More information about plum pox outbreaks in the U.S.
Have trees in the U.S. been infected?
In September 1999, PPV was found in Adams County, Pennsylvania. Since then, it has also been found in Franklin, York and Cumberland counties in Pennsylvania. To ensure that the PPV was eradicated, more than 1,600 acres of commercial orchards and homeowner trees had to be destroyed at a cost of over $40 million.
In July 2006, USDA confirmed the presence of plum pox virus in New York within five miles of plum pox eradication zones in Canada (The virus was discovered in Canada in 2000.) Plum pox virus was also identified in Michigan in August 2006.
In May 2007, USDA declared an extraordinary emergency in Michigan and New York due to plum pox virus and provided funds to assist with eradication expenses.
Where did plum pox originate and where have infected trees been
The disease was originally found in Bulgaria in 1915 and has spread throughout Europe where it has destroyed well over 100 million stone fruit trees. In the past decade, plum pox has spread from Europe to India, Egypt, Lebanon, the Azores, Chile, and most recently, Canada, Argentina, China, and the state of Pennsylvania.
How did the virus get here?
How the virus spread to Pennsylvania is unknown, but it is most likely to have been through the introduction of infected material.
How are trees infected?
PPV is spread from tree to tree by aphids, which are small insects that feed on sap, and through grafting infected budwood onto non-infected plants.
Are other trees susceptible to the virus?
More than 40 Prunus species are now known to be susceptible to this virus. These include trees native to North American woodlands such as wild black cherry, a valuable lumber species, wild red cherry, sand cherry, choke cherry, big-tree plum, beach plum, chickasaw plum, American plum, and popular flowering Prunus ornamentals such as flowering cherry and dwarf flowering almond.
Other stone fruit trees, including peach, nectarine, plum, apricot and cherries, are also susceptible.