Beetle Trappers on the Hunt

Agricultural inspectors discovered a second palm tree infested with the destructive red palm weevil in North Laguna.

But since traps were set last month near the first ever infestation of the exotic pest in the U.S., no more of the insects have turned up beyond the two dying palms, and the hunt to exterminate them has downshifted from daily to weekly checkups, experts say.

For now it would seem, the bugs are on the run or at least laying low.

This may reflect the season rather than the extent of the infestation; fall and winter are low activity times for the insects, which flourish with warmer temperatures come spring.

“You really do have to allow trapping to get through at least one of the high activity seasons for the pest before you can make any guesses about the extent of infestation,” said Jay Van Rein, a spokesman for the state Department of Food and Agriculture.

In the meantime, local, state and federal agriculture officials are taking precautions and convened a meeting recently in Laguna to train landscapers and gardeners about infestation symptoms and pest control measures.

Victor Hallstead, the city’s deputy public works director, whose responsibility includes maintaining city trees, was part of the meeting’s capacity crowd. Hallstead said his staff has been trained on how to detect the pests.

If the red palm weevil spreads, it could damage the state’s date crop, valued at $30 million annually, according to UC Riverside’s Center for Invasive Species Research. The beetles, which are native to Southeast Asia but also found in Africa, the Middle East, Europe and the Caribbean, have caused extensive damage to palm tree growers in those areas.

About 250 traps remain deployed in North Laguna as part of a detection program that includes visual surveys of the area, as experts are still trying to determine the extent of the infestation.

“The insects really slow down over winter and resume higher activity in spring and summer. So it’s a matter of following temperature models,” said Van Rein.

Last week, state agriculture workers removed the infested tree stump, which was examined by scientists before being buried in a landfill, Van Rein said.

A local tree service first reported the weevil after removing a tree in early October. That tree was cut into pieces, double bagged in heavy plastic and buried under six feet of soil and trash in a Brea landfill. The stump found more recently met a similar end.

Nick Nisson, the county’s agricultural entomologist, said there is no evidence of infestations in other areas, and current efforts remain focused on the area immediately around the tree in North Laguna.

“Traps are only out in a grid pattern from the original finds. If it shows up anywhere else, traps would be placed in a grid around that find. All other efforts are visual,” he said.

Eradication efforts partly rely on training gardeners and landscapers what to look for. The insects have a long, slender snout and bore tunnels into tree trunks to deposit their larvae. One of the larger beetles in Southern California, the red palm weevil is a strong flyer with a range of more than four miles from its hatch site. Infested trees may exhibit holes or tunnels anywhere on the tree, “gnawing” sounds caused by larvae feeding inside, viscous fluids oozing from tunnels, chewed plant material, a distinctive “fermented” odor and dead adult weevils, according to UC Riverside’s Center for Invasive Species Research.

The agriculture department’s pest hotline is 800 491-1899.

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