Photosynthesis is my keyword for this era that we keep calling the Anthropocene. Photosynthesis circumscribes a complex suite of electrochemical processes that spark energy gradients across densely folded membranes inside the symbiotic chloroplasts of green beings (Margulis and Sagan 2000). Textbook diagrams familiar from high-school biology class are simplistic renderings of that utterly magical, totally cosmic alchemical process that tethers earthly plant life in reverent, rhythmic attention to the earth’s solar source. The photosynthetic ones—those green beings we have come to know as cyanobacteria, algae, and plants—are sun worshippers and worldly conjurers. Lapping up sunlight, inhaling carbon dioxide, drinking in water, and releasing oxygen, they literally make the world. Pulling matter out of thin air, they teach us the most nuanced lessons about mattering and what really matters: their beings and doings have enormous planetary consequences.

To name photosynthesis as a keyword for these dire times serves as a crucial reminder that we are not alone. There are other epic and epochal forces in our midst. Photosynthetic organisms form a biogeochemical force of a magnitude we have not yet properly grasped. Over two billion years ago, photosynthetic microbes spurred the event known today as the oxygen catastrophe, or the great oxidation. These creatures dramatically altered the composition of the atmosphere, choking out the ancient anaerobic ones with poisonous oxygen vapors (Margulis 1998). Indeed, we now live in the wake of what should be called the Phytocene. These green beings have made this planet livable and breathable for animals like us. We thrive on plants’ wily aptitude for chemical synthesis. All cultures and political economies, local and global, turn around plants’ metabolic rhythms. Plants make the energy-dense sugars that fuel and nourish us, the potent substances that heal, dope, and adorn us, and the resilient fibers that clothe and shelter us. What are fossil fuels and plastics but the petrified bodies of once-living photosynthetic creatures? We have thrived and we will die, burning their energetic accretions. And so it is not an overstatement to say that we are only because they are. The thickness of this relation teaches us the full meaning of the word interimplication.

Plants are a force and a power to be reckoned with. But we are ravaging the forests to make way for industrial crops and plantations (Gordillo 2014; Tsing 2004), paving over agricultural lands (Bellacasa 2015), filling in swamps, wetlands, and bogs (McLean 2011), and acidifying the oceans (Helmreich 2009). Plants have a remarkable capacity for widespread movement, but they can’t run fast enough to keep up with climate change. Worse is that in the fetishization of global carbon budgets as the ultimate metrics of planetary health and viable futures, plants and trees are, in some accounts, being rendered climate criminals. The argument goes like this: as climactic shifts make forests more vulnerable to fire and insect infestations, forests will cease to be sinks for atmospheric carbon and become unstoppable sources. But the grounds for such claims are shaky: it is not clear how forests sequester and release carbon or how best to monitor and quantify these processes (Buchholz et al. 2013), let alone how to analyze the other complex and concatenated cycles involved in forest metabolism. As a result, impoverished data and models are being fed into a calculus that justifies—in the name of climate action—what is, in effect, a vast and expanding resource grab. In one of the most egregious examples of the misuse of climate data, the former Conservative government reworked Canada’s forest policy to argue that old-growth forests must be logged now to make way for young, managed forests, which, according to their models, absorb more carbon from the atmosphere (Myers 2015c). One atmospheric scientist at Yale University is even attempting to argue that we must stop planting trees if we want to mitigate climate change. Plants, she claims, are prime sources of those noxious, volatile compounds contributing to greenhouse gases. Deforestation will—she promises—help to cool the planet.

Models are, of course, models of models of models, all the way down (Edwards 2010). Even still, NASA’s time-based simulation of the global carbon cycle, visualized over the duration of one year, offers one way that we might begin to render the force and power of plants on this planet. In this rendering, carbon dioxide, coded red for emergency, can be seen to accumulate with alarming intensity. Note the distinct fluxes and flows taking shape in the Northern and Southern Hemispheres. Note the uneven distribution of massive carbon plumes generated in zones of heavy industrialization. Pay close attention to what happens month by month as the seasons change and Northern forests begin to photosynthesize in the summer. We need to learn to read this simulation, not for data to feed an economizing logic that sees plants and trees performing ecosystem services, but as a document to remind us that we are not alone.

This is clearly no time to be making enemies. It is time for a radical solidarity project that insists that we are of the plants. I propose that we check ourselves out of this tragic anthropocentric fantasy (see Haraway and Kenney 2015), so that we can root ourselves firmly in an epoch that I want to call the Planthropocene. The Planthropocene names an aspirational era, one that must be marked by a profound commitment to collaboration. It is a call to change the terms of encounter, to make allies with these green beings. To do this we must relinquish control and abandon the notion that we have domain over these living beings (see Myers 2015b). We must get to know plants intimately and on their terms. And so we need a planthropology (Myers 2015a) to document the affective ecologies taking shape between plants and people, to learn to listen to their demands for unpaved land and for a time outside of the rhythms of capitalist extraction. We need to tap into their desire for forms of life that are not for us. To do this, we must learn to vegetalize our all-too-human sensorium (Myers 2014) and involve ourselves with plants (Hustak and Myers 2012) in an effort to reconstitute a planet fit for "collaborative survival" (Tsing 2015). If not, their undoing will truly be our undoing.