Why Purple?

The crude artificiality of heather moorland which only exists because man farms the land is illustrated very well by this poster from Eastern Moors - you know, that organisation that said it valued wild landscapes.

What is wrong with the natural colouring of the local hills? That would be various shades of green throughout Spring and Summer, changing to a great range of colours including gold, yellows and bronze during Autumn. Trees are of course the natural vegetation of these moors and it's only been supplanted by heather following intense human activity dating back many hundreds of years and encouraged and managed by the grouse shooting interests.