Bur oak blight, caused by a new species of Tubakia


Blighted bur oak trees Pycnothyria

A poster of the disease cycle is available.

This is a link to a 2010 video (actually a powerpoint presentation) on bur oak blight, caused by an undescribed Tubakia - "What about BOB?"

An article (Feb. 2011) on bur oak blight was published in the ISU Extension 2011 Horticulture & Home Pest Newsletter, and a recent update (Sep. 2012) includes some discussion of potential fungicide control for high-value trees 2012 Horticulture & Home Pest Newsletter.

There's also a short video clip from a 2008 TV news report on the disease.

The US Forest Service has issued a 2-page pest alert on bur oak blight.

The formal description of bur oak blight and Tubakia iowensis was recently published in Mycologia and is available as a pdf. (Harrington, T.C., D. McNew and Hye Young Yun. 2012. Bur oak blight, a new disease on Quercus macrocarpa caused by Tubakia iowensis sp. nov. Mycologia 104: 79-92).

Doug McNew has been very busy finding new counties with confirmed bur oak blight. The current (as of March 2014) ISU distribution map of confirmed Tubakia iowensis is shown below as magenta counties superimposed on the gray distribution of Quercus macrocarpa. Yellow counties are where Doug looked at bur oak but was not able to find BOB (if you see BOB in those counties, be sure to let us know). We think this BOB distribution roughly coincides with the distribution of Q. macrocarpa var. oliviformis. Thanks to the numerous cooperators in Iowa and neighboring states for sending samples!


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