Invasive Ambrosia Beetle Research Paper

The polyphagous shot hole borer (PSHB) problem, originated in Asian countries, shifted from a decayed and rotting host of trees in south east Asian countries to native, nursery, fruit, and landscape tree hosts in southern California and Israel. The boring beetle and tree host could exist mutually, however, the distinct symbiotic relationship between the invasive ambrosia beetle Euwallacea and the destructive fungi Fusarium poses a potential lethal threat to specific host trees, such as avocado trees, box elder, and coast live oak in California. The PSHB is generally associated with the ambrosia beetle. This beetle tends to target trees stressed from environmental conditions. In California, the western oak bark beetle and the ambrosia beetle …show more content…
An experiment to test these hypotheses measured boring beetle activity for 94 weeks from May 2002 until April 2004 against the four species of trees [4]. Groups of genotypes of trees were each treated with control conditions, irrigation, fertilization, and a combination of both irrigation and fertilization. Incidences of attack were recorded regularly using necrosis at the bore site as an indication of the presence or absence of attack. Necrosis was absent from the sycamore, sweetgum, and loblolly pine trees, thus no attacks were made against these. Insects collected from the traps were identified as predominantly Scolytidae. Among the 28 species captured--of which were predominantly identified as Scolytidae--more than 88 percent belonged to nine exotic species, which followed Coyle’s first hypothesis