Protecting Your Trees From Sudden Oak Death

Trees provide so much value in both residential and commercial properties. It’s easy to spend time enjoying the shade of our foundation trees and admiring the height and beauty of mature trees that stand majestically in the California sky.

While trees are planted for their beauty and enjoyment, it’s imperative that you take some time to put together a preventive health program for your trees. Healthy trees are the best offense against a slew of pests and diseases that target your trees. One disease that can threaten your oak trees is Phytophthora ramorum, a plant pathogen known to cause the disease sudden oak death (SOD).

This voracious disease is an invasive plant pathogen. When the pathogen strikes susceptible trees – including tanoak, coast live oak, California black oak, Shreve’s oak and canyon live oak – a death of the tree is likely. It currently occurs in coastal California counties from Monterey to Humboldt and in a small area of southwest Oregon. The disease is estimated to have killed more than 1 million oak, and tanoak trees over the last 10 years.

Sudden Oak Death Symptoms

Infections on oak trees earned the name sudden oak death because of the rapid (2- to 4-week) browning of leaves without a prolonged period of decline. The tree’s foliage may appear healthy until right before it turns brown or the leaves may pale several weeks before turning brown.

Diagnosis of infected trees and proper disposal of infected wood and other material is essential to help limit the spread of the disease. The key is a preventive approach to protecting trees at risk before they become infested. Ned Patchett Consulting, local tree care specialists, shares the following warning signs to help identify a potential problem in your trees.

Look for signs of infestation in Bay laurel trees which are generally infected before tanoaks. This is an advance warning sign. The disease causes the tip of the bay laurel leaf to die (see photo/should I send a photo?)

  • Susceptible trees develop a canker when infected. External signs of canker development may include the bleeding of a thick red-brown sticky sap.
  • Hypoxylon thouarsianum is a secondary pathogen that often attacks infected trees.
  • Oak Ambrosia beetle is a bark beetle that will often attack trees that are infected.
  • If you live in an area with tanoaks and bay trees you may see a high level of mortality in these trees as well as coast live oaks.
  • The pathogen can spread through water and is prolific in moist and humid conditions.

How to manage Sudden Oak Death

While there are no cures, there are preventive steps that can help protect trees including:

  • Selective removal of trees showing early signs of decline.
  • Selective removal of bay trees within 15 feet from the trunk of oaks.
  • Preventive application with Agri-fos or Reliant, and Pentra-Bark.
  • The disease can be carried on plants brought in from nurseries. Before bringing your new plants home, check them carefully and avoid plants with leaf spots or off-color foliage.

It’s hard to determine if sudden oak death is present trees in adjoining properties. And the pathogen infects new stands of trees every year. Work with your local certified arborists at Ned Patchett to keep a vigilant eye on changes in your region.

As an important component of your landscape, tree care should not be taken lightly. Our certified arborists at Ned Patchett Consulting are trained to care for trees of all shapes and sizes, and during all stages of life.

Are you looking for an innovative tree service and landscape design and maintenance company that will uniquely and passionately create and care for your trees and yard like they were their own?

Let the experienced professionals at Ned Patchett Consulting deliver for you. Connect with us at or 650-728-8308

#nedpatchettconsulting #suddenoakdeath #treecarespecialist #treestress #certifiedarborist #care oftrees #healthytrees #treewatering #native trees #earlyidentification #prevention

By |2020-01-20T21:34:07+00:00October 29th, 2018|Blog|