community watershed restoration since 1983

Sudden Oak Death Symptoms Caused by Other Pathogens: Some New Information

Combating the spread of sudden oak death is an important is very important to us at the MRC. Recently, Lisa Hintz has incorporated knowledge from discussions with Wallis Lee Robinson and Chris Lee into the following article about symptoms of sudden oak death. Here is an excerpt:

“Starting in early summer of 2021, UC Cooperative Extension and Cal Fire made a sampling effort in several north coast counties to associate observed symptoms with responsible pathogens. By November, 66 samples had been collected and apparently pathogenic organisms isolated from Del Norte, Siskiyou, Humboldt, and Mendocino Counties, and about half of them (30 samples) had been sequenced and identified. Of these 30 samples, 17 were affected by Tubakia californica, four by Diplodia corticola, one by Diplodia mutila, three by Biscogniauxia mediterranea, one by another Biscogniauxia species, and five by Diaporthe species. Other potential pathogens were occasionally isolated, such as Cladosporium sp., Paratubakia sp., and Apiognomonia errabunda (on leaves). On some batches of samples, secondary pathogens or saproptrophs were mostly isolated, suggesting that more primary pathogens may have initially been responsible but that isolations had not been conducted quickly enough to detect them.”

You can click here to download the full publication.