brown adults emerge. Adults live for two to three months, during which time they feed on palms, mate multiple times and lay eggs.

Adult weevils are considered strong fliers, venturing more than a half-mile in search of host trees. With repeated flights over three to five days, weevils are reportedly capable of traveling nearly four-and-a-half miles from their hatch site. They are attracted to dying or damaged palms, but can also attack undamaged host trees. Symptoms of the weevil and the larval entry holes are often difficult to detect because the entry sites can be covered with offshoots and tree fibers. Careful inspection of infested palms may show holes in the crown or trunk, possibly along with oozing brown liquid and chewed fibers. In heavily infested trees, fallen pupal cases and dead adult weevils may be found around the base of the tree.