Picture this: You own a few hundred acres near a growing town that your family has been farming for generations. Turning a profit has gotten harder, and none of your children want to take it over. You don’t want to sell the land; you love the open space, the flora and fauna it hosts. But offers from developers who would turn it into subdivisions or strip malls seem increasingly tempting.

One day, a land broker mentions an idea. How about granting a long-term lease to a company that values your property for the same reasons you do: long walks through tall grass, the calls of migrating birds, the way it keeps the air and water clean.

It sounds like a scam. Or charity. In fact, it’s an approach backed by hardheaded investors who think nature has an intrinsic value that can provide them with a return down the road — and in the meantime, they would be happy to hold shares of the new company on their balance sheets.

Such a company doesn’t yet exist. But the idea has gained traction among environmentalists, money managers and philanthropists who believe that nature won’t be adequately protected unless it is assigned a value in the market — whether or not that asset generates dividends through a monetizable use.

The concept almost hit the big time when the Securities and Exchange Commission was considering a proposal from the New York Stock Exchange to list these “natural asset companies” for public trading. But after a wave of fierce opposition from right-wing groups and Republican politicians, and even conservationists wary of Wall Street, in mid-January the exchange pulled the plug.

That doesn’t mean natural asset companies are going away; their proponents are working on prototypes in the private markets to build out the model. And even if this concept doesn’t take off, it’s part of a larger movement motivated by the belief that if natural riches are to be preserved, they must have a price.