Trees need a lot of water... so there's a reason there are vast unforested plains in the world. Humanity's deforestation creates way, way more spaces without trees, but I'm not sure if that photo is a forest friendly climate cut down to make room for a wind farm. It might be there's just not enough water for trees, and the sheep are what need to be removed since they're not adapted to living on scrubland without abundant water and shade.