Indiana DNR Warns of Oak Threat Found in Some Rhododendrons

The Indiana DNR says it confirmed Wednesday it has intercepted plants containing a fungal pathogen that kills oak trees. Inspectors from the DNR say the Sudden Oak Death (SOD) pathogen was detected in several varieties of rhododendrons sold at stores in South Bend, Columbus, Noblesville, Sullivan and Tippecanoe. Officials say large tracts of oaks on the West Coast have died and standing oak trees can be killed if affected rhododendrons are planted within about six-feet of the tree.

Additional information from the Indiana DNR:

SOD travels in more than a hundred species of host plant material. It causes some browning of the leaves in the host but does not kill it. For a list of those plants see the following https://www.aphis.usda.gov/plant_health/plant_pest_info/pram/downloads/pdf_files/usdaprlist.pdf
If you have purchased rhododendrons in the last four weeks in these communities, call 1-866-NO-EXOTIC (663-9684) or call the local county extension office at 1-888-EXT-INFO (1-888-398-4636) for instructions.
The DNR is destroying all rhododendrons from the source nursery, Park Hill Plants (Oklahoma), and any other host plants that were co-mingled with them. In addition, the DNR is quarantining the sale of four other common SOD host plants (viburnum, azalea, cameilia, and pieris) for further testing to determine if they contain SOD. Testing will determine if other species are infested and require destruction.
This is an ongoing investigation, and guidance could change as more information is gathered.
To learn more about SOD, see: https://www.aphis.usda.gov/aphis/ourfocus/planthealth/plant-pest-and-disease-programs/pests-and-diseases/phytophthora-ramorum/sod
To view all DNR news releases, please see dnr.IN.gov.