Was sind das für Beeren? Sind sie essbar? Vielleicht wurden sie mit meinen Heidelbeeren vermischt

They are [crowberries](https://en.m.wikipedia.org/wiki/Empetrum_nigrum), completely fine to eat.

It’s variksenmarja (Empetrum nigrum). It is edible but not as tasty as bilberries. You can use it for pastries, soups, smoothies, porridge etc. Read more i[here](https://www.martat.fi/ruoka/ruoanvalmistus/ruoka-aineet/marjat/variksenmarja/) in Finnish.

I actually like the juice that comes out of these. I do spit out the rest of them, though.