<P> Much of the research into disinfesting nurseries has focused on the voluntary best management practices (BMPs) that nurseries can implement to prevent P. ramorum's introduction into the nursery and movement from plant to plant . In 2008, a group of nursery industry organizations issued a list of BMPs that includes subsections on pest prevention / management, training, internal / external monitoring / audits, records / traceability, and documentation . The document includes such specific recommendations as "Avoid overhead irrigation of high - risk plants"; "After every crop rotation, disinfect propagation mist beds, sorting area, cutting benches, machines and tools to minimize the spread or introduction of pathogens"; and "Nursery personnel should attend one or more P. ramorum trainings conducted by qualified personnel or document self - training". </P> <P> Research on control of P. ramorum in nurseries has also focused on disinfesting irrigation water containing P. ramorum inoculum . Irrigation water can become infested from bay trees in the forest (if the irrigation source is a stream), from bay trees overhanging irrigation ponds, from runoff from infested forests, or from recirculated irrigation water . Experiments in Germany with three types of filters--slow sand filters, lava filters, and constructed wetlands--showed that the first two removed P. ramorum from the irrigation water completely, while 37% of the post-treatment water samples from the constructed wetland still contained P. ramorum . </P> <P> Since P. ramorum can persist for an undetermined period of time within the soil profile, management programs in nurseries should also deal with delineating the pathogen's distribution in nursery soil and eliminating it from infested areas . A variety of chemical options has been tested for soil disinfestation, including such chemicals as chloropicrin, metham sodium, iodomethane, and dazomet . Lab tests indicated that all of these chemicals were effective when applied to infested soil in glass jars . Additionally, tests on volunteer nurseries with infested soil demonstrated that dazomet (trade name Basamid) fumigation followed by a 14 - day tarping period successfully removed P. ramorum from the soil profile . Other soil disinfestation practices under investigation, or in which interest has been expressed, include steam sterilization, solarization, and paving of infested areas . </P> <P> One of the most important aspects of P. ramorum control involves interrupting the human - mediated movement of the pathogen by ensuring that infested materials do not move from location to location . While enforceable quarantines perform part of this function, basic cleanliness when working or recreating in infested areas is also important . In most cases, cleanliness practices involve ridding potentially infested surfaces--such as shoes, vehicles, and pets--of foliage and mud before leaving the infested area . The demands of implementing these practices become more complex when large numbers of people are working in infested areas, as in construction, timber harvesting, or wildfire suppression . The California Department of Forestry and Fire Protection and USDA Forest Service have implemented guidelines and mitigation requirements for the latter two situations; basic information about cleanliness in P. ramorum - infested areas can be found at the California Oak Mortality Task Force web site (www.suddenoakdeath.org) under the "Treatment and Management" section (subsection "Sanitation and Reducing Spread"). </P>

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