plagiotrochus quercusilicis galls on quercus faginea gills with a very peculiar appearance like green grapes produced by an insect

acorn ancient autumn botanic botanical botany branch closeup damage damaged dangerous detail disease dried dry ecology engraved fall floral forest gall green grown hymenoptera infected infection infectious insect isolated leaf nature oak old parasite parasitic pest picture plant print quercus selective sharpened sunlight tree vignetting wasp wood yellow