See pictures below. I found five of them on a patch of oak seedlings in northern Turkey yesterday, they are about 2 centimeters in diameter and smell like grass.




Five months later: 4

I tried PlantNet and Google Lens before asking but nothing came up.

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    $\begingroup$ I've asked several botanists from North Caucasus, none of them know. Considering that it's green, it must be hemiparasite, like Viscum. $\endgroup$ Commented Jan 5, 2023 at 6:50
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    $\begingroup$ I wonder if these are galls formed by an insect. That may be who made the hole in the bottom in the third photo. $\endgroup$ Commented May 12, 2023 at 15:39
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    $\begingroup$ I second @Darlingtonia's comment. If you add your photo to iNaturalist, there is a user there, Megachiele (I don't know the name exactly), that is really good at galls. I've never seen a gall like that before. Really cool. $\endgroup$
    – John Polo
    Commented May 12, 2023 at 16:00
  • $\begingroup$ @JohnPolo Thank you both, I'll take a look. $\endgroup$ Commented May 12, 2023 at 16:06

1 Answer 1


I think these are galls produced by a wasp in the genus Andricus.

Here are some produced by A. polyceras: Three Andricus polyceras galls on a branch tip. ©iNaturalist user alexcm, 2021, CC-BY-NC

However, there are many species in this genus so more detail would be needed to narrow it down.

  • $\begingroup$ This looks very much like it, thanks. What more detail would you like me to provide? $\endgroup$ Commented Aug 30, 2023 at 15:35
  • $\begingroup$ I'm not familiar with this group, but a positive ID might require dissecting the galls, or capturing the wasps that emerge for inspection. The other most similar species I saw was A. quercustozae, but most of the photos showed much more bulbous galls. I didn't see any with the really narrow bases that your photos show. $\endgroup$ Commented Aug 30, 2023 at 15:48
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    $\begingroup$ The oldest relatives of these found in amber are from about 50 million years ago. They inject up to 70 active mutagens and viroids that hey use to control hosts. $\endgroup$ Commented Sep 1, 2023 at 2:44
  • $\begingroup$ Couldn't find any more galls to dissect. I'll go ahead and accept your answer, thanks again. $\endgroup$ Commented Nov 14, 2023 at 6:09

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