Marcescence

“When great leaves fall, the winter is at hand…”

–William Shakespeare, Richard III, Act II, Scene III

But some leaves don’t fall. They hang on to the branch tips like mittens on idiot strings, waiting for spring buds to snap them off.

This phenomenon in nature is called marcescence, defined as the withering and persistence of plant organs that normally are shed. On our farm, it is found mostly in oaks, but you’ll find it in leaves and fronds of species all over the U.S. 's 13 hardiness zones.

I became interested in marcescence because of my new city garden witch hazel tree.

The non-native pink crepe myrtle which preceded it got black sooty mold. Treating it didn’t help and anyway I wanted an excuse to plant a native. I already had plenty of spring color in the garden and was looking for a late summer- to fall-bloomer when I found Hamamelis virginiana, a North American witch hazel. Growing to 15-25 feet and known sometimes as winterbloom, its cheery yellow foliage said “Choose Me!” It looked like it would survive, maybe even thrive, in my soil and light conditions. It only needed extra water to get it going, and after that could do quite nicely with average rainfall.

Already it’s a three-act play. The five-foot sapling with its kelly green leaves arrived in early May. On cue it produced handsome yellow foliage in October. The alchemy of winter turned the golden leaves to copper curls hanging on to the branches.

But there is a fourth act. In the D.C. area where we live, it’s all about the cherry blossoms. Each year in late March the National Park’s 3,800 cherry trees drape themselves in pink bunting that after 10-14 days drops in a pile on the park’s walkways.

Six years from now, our witch hazel will put on a festival to rival this. In October among the yellow leaves on the dark gray stems will appear a flower.

Starbursting out from a red Victoria cross center, four corrugated petals like strips of shredded yellow construction paper will be on show through December. Their inviting scent crosses allspice with honey. That should knock the pink stuff right off the podium.

Normally, bare branches make me impatient for spring glories. Marcescence has given me a new view. It’s beautiful to see these brown leaves against a bluebird sky. It’s comforting to hear them talking all at once in a clatter, a rustle, or a whisper, depending on the force of the wind.

Swedish explorer and botanist Pehr Kalm, a disciple of Carl Linnaeus, noted marcescence back in 1749. But no definitive cause has been found, and there is little study of the topic. (If I were a budding dendrologist I would own this.) Researchers have six hypotheses:

1. No reason–just a byproduct of evolution

2. The retained leaves wave off those pesky herbivorous winter browsers, making it tougher for them to nibble the buds

3. During fall die-off the retained leaves help nutrient resorption (kinda like absorption but not)

4. Dropping leaves in spring v. winter hoards nutrients and encourages decomp

5. The retained leaves keep the hopeful buds from freezing or drying out

6. (And this would make one of those great laminated flow charts) The canopy of retained leaves invites insects, birds, bats, etc. to move in for the winter such that their poop creates a Fort Knox of nutrients for its grateful host.

To make any of these theories work, some biochemical drama has to happen. The cast includes the free-flowing hormone auxin, a waterproofing phenolic polymer called lignin (like the stuff you paint on your basement wall, only brown), and cork-y cells full of suberin, another polymer popular in roots and bark. Basically in fall these Machiavellians say to the marcescent leaves, “Please please don’t go!” and then, come spring, “Here’s your hat and there’s the door.”

Instead, I favor a story from the Seneca Nation of the Iroquois. Basically the tree version of a tribal council was convened by The Conifers to figure out how to be Winter Strong and defy the itching-for-a-fight Spirit of Summer (and apologies in advance if I’m mangling this). Worthy aspirants including the oak, beech, hornbeam, and musclewood lined up for a magic elixir that would guarantee yearlong greenery (Take THAT, SUMMER!!). But when the Pine Priest got to them with the cup the elixir had run out ( “Sorry, guys!”). Snubbed, instead of walking over to join the leafless maples and their naked pals, the ragtag band–soon to be known as The Marcescents–raised their shriveled brown leaf fists to the April sky, defying not only a chastened Spirit of Summer but those cheatin’ Pines.

For a relatively unheralded phenomenon, marcescence does seem to prompt a lot of poiesis. Arboretums and extension services have produced illustrated articles titled “The Mystery of Marcescence” and “When Oak Leaves Fail to Fall.” A poem by Gilbert Allen, “Marcescence in March,” appeared in the 2018 Fall/Winter issue (of course) of Appalachian Journal.

I think this is because one cannot help thinking there is marcescence in humans. When the snowbirds flock to Arizona and Florida, some Northern peoples conspicuously remain in their tundra. No fall abscission for them! Out of the cabin they go, Sorel-ing the frozen lake with their Home Depot plastic pail and Bass Pro Shop reel and ice auger clutched in their Carhartt-mittened hands. Maybe they are the legatees of our prehistoric selves, who, out hunting and gathering on a wintry day in the savanna, sought the comforting conversation of the tall oak’s dried leaves.

On the farm, I’m now thinking about using trees with this attribute to replace the usurping autumn olive. The retained leaves could provide cover for critters in winter, and their spring-dropped husks could mulch the eroded stream banks.

Marcescence makes a cameo in my own story. If I had not clung season after season to my dream of land, I would not be writing this now. I remember In 2020 seeing painted on sheets in neighbor-activist's windows the imperative “Resist!” My version: On a large, slightly battered, definitely desiccated brown oak leaf I inscribe in (semi-) permanent marker the lone word:

Persist!