Australian leaf beetle spreading across eucalyptus canopy

July 28, 2026Los Angeles Plain

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(Paropsis atomaria), a small spotted leaf beetle from Australia, has been quietly spreading across the west side of the basin since late February. In just the past week alone, there have been five new sightings ranging from Kenneth Hahn State Recreation Area through Culver City and up toward UCLA — 67 records in total since the beetle first appeared. In its native range, this beetle feeds on eucalyptus foliage and can defoliate trees when populations build.

The concern here is geography and history. Eucalyptus was planted by the millions across Los Angeles over the past century and a half, lining streets, filling parks, and covering hillsides from the coast to the foothills — creating a continuous, connected food source across an enormous urban canopy. A beetle that specializes on eucalyptus has essentially inherited an ideal landscape. Whether this establishes into something that those trees here will struggle with, or stays below the threshold of serious damage, remains an open question — one worth watching as summer peak activity continues.

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