Snowdonian farm becomes National treasure

The glaciated landscape which inspired a nation of poets and song, and where Sir Edmund Hillary trained to climb Everest, was suffering from intensive farming when the National Trust bought it 10 years ago Photograph: Joe Cornish/PR

A Welsh Black cow and calf among the cottongrass. Re-introducing cattle to the farm not only produces organic beef but also helps the regeneration of the land because their hooves break up the ground, enabling new plants to grow Photograph: Joe Cornish/PR

Repairing the traditional dry stone walls which criss-cross the Snowdonia National Park Photograph: Paul Harris/PR

Farm manager Arwyn Owen with Welsh Mountain sheep. The sheep flock at Hafod y Lan was cut down to 1,500 plus 500 lambs Photograph: Joe Cornish/PR

Overhead view of the Welsh Mountain sheep in the sorting pen before shearing. The flock was reduced from 5,000 sheep because they were relentlessly eating the sweetest grasses, bilberry and heather, and chomping down any saplings that might have grown into woodland Photograph: Joe Cornish/PR

Hafod y Lan fleeces are used, among other things, to insulate boxes of lamb sold directly from the farm Photograph: Joe Cornish/PR

Hafod y Llan farm Snowdonia, Wales Photograph: Joe Cornish/PR

Farm machinery on Hafod y Llan farm, Snowdonia Photograph: Paul Harris/PR

Ten years on, the uplands of the farm show more diversity with heather, bilberry and Sundew and mosses. "It’s looking more diverse: more of a pattern of colours and textures,” says the National Trust's local manager Photograph: Joe Cornish/PR