Pickman's model
Starry Wisdom
I think that's a great idea and planting a lot more trees has all sorts of advantages.
I am skeptical of the idea of it becoming 'a forest' in the sense it's supposed to make you think though. Where I grew up is just about in the zone given there, in north Lincolnshire, and it's all fields. I could see there being small areas where you could plant patches of trees but there's no scope for planting on a forest scale without getting rid of most of the agriculture (and therefore a huge chunk of the local economy) in the area. I imagine most of the area will have similar issues.
That said I think the idea really resonates anyway so hopefully they do well with it.
grimsby, cleethorpes, louth and immingham doubtless all swallowed by the forest