Sorting out history

When I was planning to visit Iasi in Romania, I looked at a map, saw that it was in the northern part of the country, and casually assumed that this meant that it was in Transylvania. Well, no. I’ve spent the last hour reading up in Wikipedia on the history of Iasi, Romania, Transylvania, and Moldavia, and I think I have it sorted at a superficial level. And calling someone from Iasi (Jassy) a “Transylvanian” would seem to be a bit like calling someone from Durham a Scot…

Moldavia, Wallachia and Transylvania at the end of the XVIth century
Moldavia, Wallachia and Transylvania at the end of the XVIth century

Another thing I’m sorting out is geography. I had looked at Google Maps images like this, and had assumed that Iasi was in a mountainous region – part of the Carpathians. Well, no. If I’d zoomed out a bit, like this, I’d have seen that it’s well to the east of the mountains, in what looks like a prime agricultural region.
Speaking of agriculture, can someone explain why all of the fields show this fine-grained irregular striping pattern. The link’s to a Google map zoom-in satellite view of fields just to the east of the Iasi airport, but I saw this pattern all over the country. (Here’s the same kind of thing just outside Bucharest.)