Think about it for a second – what would be wrong with a synthetic version of the wilderness, if you can still go hiking and fishing there? How about a virtual reality program that allows you to witness the fall colours of New England without going there?

It sounds facetious but this is a genuine question for some conservationists. In 1973 the theorist Martin Krieger wrote a Science paper asking exactly what would be wrong with plastic trees. His argument was that preservationism, which is concerned with maintaining intact ecosystems for their own sake, is more expensive than pragmatic conservationism, which aims to deliver the most benefit for a given cost.

Even pristine wildernesses are partly a construct of society, he argued. Niagara Falls is an icon of the natural world precisely because people want to see it with their own eyes. Diamonds are valuable not just because they are rare, but because we attach emotional and economic value to them. It’s the same with ecosystems such as state parks, Krieger’s argument goes.

Might we then be better off taking an economically pragmatic approach to natural wonders? After all Niagara is eroding away through natural proceses – are we just going to let that happen when there’s money to be made from people coming to see it? Can we predict when rockfalls might occur and turn them into a tourist spectacle?

In 1973 this was a pretty radical idea. But now it sounds less so. There is already a plastic-and-concrete forest in Florida called, inevitably, the Disney Wilderness Lodge. And some might argue that restored forests and wetlands are also, to a lesser extent, ‘artificial’.

Krieger concluded that “there is little wrong with [plastic trees]”. But was he right? Scott Cameron of Loyola Monument University doesn’t think so. Although Kriger’s argument sounds compelling in the terms in which he expressed it, even in today’s plastic, Disneyfied world it still sounds shocking. And there must be a reason for that.

Part of the pro-plastic argument is that, if we can recreate a synthetic version of the original that gives people the same experience, then we would be snobs to demand the real thing. But leaving aside the fact that most humans are snobs, Krieger didn’t realise the full price that we would pay for our pretend wildernesses. And why would you pay top whack for a fake diamond?

The hidden costs of fake wildernesses are not direct monetary ones. Instead, we lose ecosystem value further down the line. The idea of ‘staying home to go outside’, rather like watching a wildlife documentary on television, inevitably creates a two-tier society between those who get to experience the real thing in order to set about recreating it, and those who either witness the make-believe version or don’t get to experience anything at all. Cameron argues that it’s a slippery slope in which the poor never become engaged with the natural world at all, whereas the rich lose sight of the importance of natural wildernesses as they begin to believe the hype, the marketing message that the Disney version is better.

It also strikes me that while Krieger’s argument might apply to wildernesses, from which the main ecosystem services to humans are recreational ones, it can’t be extended to other sorts of ecosystems that deliver crucial benefits of other kinds. To put it more succinctly, you can’t grow a plastic crop, eat a virtual steak, or drink a synthetic glass of water.