POLYPHAGOUS SHOT HOLE BORER CAMPUS SURVEY
Mentor:Valerie Mellano, Professor and Chair, Plant Science Department, CSU Pomona, CSU Pomona
There has been a recent eruption of a pernicious insect known as the shot hole borer (Euwallacea fornicatus). This pest is a major threat to the agricultural stability in Southern California. A plant pathogenic fungus is vectored by the borer. The fungus, Fusarium sp., clogs the tree's vascular system, causing dieback in the outer branches. Avocados (Persea americana), one of California's premium crops, are threatened by the shot hole borer and associated fungus. The tree itself is not likely to survive the infestation. Other known hosts of the insect include Castor Bean (Ricinus communis), American Sweet Gum (Liquidambar styraciflua), California Sycamore (Plantanus racemosa), and Coast Live Oak (Quercus agrifolia); all of which are part of the campus flora and therefore, possible hosts. Our campus serves as a "living laboratory" for pests and disease issues that affect agriculture in Southern California. Being a major agricultural university, Cal Poly Pomona has several plots of trees prone to attack from the shot hole borer and its affiliated fungus. In order to discover the range and severity of potential infected plants, a campus survey needed to be conducted. Using the iPad application, ArcGIS by Esri, and the information from a compiled database of Cal Poly flora, I was able to specifically inspect trees of a known host range. I subsequently surveyed the Cal Poly campus in search of symptoms of the fungus and beetle on proven hosts. The results reveled two main areas where the host population is over 50% infected. The severity of these infected trees range from borer holes and sugar volcanoes to signs of the Fusarium fungus.