A few years ago when I was looking at houses in the country there was definitely some requirement for buying more than 30 or 35 hectares of farmland. And while you might be able to get permission to convert some areas into forests, it is explicitly stated in the planning laws that the character of the countryside is to be preserved. I can assure you that there are lots of things you can't do.

And before that, of course, there's the price. 50 acres way out in the sticks in America might be quite affordable. Arable land in Denmark, less so. There's no easy escape here like the post I reacted made it sound.