Hi Knut,
I am definitely no expert, but I've listened to Paul a lot and just made my own hugel. I know I've heard Paul talk about how we work with what we've got, so if you've got pine and food scraps I'd say go for it! You mentioned sheep grazing, perhaps you could dig some sod from someplace close to turn over onto your hugel? I used sod we'd dug to put in raspberries/blackberries elsewhere. Or how about sheep manure? Something to consider might be trying initially to grow some things that will help to mitigate the acidity of the soil (pine needles tend to make it more acid). All in all, of you can build it fairly easily it could be what you need to get some plantable soil going, probably not the first year, but worth a try! I hope you'll update us with what you end up doing.