Sudden Oak Death Pathogen Is Identified In Missouri

Plant experts say the SOD pathogen arrived in Midwest states on infected rhododendron plants. The affected rhododendron plants were shipped to local retail stores in Missouri, Illinois, and Kansas.

State agricultural experts also identified more than 100 plants infected with P. ramorum in over 100 nurseries across the mid-state region of Missouri. Stores and nurseries removed the unsold rhododendrons from their stock once the pathogen was identified.

In oak tree species, including red oak, P. ramorum causes SOD by allowing sapwood-decay fungi to enter the trees. Because the heartwood of oak trees degrades as the plants age, strong sapwood is vital to keep oak trees standing tall. When both the sapwood and heartwood are decayed, oak trees are at risk of collapse because their structural integrity is weakened.

Experts fear the introduction of P. ramorum in Missouri and other Midwest states could cause issues with SOD in the region. There could be significant oak-tree loss in Missouri and other affected states if the pathogen spreads to forested areas or the nearby Appalachian Mountains.

Plant species that tested positive for P. ramorum in the Midwest include the following:

To stop the spread of SOD, destroy and remove new ornamental plants you suspect are infected with P. ramorum. To destroy the plants, experts recommend double-bagging the plants with the root ball intact. Dispose of plants with the trash. Never mulch or compost SOD-infected plants, since the pathogen can live on in the soil.

Burning infected plants is another option to stop the spread of P. ramorum, but any unburnt plant material can harbor the disease. Ensure infected plants are completely destroyed by the heat of the fire.

The P. ramorum pathogen thrives and spreads by spores from plant-to-plant during wet weather. Since over 100 plants in the forest can be hosts to P. ramorum, once the pathogen is present in woodlands, oak trees become vulnerable to SOD.

Limit your walks and drives through woodlands during wet weather to limit the spread of SOD and other pathogens. Since P. ramorum can spread via items including shoes, clothing, and pet hair, enter woodlands only during dry days. The spread of the SOD pathogen is less of a risk when soil and organic matter in woodlands aren't soaked with rain.

Your tree service professional is a great ally in your quest to have healthy oak trees. Consult a qualified tree service if you suspect any of your oaks and ornamental plants are infested with the SOD pathogen.

If you think you've purchased an infected rhododendron or your oak trees seem sickly, contact us at Country Tree Service right away for expert advice, tree care, and tree-removal services.