All The Trees We Need?
We seem to lack the imagination (or courage) to grasp the concept of finiteness
Two recent newspaper articles drew my attention this weekend because they exemplify an attitude that I find impossible to comprehend: infinite supply. It’s easy to forget in the moment that some commodity is limited when the amount directly in front of you feels vast compared to your immediate needs. Take the mundane example of ketchup at a picnic. If the ketchup bottle is full, you don’t give a moment’s thought to how much you squeeze onto your burger, but if the bottle is nearly empty you will give some consideration to how many other people might also want ketchup. Is there another bottle in the cooler over there? Has everyone else already eaten? The full bottle represents something that engineers refer to as an infinite acting reservoir. Squeeze as hard as you want to on that full bottle: the maximum rate of ketchup flow is controlled not by your grip strength, but rather by the size of the hole in the spout. That sensation of effortless and boundless flow helps to sustain the illusion of infinity. A nearly empty bottle, on the other hand, produces a disconcerting “glurg—pfftht” sound which lets you know instantly that the supply of ketchup is dangerously low.
When President Trump declares that “we have all the trees we need,” I want badly to give him a squeeze bottle of ketchup, painted green and labeled Liquid Trees. Perhaps with practice he would learn to intuit that too much logging (squeezing) is indeed possible. To be fair, perhaps he had some hypothetical level of sustainable logging in mind when he asked the Agriculture Department to expand wood production from national forests by 25% as a way to undercut (these puns write themselves, I swear) imports of Canadian forest products. But I doubt it. Mainstream economists and businesspeople treat every commodity on earth as an infinite acting reservoir. Our civilization is structured to operate on the premise that the human economy is small compared to the size of the surrounding environment. That premise was once reasonably valid, but it has been a terrible assumption for generations, beginning with the Industrial Revolution and especially since 1945. Let’s not forget that trees are a major source of replenishment for the oxygen we breathe. A recent BBC Science Focus article estimated that seven or eight trees per person are needed to replace the oxygen we consume annually.
That’s a good segue into the next of this weekend’s news items that captured my attention. Two economists from the University of Texas at Austin have published a new book called The Depopulation Bomb in which they claim that more people are better in an apparently unqualified sense. As reported by the Wall Street Journal:
“…Spears and Geruso show how humans, through ingenuity and behavioral change, have reduced pollution and expanded available resources as their numbers grew. For example, in 2013, China’s smog was among the world’s worst. Over the next decade its population grew by 50 million, but particulate air pollution fell by half. As India’s population has grown, so has the average height of its children thanks to better nutrition and sanitation. Britain’s per capita carbon emissions have fallen by half since the 1950s. With industrialization now in the past for most countries, “the lifetime climate footprint of an extra baby has been declining,” the authors note.”
OK, but are those extra babies breathing less oxygen over their lifetimes than did their parents (or great-great-great-great grandparents)? Quite the contrary, as human life expectancy has increased dramatically almost everywhere over the past several generations. The point being that raw materials and basic life support resources are limited in supply by the amount of each originally present on Earth when it formed. We can and do apply gargantuan amounts of energy to chemically and physically transform materials from their natural states into forms more useful to our species. But we can’t do so without limit. The notion that fundamental limitations to all industrial processes exist is obvious to people who have studied thermodynamics. Most economists either have not, or else refuse to accept its conclusions. Everything we use is limited in supply, from water and nitrogen to iron and lithium. Mining geologically concentrated deposits of minerals (and that includes aquifers we drain faster than nature can recharge) is a one-time withdrawal from our resource account.
Perhaps the language of finance would help make this clearer to more people. One of my fellow Texans won $1 million this past April from a scratch-off lottery ticket. The winner wished to remain anonymous, but for purposes of illustration let’s call her Lupe. Lupe can spend her $1 million (we’ll forget about taxes here—just for fun) all at once in an epic splurge at the Galleria Dallas. But Lupe is smarter than that. She wants to use her winnings to fund an annuity so she can have money to spend for life. She deposits her money in a certificate of deposit (CD) at the Big Bank of Dallas, where it earns 5% interest per year. Now Lupe can spend $50,000 per year—every year—and have the same amount of money left over each time through the magic* of capital appreciation. Of course, Lupe, being a smart cookie, also realizes that inflation is out to get her, so she only spends $30,000 per year and allows the principal to rise gradually as an inflation hedge. If Lupe were ever to dip into that principal, for example to pay off her wayward brother Armando’s gambling debts, then her annual income from capital would be permanently diminished unless or until she stopped spending entirely long enough for the principal to grow back to its original value.
Farmers call spending in excess of your rate of replenishment eating one’s seed corn. It’s just as important a concept in our national forests as it is in the cornfields. With some resources, like oil and gas, the replenishment rate is so imperceptibly slow that there is really no point in even considering it: once we use a barrel of oil it is gone. The same can be said with even greater force for deposits of metals, so we need to be very intentional about where and for what purposes we use those deposits. In response to economists who claim that the human population can grow uninhibited with no adverse consequences, I would at least ask that we preserve a few forests. For each one billion people alive we need to preserve approximately eight billion trees to prevent suffocation. Right now, there are still around three trillion trees standing worldwide, so no worries yet. But since that’s roughly half the number that existed before human civilization arose, we might want to go easy on the sawing. And, there are also a lot of other oxygen breathing animals counting on us to do the right thing.
* I say magic of capital appreciation because, in truth, core financial assumptions of infinite growth are equally illogical. The only way that capital can grow “forever” is to continue consuming material resources to manufacture products that are in turn sold to earn a profit. At some point, the music will stop, and someone will be left standing.