The California Department of Food and Agriculture has released a lengthy analysis to address the “rising tide” of invasive pests entering the state — and according to the report, one seed-sized beetle is ravaging California’s landscape and likely costing billions of dollars in damages as a result.
The tiny but destructive invasive shot-hole borer poses an “imminent threat” to urban forests and home values throughout Southern California, particularly in Los Angeles County, interactive maps show. The two predominant species, the Kuroshio shot-hole borer and polyphagous shot-hole borer, are known to take over 60 different tree species in the state, and in 2024, a third species of ISHB was discovered as far north as Santa Cruz County.
The flying beetle, which carries a fungal pathogen that leads to a disease called Fusarium dieback, destroyed 120,000 willows in Southern California within just three years, a 2019 study found. After females spread the symbiotic fungus by boring into trunks and branches, the fungus blocks water from moving through the tree’s vascular system, ultimately killing it. Though pocks and stains are common symptoms among infected hosts, the fungus can also cause unsightly “sugar volcanoes” to appear on avocado trees…