Hmmm... I found this one tougher than expected. Did some tonal editing in the sky (and got rid of one "blob" (a sensor or lens mark just above the widest mountain) then went for a vintage warm glow and some HDR-style processing to add some menace
Small horizon adjustment, then a crop to centralise the "fan" of the field stubble, lose some of the empty sky and to give a panoramic feel, exaggerating the space. A little light grain and vignetting... Processing done in LR6 and Color Efex Pro... and then some more in LR6
EDIT: Re-posted my edit of the pic to include some spot removal of birds in the mountain areas