Forum Flora Germanica

http://agrozoo.net/jsp/Galery_one_image ... df6d195ebf

Resembles according to comparison to google images but I think not it.

Botanical garden Ljubljana, must be from some tree, could not figure which.

AFAIK Carya ovata not there.

assuming middle one is C.cordiformis (+ some other images on net.)
https://www.baumkunde.de/Carya_cordiformis/Bild2/

Carya fruits are quite similar, and determination with it is fairly problematic. The only one you probably can exclude here is C. laciniosa.
Determination goes usually through buds, twigs and leaves (and even that is problematic in this difficult genus).

Regards, Michael