Black Knot (Apiosporina morbosa), a plant pathogen, growing on a rotting tree branch.

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Size: 5000px × 3333px
Location: West Harrison, NY, United States
Photo credit: © Clarence Holmes Wildlife / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: america, american, apiosporina, ascomycota, black, dothideomycetes, fungi, fungus, knot, morbosa, nature, north, sac, states, united, usa, venturiaceae, venturiales, wildlife