Some sentimental souls like to imagine that the countryside is wild. Yet every acre of bleak moorland, every deep, dark forested glade and every blade of grass on every chalky down is there, in large part, through the management of man.
It is not just habitat that has been shaped through generations of human endeavour, from the ancient peoples who cut down the trees to turn Dartmoor into what we see today, to the 18th century landowners who planted the hedges as part of the enclosures.
Animals and plants have also been brought to these shores, making our flora and fauna an eclectic mix of natural and introduced species.
Some of those that were introduced are much loved and well-looked after. But many cause us problems and some even threaten the indigenous species that have long since called Britain home.
Public enemy number one, for naturalists working to bring the red squirrel back to the level he once enjoyed in his native Britain, is his close cousin, the grey.
Grey squirrels were introduced to the UK in 1876 when a Victorian banker, Thomas Brocklehurst, released a pair into the wild on his estate at Henbury Park in Cheshire. Like many immigrants, the greys took to their new home with gusto and proved incredibly successful. There are now an estimated five million in the woodlands of the UK.
There is a problem, however. The greys are carriers of a disease that does not harm them but causes ulceration of the eyes and nose in red squirrels, killing them in less than seven days. As a result, it is feared the red squirrel, already pushed back into a very few areas of Britain, could be extinct within 20 years.
The only way to save them, according to many naturalists, is to completely eradicate the greys.
It is an uncomfortable policy, even for those fully accepting of the need to control animals in the countryside as part of the management of wildlife.
There is similar controversy, for example, of the ruddy duck, another immigrant from the United States that poses a threat to the "purity" of a species of duck resident in Spain. It is subject to an officially sanctioned total annihilation policy in the UK.
Defra has put a bounty on every ruddy duck's head and, it is reported, duck hunters are close to finishing them off.
Grey squirrels can legally be shot as pests and many foresters, woodland bird lovers and others do carryout extensive culls, "poking" dreys to destroy the squirrels' homes and shooting or poisoning the mammals. The effect in most areas is to keep numbers down rather than totally remove the population.
But in a number of areas, including a site in West Cornwall, efforts are being made to completely wipe-out grey squirrels before releasing their red cousins back into the wild. Natasha Collings, project co-ordinator for the Cornwall Red Squirrel Project, told The Times recently: "If you want reds you have to kill greys. It's a fact."
She is working on a Prince Charles-backed initiative that is working towards eradicating grey squirrels from two areas of Cornwall – one on the Lizard, the other in West Penwith – before captive-bred reds are released.
If successful, the plan is to push out the greys from areas further east, into Devon, and allow the red squirrel to re-colonise areas from which it has been largely excluded for years.
The project, like that in other parts of the UK, is not universally supported, however. BBC wildlife presenter Chris Packham has slammed those behind attempts to bring back red squirrels as "blinded by sentimental racism."
The vegan-supporting animal rights group, Animal Aid, called for a boycott of Duchy Original products to send a message to Prince Charles on the issue. The alternative to the destruction of the grey squirrel, however, is likely to be the extinction of the reds. Thomas Brocklehurst has a great deal to answer for.