Much of England had been cleared as early as 1000 BCE, some two millennia beforehand. The Bronze Age saw intensive farming on a scale that we are only just beginning to appreciate. As Oliver Rackham puts it in The History of the Countryside:
It can no longer be maintained, as used to be supposed even 20 years ago, that Roman Britain was a frontier province, with boundless wild woods surrounding occasional precarious clearings on the best land. On the contrary, even in supposedly backward counties such as Essex, villa abutted on villa for mile after mile, and most of the gaps were filled by small towns and the lands of British farmsteads.
Rackham describes the immense clearance undertaken during the Bronze Age, boldly claiming that ‘to convert millions of acres of wildwood into farmland was unquestionably the greatest achievement of any of our ancestors’. He reminds us how difficult it was to clear the woodland, as most British species are difficult to kill: they will not burn and they grow again after felling. Moreover, in his dry phrase, ‘a log of more than 10 inches in diameter is almost fireproof and is a most uncooperative object’. The one exception was pine, which burns well and, perhaps as a consequence, disappeared almost completely from southern Britain, the presumption being that prehistoric man could easily burn the trees where they stood: the image of pine trees burning like beacons across the countryside is a strong one.
Or a contemporary of Stonehenge’s builders.
https://aeon.co/essays/who-chopped-down-britains-ancient-forests