Rules of Thumb, 30x30, and the Laws of Nature

Spring Landscape (Rain), A. Krehbiel

My mother had a commonplace book in which she recorded, by hand, in beautiful cursive, proverbs, sayings, and quotes that struck her as interesting, thought provoking, or wise. I also love sayings, and quotes, and mantras, but mostly I’ve collected rules of thumb, those short pithy statements that condense ways of dealing with life on earth in the same way that proverbs give advice on how to behave in prudent, trouble-avoiding ways. 

Rules of thumb exist for every field of human endeavor. There are the general ones, such as the 80% rule, or Pareto Principle, that gets applied in sometimes surprising ways—"eighty percent of every thing is trash,” someone will say, or another will say that “80% of your output comes from 20% of your efforts,” for example. The 80/20 ratio is useful in all sorts of contexts. For example, in a perennial garden, the general rule (backed up by scientific evidence) is that about 75-80% of the plants should be native (local ecotype) for the garden to be ecologically functional as useful habitat for pollinators and birds. I’m sure anyone reading this will easily think up multiple rules that apply to whatever it is they spend time doing, whether it’s building a house, planning a wedding, or working in IT. Rules of thumb are usually based on long years of a culture’s or person’s experience and require knowledge and judgement to utilize properly, because we live in a world in which everything is situational and full of change. They are guidelines, not step-by-step instruction manuals. 

Underneath mutability, however, is granite: our human rules of thumb restate and are governed by the implacable laws of nature that underpin change in all its guises. In “A Natural History of the Future,” ecologist Robb Dunn describes the laws of nature such as gravity and entropy that govern the functioning of the universe. He then shows how the biological laws of nature that govern life on earth such as natural selection, the laws of diversity, of corridors and niches, and of habitats affect us now and what will happen in the future if we keep breaking them. He says that “the most useful laws of ecology and related fields…are, like the laws of physics, universal.” They are regular, not to be trifled with, and impossible to escape. In his view, this is the dilemma we are faced with today: modern, industrial society is predicated upon stepping aside from, evading, and attempting to overcome these laws in order to control nature. The fact that this won’t work has become abundantly evident. 

Because I spend so much of my time thinking about ecological relationships in the context of the practical work of native plant gardening and natural area restoration, most of my favorite rules of thumb address exactly the problem Dunn describes: the very human quandary of how to live in and with the natural world without wrecking it. For me, the best rules of thumb are the ones that informally restate the universal laws of nature and ecology in such a way that they incorporate into them morals and advice for specific human behavior. Thus, I follow as well as I can the ancient Native American—and, I’ve recently learned, old Celtic—great rule, or law, of reciprocity. This rule is powerful and profound enough to affect every aspect of all of our relationships, whether with other humans, other species, or the panoplies of habitats, plants, animals, soils and waters we call ecosystems. As a small example, when collecting seeds for propagation for restoration purposes I never take all of what a plant can offer. The rule says that because all life is interconnected and interdependent, whenever collecting seeds, or foraging for wild plants, or the like, one should only take a percentage. That way the plants can regenerate themselves and, in the case of berries, for example, birds and other animals will also have enough to eat. Down to the seventh generation and beyond. 

This rule could be expressed mathematically and scientifically. Ecologists discuss carrying capacities and create models that can calculate the amounts of seed needed for good plant reproduction, the amounts of berries needed for bird and mammal nourishment and seed dispersal, and describe the ways that the resulting functionality of the landscape will support a web of creatures, their habitat needs and their network of relationships. All very cumbersome to think about if you are, say, out on the sandy shores of Lake Michigan in Indiana or Michigan picking blueberries in the hot sun. It’s much easier to go by the rule: don’t strip the bushes; leave part of the harvest for other creatures and part for plant regeneration; help maintain harmony and don’t overstep the boundaries. 

Another favorite rule of thumb is related to the rule of reciprocity. It’s one I’ve written about before and have abided by so long I don’t even remember where I first encountered it—maybe when reading up on permaculture? When learning about regenerative gardening? Sustainable farming? Beats me. At any rate, here it is: if you own or control or manage land, as a farmer or a gardener, or homeowner, or large land owner such as a park district, or institution, thirty percent of that land should be left (or restored) as home and habitat for other species—preferably planted to at least 80% locally native plant species, since they actually create the habitat. If you do that, the whole place will be more biodiverse, and therefore more ecologically balanced, with real, tangible benefits in terms of water management, reduced pathogens, better air, and better land health overall. And for farmers, there will be increased yields. Even if you legally “own” a piece of land, with all of the ancient-Roman-derived property rights that entails, it is extremely bad karma—another way of saying against the laws of nature—to try to completely control it. 

The interesting thing about that 30% rule is that it has now morphed into a global initiative. If you somehow missed it this February, Part 2 of the Intergovernmental Panel on Climate Change, Sixth Assessment Report, reiterates that, “…maintaining the resilience of biodiversity and ecosystem services at a global scale depends on effective and equitable conservation of approximately 30% to 50% of Earth’s land, freshwater and ocean areas, including currently near-natural ecosystems.” This has become 30x30, the world-wide goal of conserving and restoring 30% of lands and waters by 2030, ultimately reaching the goal of reserving 50% of the planet for other species by 2050. Individual countries have already adopted the idea. In the US it is called the 30x30 America the Beautiful Initiative. At this fall’s United Nations Conference for Biodiversity, the parties will likely adopt this goal as part of the post-2020 Global Biodiversity Framework. 

If, by some miracle, humans do manage to set aside 30% of the planet for other species, wouldn’t that be enough? Why 50% by 2050? Fifty percent is the amount that E.O. Wilson and other biologists have calculated that would do the most for saving biodiversity overall. As he explained in his book “Half Earth,” he reckoned that something like 80% of species could be saved that way. Thus, 30x30 is an interim goal expressed as a rule of thumb derived from an equation describing the what I have known as the “island effect,” or as scientists have named it, the “species-area law,” which explains how the size of an island or other land area relates to the rate of biodiversity, speciation, and extinction. Roughly, the larger the island, or swath of natural habitat isolated by, say, industrial farm fields or housing developments, the higher the rate of biodiversity and speciation and the more species that can live, reproduce and thrive. The smaller the area, the fewer species that can carry on, leading to a higher rate of extinction. 

This law explains why preserving biodiversity means there should be corridors and large reserves wherever possible. 30x30 leading to 50x50 is a reflection of the biological laws of nature, as far as they can be described mathematically. It is rule of thumb taken to a planetary scale. It is a nature-based solution for mitigating climate change that would, according to Elizabeth Maruma Mrema, the executive secretary of the UN’s Convention on Biological Diversity, help end ecological destruction, help curb pollution, save biodiversity, help manage water cycles, and store carbon. 30x30 is also the latest in a long history of efforts since the beginning of the industrial revolution to incorporate room for other species in the physical realm, in our conception of justice, and in our sense of humans’ role vis a vis greater than human nature. 

30x30 is almost a romantic notion, though the wording is clumsy. The concept has a simple, fractal beauty, replicable at every scale: a balcony, a yard, a block, town, country, region, hemisphere, planet. Folded within it are indigenous teachings, Aldo Leopold’s land ethic, reconciliation ecology, the laws of reciprocity, and the rights of nature. Anyone can take part, wherever they are. 

There are critics. Predictably, the American right wing claims the idea interferes with property rights and will lead to a “federal land grab.” Critics on the left have pointed out that several large, monied foundations and “big green” organizations have gone all in on the 30x30 goal, donating money and expertise to the creation of a vast system of large, human-excluding nature reserves. There are fears that more indigenous people will be forced out of their homes and that the whole effort is colonialist and exploitive. These arguments don’t make sense to me. As far as I’ve been able to determine, there’s no land grabbing going on, and anyone who reads the IPCC report will notice that it specifically references equity and indigenous rights. 

In reality, owing to the constraints of the island effect, there is a necessity for large tracts of non-urban, non-agricultural wild land: many species of animal need room to roam, and to migrate, and many ecosystems need large expanses to thrive. Wilson, himself, was not talking about “fortress conservation,” in which people are not allowed into reserved areas and indigenous people are moved out in the interests of the animals and colonizing conservationists. He often articulated the idea that nature is everywhere, and that we can’t get away from it, no matter what. So yes, there should be vast, non-developed reserves—refuges, if you like (while we also desperately need to change how we approach land use where people live in cities, suburbs and on industrial farms). This doesn’t mean that humans can’t live within these areas, just that they would have to live differently, in ways that few westerners are willing to do. Eco-tourism might flourish. 

Be that as it may, conditions have changed. These days, indigenous people are widely recognized—especially by conservationists and ecologists, one might argue—as being among the best conservation land managers (to put it in Western terms) on the planet, people who can live on and steward large tracts of land better than nearly anyone else. Secretary Mrema says that indigenous groups are included in the ongoing negotiations and have been asked specifically for their input, especially since, for “80% of biodiversity in the world, the local communities are the custodians.” 

The true authors of current displacement efforts of indigenous people and a great deal of general environmental destruction are not conservationists, but rather are authoritarian governments, criminal gangs, and corporate interests, including fossil fuel companies: the scions and heirs of the old, deadly, ecosystem and culture-destroying colonial campaigns that first careened across the globe in the 15th century. To these entities I will also add any real estate developers who look at a piece of wild land with one objective: to build something on it, whether it be a resort, subdivision, or new road network. In light of who these groups are, how much power they wield, and how in so many cases the laws support them, getting to 30x30 will be a very stiff fight, indeed, with the odds being very similar to those involved in keeping global temperature rise to 1.5 degrees Celsius (2.7 Fahrenheit) or even 2 degrees Celsius (3.6 degrees Fahrenheit). That is, not very good at all. 

The answer, as so many of us have been repeating again and again and over again, year after year after year—and only confirmed and emphasized by this latest IPCC report—is that to avert the worst effects of climate change, tamp down on pollution, and avoid ecological destruction and the sixth extinction, everything—ethics, economics, business practices, basically the whole of modern industrial society, needs to change, to be conducted along different lines, and fast. 

30X30 puts all of this right on the line. 30x30 could work if, for example, we started de-privileging the rights of real-estate developers and privileging the rights of nature. If we began to operate our economy along steady state principles. If we changed our education practices, religious teachings, and developed a secular conservation ethic. Or conversely, if we used 30x30 to govern land-use decisions, all of these aspects of human society would start to change. It's easy to be cynical, yet 30x30 really is something new. It really is asking for all these changes in a new way, asking a whole planetary society to change, and local communities and individuals as well, asking across geographies, societies, cultures, and social categories. Yet, because it’s fractal, 30x30 would enable these changes to be carried out in every locale, in a myriad number of ways—by necessity, because it would work according to where exactly in the world conservation and restoration is being carried out. Is all that a tad scary? I find the alternative to be infinitely worse. 

Resources:

• “A Natural History of the Future: What the Laws of Biology Tell Us about the Destiny of the Human Species,” by Rob Dunn (Basic Books, November 2021) 
• Here I've discussed reciprocity more fully: Climate Change Doesn't Care about Anyone's Opinion: Notes on Reciprocity and Sacrifice
• “To Speak for the Trees: My Life’s Journey from Ancient Celtic Wisdom to a Healing Vision of the Forest,” by Diana Beresford-Kroeger (Timber Press, 2019) 
• “Half Earth: Our Planet’s Fight for Life,” by E. O. Wilson (W. W. Norton, 2016)
• Interview with UN Secretary Elizabeth Maruma Mrema by Daisy Dunne, Carbon Brief, April 6, 2022 
• IPCC Sixth Assessment Report Climate Change 2022: Impacts, Adaptation and Vulnerability
• An earlier discussion of "Half Earth," among other things: Ethics and Ecosystem Interactions: Why Reconciliation Ecology Matters