JEFFERSON CITY, MO — Missouri Officials say some rhododendron plants in retail nurseries are diseased with ramorum blight.

The plants were shipped to Wal-Mart and Rural King stores throughout Missouri, as well as the Springfield Home Depot, Stark Bros. Nursery Garden Center, and Fort Leonard Wood PX.

The Missouri Department of Agriculture and USDA Animal and Plant Inspection Service says anyone who bought rhododendrons or lilac plants labeled Park Hill Plants between March and June of this year should dispose of the plants immediately.

The department says anyone who is not sure of their plants variety should look for wilting or browning leaves, leaf spots and twig dieback. If you notice these symptoms, call the Department’s Plant Pest Control team at 573-751-5505 to start the disposal process.

Infected plants need to be disposed of immediately to stop the disease from spreading.

The agriculture department says plants may be destroyed by burning, deep burial, or by double-bagging the plant with its root ball in heavy duty trash bags for disposal in a sanitary landfill (where allowable). They say the infected plants should not be mulched, composted, or disposed in yard waste. Garden tools used to dig up any infected plants should be sanitized before they are used again.

Ramorum blight is also known as ‘sudden oak death’ when it infects oak trees. The department says the disease is caused by a fungus-like pathogen known as Phytophthora ramorum. 

The department says the plant disease has caused death in some types of oak trees in California and Oregon, but has not made itself in the Midwest. The disease has a host list of over 100 species of trees and shrubs. The department says they have went to over 113 retail stores with USDA-APHIS to take samples and place potential diseased plants under quarantine.

USDA-APHIS claims to have worked with Wal-Mart to form a voluntary recall of the infected plants, while other locations have isolated or destroyed infected plants.

The departments say they traced the shipment of the rhododendrons to Park Hills Plants in Oklahoma and they may have originated from nurseries in Washington State and Canada. Plant varieties found were shipped to at least 18 states.

Specific varieties of rhododendrons that have tested positive in destination states include:

  • Cat Cunningham Blush
  • Firestorm
  • Holden
  • Nova Zembla
  • Percy Wiseman
  • Roseum Elegans
  • Wojnars Purple.

Specific varieties of lilac that have tested positive in destination states include:

  • Common Purple
  • Persian Lime