This blue-green conversation
I look out from my living-room window into the dome of my street’s tree canopy, where broccoli tops of oak and cottonwood foliage sway atop the gimbaling buttresses of limbs. I’ve long savored the lofty discourse of these leaves—never laborious but conversational, nebulous, a shifting swell of tremor and blink as each leaf sways on its petiole.
Yesterday, first day of September, I spent transplanting divided perennials, a treasure-trove of Stella d’Oro daylily and bearded iris. They had been given by one of my wife’s colleagues, who delivered them to the office in grocery bags, each root crown or cluster bundled in damp newsprint. Unwrapping the bundles in my garden, I marveled at her craft: daylily crowns soilless and glistening, iris rhizomes cleft sharply, polished to a gleam. To bury these carefully-tended tubers seemed almost unfortunate, although it’s only in the dark of the earth that their uncanny shine can stem and foliate.
As I covered over the roots in the cool grit of garden loam, I was struck afresh by the bifurcated world of the vascular plants: the chill nourishing darkness of the soil below; the arid clarity of light and atmosphere above. How the plants live at the margin of this divided world; how they put this earthly border, this gradient of chemistry and energy, into conversation. The force that through the green fuse drives the flower is dialogic, double-dappled; turf and tree maintain this border even as they enliven it.
We’ve touched the substrate of several worlds, but Earth is the only place we’ve found soil—that remarkable mixture of geology, living organisms, and decaying organic matter skinning the planet’s surface. I first read this arresting observation in the writings of James Lovelock. For Lovelock, the real vitality of soil emerges at the edges it makes. “Living systems maintain themselves in a state of relatively low entropy at the expense of their nonliving environments, Lovelock and Dian Hitchock observed in 1966. “We may assume that this general property is common to all life in the solar system. On this assumption, evidence of a large chemical free energy gradient between surface matter and the atmosphere in contact with it is evidence of life.” Looking for ways to detect evidence of life from afar, Hitchcock and Lovelock realized that these edgy patterns of energy and chemistry, not microscopic evidences found in samples of gases and regolith laboriously collected by probes, could provide ample evidence of the presence or lack of life on Mars and other planets. This perspective opened the door to the Gaia theory, now closely associated with Lovelock and Lynne Margulies (though Lovelock himself has credited Ms. Hitchcock, who is now sadly unremembered, in glowing terms), which understands Earth as an interlaced vastness of living systems transgressing the classical boundaries of organism and environment, everything entangled in dialogic intimacy.
More recently, across a series of fascinating papers (the details of which I’m hardly equipped to understand), the Finnish biophysicist Arto Annila (sometimes working with his father Erkki, a forest scientist) argue that life arises naturally as a consequence of thermodynamics, as a phenomenon continuous with so-called nonliving chemical and physical phenomena—among the latest in a long fascination with self-sustaining complexity across a panoply of discourses in the sciences.
These discourses are just that—conversations across gradients of possibility, themselves consequences of, and continuous with, cosmic variety. On this Earth, there are many gradients—many substrates, many media, other than soil and atmosphere; life puts them all in conversation. The hero may have a thousand faces, but Gaia’s are numberless.
