Ban farming on that marginal land, and the rent on meadows will jump; where once the alternative to paying rent and farming on meadows was to farm on grassland rent-free, now there is no alternative. Farmers are much more eager to farm on meadows now that farming on the grassland is illegal, and the rent they're willing to pay is much higher too.
Another reason why property in London is expensive is because of the Green Belt.
The Green Belt keeps rents and house prices in London much higher than they would be, in exactly the same way as a ban on grassland farming keeps rents on meadow and scrub much higher than they would otherwise be.
This is not an argument against the Green Belt.
There are lots of benefits in having London's population capped at around six million people, instead of sixteen million or twenty-six million. But it is important that when we are weighing the pros and cons of legislation like the Green Belt, we understand that its effects are more than simply to preserve the environment.
The Green Belt has made property in London scarce relative to the people who want to use it, and of course, strength comes from scarcity.
