Sudden oak death in Indiana deemed worse than initially thought
P. ramorum symptoms on Rhododendron in central California
Photo courtesy of Joseph O’Brien, USDA Forest Service,

Sudden oak death in Indiana deemed worse than initially thought

More than 88 stores throughout the state received the infected varieties of rhododendrons.


From the Indianapolis Star:

After a dangerous disease that could prove fatal to Indiana's oak trees was discovered in the state last week, officials now are saying that the problem is "bigger than [they] realized."

The fungal pathogen called sudden oak death was detected in several varieties of rhododendrons being sold in what was first believed to be in about 30 stores across the state. That number has now tripled, and infested material was sent to more than 70 Walmarts and 18 Rural Kings in Indiana.

What's more, it's been discovered that the infected plants were delivered to nine other states, according to Megan Abraham, director of the Indiana Department of Natural Resources’ (IDNR) Division of Entomology & Plant Pathology.

You can read more about sudden oak death damaging Indiana’s oak trees here.

Sudden oak death is a disease that is capable of rapidly killing certain species of oaks, but more than 100 plant species are susceptible. It was first identified in California, in 1995. Two years earlier it was identified in Germany and the Netherlands, killing rhododendron. Because the pathogen originally infected and killed tanoaks, an undesirable, understory scrub tree, it generated little interest until other, more desirable oaks species began dying, according to the Purdue University Landscape Report.

According to the IDNR, people in Indiana that have ordered plant genera known to be susceptible to Sudden Oak Death from any California nursery are prohibited from receiving that material until the California nursery has been inspected and shown to be free from the Sudden Oak Death pathogen by the USDA APHIS PPQ or California Department of Food and Agriculture using the federal inspection protocols.

If any plant material from California has already been received, the IDNR states that you must do two things with it:

  • Remove that material and any intermingled plants from the sale.
  • Have the IDNR inspect the material and release it.