Diseased oak tree. View looking up at an oak tree with dead leaves. This is an early sign that the tree is infected with Phytophthora ramorum oomycete

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Diseased oak tree. View looking up at an oak tree with dead leaves. This is an early sign that the tree is infected with Phytophthora ramorum oomycetes. Oomycetes are a group of filamentous, unicellular micro-organisms that physically resemble fungi. Phytophthora ramorum causes the disease known as sudden oak death, which has had devastating effects on the oak populations in California and Oregon in the USA.

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Size: 3418px × 5138px
Photo credit: © PEGGY GREB/US DEPARTMENT OF AGRICULTURE/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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