need help identifying some trees

Hello everyone!

I want to learn more about plants and I'm beginning with the trees in the forest near my home in Transylvania, Romania.

Thank you!

I'm not generally familiar with European trees, but 1 and 2 look like some variety of birch. I can't tell what 3 is, beech is possible but I wouldn't try to say so without more info. 4 suggests hickory; are there hickories in Europe? The growth pattern of 5 reminds me of maples, but I would need to see a closeup of twig and leaf before saying anything with confidence. 6 could be a black birch or a black cherry in the US, but I don't know what European trees would be similar to those.

Hopefully someone from Europe will chime in with more localized knowledge.

Thank you!

I don't think there are hickories in Europe. Could the one with the triangle be hornbeam? The bent, stripy one might as well be wild cherry, I thought of that too, looking forward to spring to figure that out

I think 1,2, and 3 could be cherry, maybe sweet cherry.  I’m not at all sure though.  Cherry trees have horizontal markings like that.

Hmm, there's a pretty small chance they're cherries, they're in the woods in the place where you don't usually find them. On second thought, 1 and 3 could be Alder.

This is my Montmorency cherry.