Its chalk and natural grasslands have a large variety of rare herbs , including some which are nationally scarce , such as the wildflower greater yellow - rattle .
It is the most extensive area of semi-natural downland left in Greater London .
area 's chalk and natural grasslands have a large variety of rare herbs , including some which are nationally scarce , such as the wildflower greater yellow - rattle .
It is the most extensive area of semi-natural downland left in Greater London .