This is the initial sketch (below) made in charcoal on a heavy weight acrylic paper.
Here it is (below) after the first application of colour. I like it's freshness at this stage and I lose this a bit as I try to give the piece more depth. I really enjoy working with the wet paint and ink like this and look out for any happy accidents as the two meet.
This is the painting as I have left it (below). I have added more brown to convey the bog furrows underneath the heath and the grasses. I reduced the red a little but left a streak of it visible which I think gives it some direction and focus.