Late-August heat on an early June day had already seemed to push spring’s raw greenery toward the dry gold of summer’s end. Or so I sensed after several hours at Brice Marden’s studio in Tivoli, New York, newly attuned to verdure during my visit—the varieties of hue and texture in a grassy slope studded with anthills, expanses of puckered moss, a clutch of young fruit trees, a looming fir, even the painted green of exterior window sills and of a cross fading from the north side of the artist’s house at Rose Hill, which was operated as a farm by the Catholic Worker Movement in the 1960s and ’70s.

The new paintings underway in Marden’s studio are green, and all the same green. This is factually accurate, yet the opposite is true as well: the new paintings are not green and they are not all the same. Some are dun, some are almost pitch, some seem cast with that dry late-August gold. The canvases are identical in size and format, and united by conceptual and procedural program. They happen, however, in person, and with astonishing variability. Each is a monochrome painted exclusively in a hue called terre verte, and each exclusively in the terre verte of a different brand.

Marden has used Williamsburg paints for years, but here now as well are Blockx, Holbein (Verona), Holbein (Terre Verte), Sennelier, Winsor & Newton, Old Holland, Rublev (Verona), Rublev (Antica), and Vasari (Ancienne). One side of the studio’s front room is lined with shallow baking trays, which house the distinct terre verte paints thinned with fragrant terpineol. These pans are protected by pieces of cardboard that bear the relevant brand name in charcoal along with a brush, leaking color where it rests. Behind them, small cans and tubes wait in orderly piles, every one of which for me registers as a question mark: how luscious or uneasy will this one feel on the brush? How rich with pigment, how matte of finish?

On the day of my visit, this room’s generous bank of windowed doors is open to the air, and the equally generous array of ceiling lights is switched off. Marden does his painting on the north wall of this space, where one canvas currently leans, dark and gleaming from a fresh layer of color the day before. A hand-drawn chart on a long side table helps him track the number of layers already laid down, aiming for parity across the canvases. All of them received a full single coating to start with, while their remaining layers are applied one by one within a 6-by-6-foot square. The freshest coat, still inky today, will take at least a week to dry, and so to reveal itself. It will then be covered over by another. Or, more to the point, it will be augmented by another, which it will likewise enrich.

In medieval and Renaissance painting, terre verte was commonly used as underpainting—for flesh tones, in fact, “green earth” supporting bodies in more ways than one. The intensive layering of thin veils of color, to sensuous and unexpected effect, is not new in Marden’s practice. Indeed, the layering of colors in his work is more often revelatory than strictly obscuring. Only since turning to terre verte for this new body of work, however, has he layered paint of a single color, at once reducing and heightening his terms. This color gained historical primacy as underpainting because of its translucency, and Marden works each layer of it less than usual—letting the color’s available density accumulate instead of wiping or scraping it away.

We might thus count these terre verte paintings as the artist’s most definitively “monochrome” works, yet Marden seems to hesitate over the accuracy of the word even here. When we spoke—two of the paintings finished, the other eight nearly so—he expressed mild surprise that the surfaces did not all simply read as more or less black. Marden first emerged, in the 1960s, as a painter of monochromes, and his panels of distinctive color looked singular precisely because they contained multitudes, so to speak. In notes for his five Grove Group paintings of the 1970s, among his last monochromes before he turned to an ultimately calligraphic lineation, Marden underscored plurality: the sky in Hydra, Greece, was “blue, gray, yellow, sulphur, turquoise, yellow, blue”; an olive grove was “evasive silver gray green, blue gray green light, black gray browns.” (It is worth noting here that terre verte was among the colors used in the Grove Group paintings.)

Meanwhile, the current terre verte paintings suggest that even a single color isn’t a single color. A decade ago, Marden marked his return to monochrome after nearly thirty years with Ru Ware Project, a nine-panel painting in a range of pale blues across which he tried to recreate from memory the unique coloration of the ancient Chinese Ru-ware pottery he’d seen in Taipei in 2007. If color in Marden’s work is typically either memorial or associative, color in these new paintings appears to function otherwise. It is the earthiness of terre verte’s “terre” that he is after, to be sure, but this isn’t the memory of something we’ve seen before. Rather, this is seeing as if for the first time; put another way, this is painting in order to see, study, glean—layer by layer, canvas by canvas.

That said, these paintings do not need to operate together. Each does its own work. The same work differently? Different work in the same way? This subtlety was tantalizing to puzzle out, as I moved among them. Divided between two rooms in the studio, much as they will soon be divided between two rooms for exhibition, each painting seemed changed, whether faintly or wildly, each time I approached it. In this way, memory does come into meaningful play: one terre verte surface in the front room might prove exceedingly similar to one in the back room, but to surmise such, I can only rely on the presumed mutuality of my own observations and recollections, shifting between them just as I shift between spaces, just as I shift between paintings; and just as qualities of light or atmosphere shift between spaces, between paintings, too.

Marden began these works as a group of eight, adding two more canvases in part because he had room to do so. They now feel uniquely suited in both scale and number to this studio, and he anticipates a peculiar emptiness upon their pending departure. Yet these do not encapsulate terre verte, either—terre verte’s potential may well linger for Marden once the paintings have moved on. After all, the fundamental implication that each of them harbors, individually as well as together, is that terre verte might only manifest differently—might only define itself with a difference, however minute and mercurial, every time.

I felt some wistfulness, myself, leaving the unfinished works that afternoon, knowing that another two or three coatings of paint would render them effectively unrecognizable. Marden acknowledged that to remake these paintings a decade from now would surely demonstrate inevitable variations in the manufacturing of each brand’s terre verte over time. But the current suite of works already demonstrates the unfixedness even of earthen, grounded terre verte; and so my wistfulness was cut by curiosity, my keenness to meet the finished paintings some day soon, and to seek in their surfaces some sense of how or whether they are finished at all.