Phytophthora ramorum
Trials of silvicultural methods for treating "P. ramorum" began in Humboldt County in northwest coastal California in 2006. The trials have taken place on a variety of infested properties both private and public and have generally focused on varying levels and kinds of host removal. The largest () and most replicated trials have involved removal of tanoak and bay laurel by chainsaw throughout the infested stand, both with and without subsequent underburning designed to eliminate small seedlings and infested leaf litter. Other treatments included host removal in a modified “shaded fuelbreak” design in which all bay laurel is removed, but not all tanoaks; bay and tanoak removal using herbicides; and removal of bay laurel alone. The results of these treatments are still being monitored, but repeated sampling has so far detected only very small amounts of "P. ramorum" in the soil or on vegetation in the treated sites.
Phytophthora ramorum
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.