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removal of exposed citrus trees because a judge stopped tree removal in response to homeowner lawsuits using standards in effect at the time. Homeowners were opposed to removal of trees that were not infected without evidence that they could be sources of inoculum. During the moratorium, the bacteria quickly spread and additional sites were discovered in southwest Florida. During this 12-month study period, the 1,900 ft rule (580 meter radius) was created which expanded the quarantine to 129,500 h (500 mi2) with a program budget of $9.5 million. By 2000, the Persian lime industry in south Florida had been destroyed (Schubert et al., 2001).

2004: The three hurricanes and a tropical storm that crossed the Florida peninsula dispersed the pathogen even further across the state (Irey et al., 2006a; Gottwald and Irey, 2007); resulting in the establishment of new infections at substantial distances from the known existing infections. Survey and eradication efforts by the FDACS and USDA-APHIS became even more intense to eliminate new outbreaks before the next hurricane season.

The FDACS and USDA-APHIS simultaneously employed the following survey protocols: the sentinel grove survey (based on sentinel commercial blocks of susceptible cultivars), the targeted grove survey (based on meteorological data that used a GIS-weather model to predict the direction of disease spread due to hurricanes), the delimiting grove survey (which was performed once new infections were discovered) and the self survey (performed by the grower). Production managers and other workers that are in contact with commercial citrus on a daily basis were trained by a joint University of Florida and FDACS-DPI program to search for, recognize, and report suspicious symptoms to FDACS-DPI or USDA-APHIS inspectors for confirmation.

Not all citrus canker-infected trees detected in 2004 had been removed by the time the first hurricane (Hurricane Wilma) hit the Florida peninsula in October 2005. Of the 80,000 acres of commercial citrus identified as affected after the 2004 season, 32,000 acres remained even with the removal of 120,000 trees per week. It was estimated that an additional 168,000 to 220,000 acres of commercial citrus would have to be destroyed after the 2005 hurricane season under the 1900-foot protocol. At this point in time, the annual federal appropriation to maintain the program was $36 million. Eradication costs significantly increased from $10 million in 1996 to $50 million in 1999. In 2000, program costs escalated to $145 million. A panel of USDA scientists and global experts in citrus diseases conferred and concluded that the disease was now so widely distributed that eradication was not feasible.

On January 11, 2006 the USDA issued a press release stating that it would discontinue all efforts to eradicate canker. Subsequently, the Florida House of Representatives decided to halt the eradication campaign and repeal the 1900-foot protocol on May 3, 2006. However, because of the value of the fresh fruit industry and not every citrus production area in Florida was severely infected, there was still considerable support from the production industry to continue with a revised management program. Hence, the concept of a State-Federal-Commercial Industry Citrus Health Response Plan was launched. It is based on best management practices, living with the disease while minimizing production losses, and the implementation of a quarantine that prohibits the movement of fruit from known-infected areas of the state to non-infected areas and to other citrus-producing states. This plan has evolved into a National program, the Citrus Health Response Program, and is administered by the USDA-APHIS. USDA-APHIS has recently lifted the quarantine on Florida fresh fruit after findings that commercial fruit is not an important means of spread of the disease, thus allowing growers more flexibility in marketing their fruit.



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