Spring 2004 Vol. 13, No. 1
INDIANA BANS CALIFORNIA
TREES, SHRUBS
by Department of Natural Resources Press Release
Roses, azaleas, rhododendron, camellias, and oaks among plants
listed. Just as the spring garden season is about to arrive in Indiana, so is concern about a serious plant disease. A fungus-like pathogen (Phytophthora ramorum) is responsible for Sudden Oak Death, a disease that has killed tens of thousands of oak trees in California.The California Department of Food and Agriculture found the pathogen in a 500-acre plant nursery and scientists are now concerned the sale of those plants around the country will also spread the disease. "While sudden oak death has not been found in Indiana, the potential threat of the disease is very serious," said State Entomologist Robert Waltz. "It has already devastated parts of the West Coast. In Indiana, if unchecked, the cost of this disease to nurseries, lumber companies, gardens, homeowners, our cities, our rural landscape and wildlife habitat would be felt for more than a generation."
Tuesday morning, DNR Director John Goss signed an emergency order banning the importation and sale of 31 specific types of trees and shrubs imported from California. Under the order, wholesale and retail outlets are not allowed to receive shipment of the banned plants if from California. The Indiana action comes on the heels of a federal quarantine from the U.S. Department of Agriculture aimed at nurseries in California. Waltz said that, because of the federal quarantine, there should be few of the banned plants in Indiana.
Hoosier nurseries and stores will be allowed to accept the restricted plants, even if from California, if the plants have been inspected and certified as disease-free by either the USDA or the California Department of Food and Agriculture. Wholesale and retail outlets that had already accepted shipments of plants from California prior to the federal or Indiana quarantine are required to segregate those plants from their remaining stock. They are then required to immediately notify the DNR that they have some of the banned California stock on hand. The DNR will send an inspector to examine the plants and, if free of the symptoms of the sudden oak death pathogen, the plants will be released for sale. If the symptoms are present, the stock will be held until laboratory tests can be completed. If the stock is free of the disease it will be released. If it is found to be infected it will be destroyed. Waltz estimates that about 600 nurseries and stores, out of the 4,000 in Indiana that sell trees and shrubs, routinely receive stock from California. Those stores and nurseries are being notified of the quarantine.
The pathogen is similar to one that appeared in the United States about 1904. That pathogen caused a disease that attacked chestnut trees and within 50 years had destroyed all 3.5 billion chestnut trees in the United States. Sudden Oak Death could cause a similar wholesale destruction of oak and other species of tree throughout the country, especially in the east and south. Waltz said the pathogen creates a spore that can be carried on plant leaves and twigs and, thereby, transported to new locations. If planted, the spores can be carried by the wind to other plants and infect those plants. The spores can also survive in the soil and be carried by people to new locations that way. "We are also asking Hoosier consumers to join us in trying to check the spread of this disease to Indiana," Waltz said. "People who visit an infected area of California must be very careful not to inadvertently bring the spores back to Indiana."
By issuing the quarantine, Indiana joins 11 other states and Canada that have also banned the importation of these plants from California. The other states with a quarantine are Mississippi, Washington, Alabama, Florida, Georgia, Delaware, Utah, Louisiana, West Virginia, Kentucky, and Tennessee. Waltz indicated that the pathogen that causes Sudden Oak Death disease is not harmful to humans, pets or livestock. It causes death in a limited number of species and genera of tree but can be carried by many more and do some damage to those plants.
Nursery operators or retail outlets with questions about Sudden Oak Death or plants that they may have in stock can call the DNR Division of Entomology and Plant Pathology at 317-232-4120. Those who want more information about Sudden Oak Death or a complete list of the banned plants can log on to the World Wide Web at: www.IN.gov/dnr/entomolo/