Just saw the movie War Horse, a very pretty film. But Steven Spielberg is no farm boy. The first third of the movie is pre-war, when the thoroughbred Joey, the War Horse to-be, is trained both as a riding horse and a plow horse. In order to pay the rent, the father has promised the landlord to plant a field to turnips. Supposedly the field is both virgin and stony, impossible to plow. Sure enough, it's on the side of a hill and the ground is strewn with stones (though it's not clear whether they're weathered from the bed rock, which in Devon would be sedimentary, or glacial, rounded by water).
For dramatic purposes I can understand the decision to plow uphill, it makes the task for Joey more imposing, though it makes no sense from an erosion standpoint. When you see the first furrow plowed, and all subsequent furrows, somehow there's no stones in the soil, just good black soil.
Once the field is plowed, the father, limping from a war wound, starts sowing seed by hand. broadcasting across the furrows (no harrowing recorded). I could almost swear it was oats in the container, but I can't swear to it. Now, through the miracle of Hollywood, all that broadcast seed turned several weeks later into neat rows! of turnips. Unfortunately there's a big storm which somehow seems to uproot all the turnips, ruining the crop and creating another crisis for the family to face. I suppose the torrents could have eroded the dirt between the rows, but that didn't seem to be what happened.
I could go on to criticize the placement of the machine guns, but I won't.
It's a must see, if only for Emily Watson, who's always great.