Re the tree planting thing the same idea is being mentioned on FB suggesting the numbers are so large that it would be impossible to physically have the time to plant so many trees. However if you look at the numbers as to what is happening now it seems that it is possible.

Labour want to see 300 million trees being planted over their first 5 years in office. This amounts to 60 million per year but it includes what is already being planted by the devolved administrations. Scotland alone planted 22 million trees last year! So that is one of the four UK nations whose population amounts to less than 9% of the total is already planting 36% of what the total annual target is under Labour for their first five years. So Labour's plans for their first administration aren't really that impossible as far as time goes. Surely if Scotland can plant about 4 trees per person every year - then the UK as a whole can plant what would be nearer 1 tree per person per year?? After that for the next five years it would need to be about 140 million per year to get to the 1 billion by 2030 which still only amounts to between 2 and 3 trees per person per year. Then it would reduce to a minimum 100 million per year between 2030 and 2040.

As to the space for the trees well I am sure once they got nearer the planned forestry extent then they could adjust. Though here in Scotland it is not all positive to be fair and where forestry is going to be and how it is done can be an issue as Iains suggests. Here in the Borders the Buccleuch Estate has been accused of pushing smallholders off the land to enable it to be sold for forestry.