# Lunar Refractions: Leaves That are Green

There is nothing new under the sun.  —Ecclesiastes

Deus creavit, Linnaeus disposuit. (God created, Linnaeus organized.)  —Linnaeus

It is ninety-nine degrees in New York today—welcome back to yet another summer. This means, dear reader, that unless you are reading this in the southern hemisphere’s fine winter, or from the lofty alpine altitude of a mountaintop, or from some summery yet climatically kinder seaside, your sweat glands are working as hard as mine. The ninety-nine is, of course, Fahrenheit; although the city’s balmy streets feel as though they’re boiling, we have about 113 degrees to go for that to actually happen. In any case, this tropical weather has me operating on tropical time—that is, a bit more s l  o   w    l     y. Yet time and the measure of its passage, much like the Fahrenheit scale, often seem to follow some arbitrary measure—sure, sexagesimal for minutes and anything larger, decimal for anything under a second, now that’s consistent—so we go on as we always do, perhaps in slightly skimpier clothing.

It is in weather like this that I become aware of Mother Nature asserting herself. We can hide in the cool breeze of air conditioners, but they only spew more hot air onto the streets. Also, it’s never very cool to see the electric bill jump a decimal point or so in the sunny season, unless our excesses lead to a blackout—an unbelievably cool reminder of what luxury we normally live in, and how divorced we are from the world around us. But getting back to heat and the arbitrary nature of its measurement, there is a more ordered system (found, naturally, outside U.S. borders): ninety-nine Fahrenheit is equivalent to thirty-seven centigrade or Celsius. These two systems are generally considered interchangeable, but in their difference lies my interest: both have a tidy base unit of ten, but whereas the former name hinges upon its two fixed points (0 and 100, hence centigrade), the latter is named for an individual. Eighteenth-century Swedish scientist Anders Celsius left his name to the system he’d created for use in his own laboratory and observations, with boiling at 0 and freezing at 100. Yet another eighteenth-century Swedish scientist, Celsius’s colleague Carl Linnaeus, switched that system on its head, creating the system we now use. It may be sheer coincidence that one man helped give us both the world’s most widely used thermometer and the highly elegant system of binomial nomenclature; coincidence or not, it’s certainly convenient for me, because the heat that so upsets my own physiology proves a boon to that of my plants, bringing us back to these cyclical seasons, degrees of coolness and warmth, states of decay and growth.

Last summer I was surprised to learn that Linnaeus himself had laid the groundwork for the botanic gardens in Palermo, which were quite dusty on the dry July day I visited. Today, I just returned from my third visit to a much greener earthly paradise, a rural garden created by some delightfully eccentric family members of mine. Begun just over a year ago, this work-in-progress is now well underway, and the tree-room they’ve built is not only visually striking, but is also much cooler than any of my rooms at the moment. Right before leaving I made sure to water my own little urban garden, spread across several sills in my apartment, and crossed my fingers that it would survive my short absence (so as not to disturb friends or neighbors with the hassles of tending to my precious potted pets, a ritual that includes the arts of song and conversation). As I walked in this morning, everyone seemed to have flourished despite, or perhaps because of the neglect—parsley, sage, rosemary, two types of thyme, a mixture of various mints, an azalea, and a veteran jasmine who’s seen tough times yet still sends out flowering shoots of delightfully white, perfumed blossoms. My humble apartment garden is almost the antithesis of the one I enjoyed this weekend, and the backyard gardens my grandparents and parents cultivated falls somewhere in between, though decidedly on the more utilitarian end of the spectrum. Seeing both the growth spurt in my city garden and the remarkable transformations in the country garden since my last visit, the hot spell became instantly more tolerable. Picking up the sweet jasmine blossoms that had cascaded to the floor while I was out, and seeing how their snowy white had turned to a less lively yet more stable brown, I realized that color was one of the many characteristic browns I’d seen between the pages of botanist Ulisse Aldovrandi’s herbarium a couple of years ago when doing some research at the University of Bologna. Perhaps it was the humid heat having its way with me, but I began to think—what if one were to gather all the world’s herbaria; could its countless browns be categorized by area or period, or would there be a family of browns common to them all? Would the resplendent greens of a boxwood in Michigan collected in 2008 dry to the same browns of a boxwood in Milan collected at the height of its verdant life in 1608? Scientifically speaking, these are frivolous questions, as I’m sure that each naturalist collecting plants along her travels, looking back over the accumulations after time has sapped each specimen’s color, naturally sees them in their original splendor. Aesthetically speaking, however, the answers could be quite curious. And we’re back to Linnaeus, whose herbarium, much more recent than Aldovrandi’s, gives us a glimpse into the mind and eye of one of botany’s greats.

I’ll save my musings on the history of ecology for a later column, and will briefly focus instead on these potentially tenuous aesthetic connections. In their early twenties, Simon and Garfunkel were already wise enough to note that all “leaves that are green turn to brown.” Indeed. Earlier this spring, in mid-April and just before the major art auctions, I caught a striking, deep brown image of a single leaf in a New York Times article; it was a “photogenic drawing,” a proto-photogram about to go to auction. The image was believed to have been produced around 1839 by William Henry Fox Talbot, and had been brought to an expert in the history of photography for confirmation and a potential poetic blurb in the auction catalogue. The expert’s reply that it was certainly no Talbot, but may date back to the 1790s, making it one of the oldest photographic images in existence, caused quite a stir and may eventually lead to research that remaps the history of photography. All that, from someone’s simple impulse to make a sunprint with what was probably the closest and most obvious object close at hand: a leaf.
So the outline of a leaf that lived over two centuries ago was captured in a brownish light-sensitive emulsion quite close to the tone of its predecessors, actual leaves pressed between the paper leaves of volumes upon volumes of botanical matter now housed in archives throughout the new- and old world. Both have survived the heat of hundreds of summers, and float into our air-conditioned, digital-driven, image-laden times like deciduous gems falling to a cool forest floor to nurture the next wave of life.