Close-up of part of an oak tree, Quercus sp., showing leaves, acorns and an unidentifed gall (the shapeless, shiny structure at upper left). A gall is

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Close-up of part of an oak tree, Quercus sp., showing leaves, acorns and an unidentifed gall (the shapeless, shiny structure at upper left). A gall is an abnormal outgrowth or swelling formed by a plant as a result of attack by parasites such as bacteria, fungi, nematodes, insects and mites.

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Size: 5079px × 4050px
Photo credit: © ADAM HART-DAVIS/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: botany, disease, diseases, gall, insect, leaf, nature, oak, parasites, pathogens, pathology, pest, pests, plant, quercus, sp., tree