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• In 2004, the National Academy of Sciences (NAS) released their independent scientific review of the Pierces Disease program. • In 2005, GWSS egg parasitoids, Gonatocerus morrilli and Anagrus epos, were released and the Nursery Treatment Pilot Program began; once again the wine grape growers demonstrated their continued support for the program by overwhelmingly voting to continue the wine grape assessment for PD research. • In 2007 there were 60,600 shipments of nursery stock from infested areas to un-infested areas that were inspected, and statewide no new infestations of GWSS were found and 35 counties were verified as being free of GWSS infestation. • In 2008 the Nursery Approved Treatment Program was implemented for nurseries in GWSS-infested areas and full-time staffed border inspection stations increased from two to 16. GWSS infestations in the Beach Line area (Imperial County) were declared eradicated. • In 2009, Blossom Hill area (Santa Clara County) and the Foothill Farms area (Sacramento County GWSS infestation were declared eradicated. SB2 passed and extended and expanded the current Pierce’s Disease Program if growers approved a referendum on the research-oriented program in 2010. • In 2010 the referendum was approved, extending the PD Program to do research and outreach on other invasive pests that affect wine grapes. Economic Impacts: The cost of the GWSS to the nursery industry alone easily adds up to millions of dollars lost because of the high labor costs to inspect 100% of plants being shipped from southern California to northern California, costs of pest management programs to control GWSS in their operations and eradicate it from all plants being shipped, paper work required to document and comply with the regulations governing the movement of nursery stock, and the innumerable hours spent by dedicated nursery owners who served on committees to help shape regulations and identify research needed to keep plants moving from southern California to northern California. Conclusion: Reviewing the CDFA pest rating system, nursery growers should note that a “C”rated organism is subject to no state enforced action except to provide for pest cleanliness in nurseries. Considering the state budget crisis and the lack of an organized nursery industry, industry funding, and political influence, it is obvious why pests like GWSS can become such an enormous threat and cost to the industry.

Myoporum Thrips (Klabothrips myopori) The Myoporum thrips was first observed in southern California in Orange County in 2005. The CDFA quickly assigned a Q rating for this thrips. At first, there was an attempt to eradicate the pest in landscape plantings in San Diego County in 2006 using imidacloprid. However, time and funding lacked and resources were diverted to infestations of more serious invasive pests like Diaprepes. Therefore, landscape plantings of Myoporum along coastal California became more heavily infested with thrips over time, reducing the aesthetic quality of the plantings and tree death is now a common occurrence. The range of this species in California continued to expand along coastal CA to San Jose, Santa Clara County, CA on 22 August 2007. No further efforts to eradicate this pest were attempted. We have conducted a number of trials against the pest in the last couple of years in the hopes of identifying products that may be used in management of this pest. In addition, we have determined the life cycle of the insect at 30ºC. A figure with some of our recent trial results and some of our key findings are provided below. Key findings • Damage (Figure 1) to terminal growth can occur from a single thrips feeding on the terminal. The more thrips that are present the more quickly the damage is evident. • As with other thrips, including the closely related Cuban Laurel Thrips, there are two nymphal stages and two pupal stages prior to the adult stage. All early stages are white to green in color and the adult is black. • Eggs and all stages of thrips can be found in the twisted deformed terminal growth. • Twisted gall-like new growth protects the immatures from the environment. • The minute pirate bug, a natural enemy of the thrips, is commonly found in our samples. • This thrips is well protected from pesticide contact, so making the toxicant available at the feeding site is effective. • Systemic products are most effective at the highest recommended rates. Preventative Treatments: New growth can be protected with continuous applications of common pesticides such as the pyrethroids, carbamates and organophosphates. They should be applied by label directions and reapplied according to the pest management guidelines on the label. In addition to the broad-spectrum pesticides, terminal growth can be protected for longer periods of time by applying the neonicotinoids as a drench application. Effects CAPCA Adviser 


December CAPCA Adviser  

December CAPCA Adviser