Time flows down Powhatan Creek

Powhatan Creek Bald Cypress
Venerable Bald Cypress growing in Powhatan Creek

Time flows down Powhatan Creek

As I lowered my kayak into the creek, I knew the water wasn’t the same as before, nor am I the same man. Hardly an original thought. People have pondered the river as a metaphor of time for umpteen centuries, probably even before Heraclitus.

I paddled as far upstream on Powhatan Creek as a rising tide allowed my draught to avoid obstructions in water the color of brown tea from the swamp’s infusion of tannin.

Letting imagination drift in headwaters cast me back to before the infant colony of Virginia when Native Americans chose waterways to navigate the coastal plain. As the creek narrowed, I passed under overarching branches, swamp rose and blooming cardinal flowers beloved of hummingbirds. Water rose ankle deep over the feet of Tupelo and Chestnut Oak trees. Bald Cypresses, the iconic trees of southern swamps, still bared their ‘knees’ as ramparts against hurricanes.

After resting my paddle to enjoy stillness, an Orchard Oriole sang and a Pileated Woodpecker laughed. A Green Heron stalked the margins and a Prothonotary Warbler flitted across the stream, perhaps the last golden flash of the season. Turtles hauled onto logs to sun themselves in dappled sunlight and beavers left evidence of their presence on gnawed tree stumps.

I found a place to turn for taking the current as the tide changed, conveying youthful water downstream where it empties into Sandy Bay and washes around Jamestown Island before dying in the mighty James River. When the creek widens to meander between mudflats I know I have reached early middle age. Beds of pickerel weed and arrow weed dangle seed pods and wild rice reach above the green blanket for birds to glean, no longer plucked by the Powhatan tribe.

After paddling for a mile, I greet an old friend where kayakers from the James River Association stopped to stare. No one knows the age of the gigantic Bald Cypress standing on its own little island. Resurrection Fern clothes some boughs, an epiphyte that can revive from countless cycles of dehydration. I feel a fragile, mortal creature beside this mother tree and her foster fern.

The cypress was already elderly when Pocahontas and Captain John Smith paddled here over 400 years ago. Famously strong and slow growing, the rot resistance of this species makes it prime lumber. Outstanding in every way, male or female and the only one of its kind to shed fall leaves, its green mantle turns russet before winter when it stands among other bald trees whose lives retreat inside the wood like beavers hibernating in their lodge until spring calls.

We shall never know how many seasons and what history the tree has witnessed. A storm long ago tore off a side from its massive bole, losing the rings that recorded its antiquity. Perhaps it is the oldest in the eastern USA, though the official record is held by a Bald Cypress in the Black River of North Carolina, a spritely youth when Daniel prophesied, and still waits for the Apocalyse.

When I join midstream the retreating tide carries me through a changing landscape. Vegetation that thrived at the start of my journey cannot tolerate saltier mudflats. But far from barren, cord grass and fiddler crabs abound, frogs croak and an osprey plunge for a bass. I love drifting in these middle reaches, wishing they had no end.

Next Post: Songbirds Taste Sweet

Cherry blossom time

Our Weeping Cherry tree started to bloom on March 28, an old lady now yet still graceful. She has a voluminous floral dress spread wide from her ‘hips’ by branches like the hoops and side panniers of a woman in the court of George III. She cheekily displays through the cascade the one silvery leg she stands on. We hope she dances in the spring breeze for more years.

The same day, the National Park Service announced the famous lines of cherry trees lining the National Mall reached peak bloom. Fewer people stroll there in a pandemic year but can view them at #BloomCam. This year the blossom that celebrates beauty and grace is a brilliant contrast to the chaos and violence viewed from the Mall of the Capitol steps on January 6. But it also symbolizes the impermanence of life.

The trees were gifted to Washington DC in 1912 by the Japanese, who celebrate bloom time with spring festivals (hanami). This year the peak occurred in Kyoto on March 26, earlier than usual, as in the Mall. Bloom times have been recorded in Japan for 1,200 years. The date varied depending on when winter lost its grip, but on average stayed constant over centuries or rose slightly until the 19th century since when it has steadily advanced.

The ancient recorders of first blooms and shoots could not imagine why they should interest us today. But there are no more blazing signs of a  warming planet than trees exploding in color. On March 28, Red Maple buds burst at Mechanicsburg, PA and Pawpaw at Gibsonville, NC, although Redbud is still dormant at Spring Hill, TN (already rose pink here in Williamsburg, VA). If you doubt our climate is changing, ask the trees.

Shelterbelt Trees in Snow and Fog

Have you noticed how trees hollow out melted sleeves from snow around their boles as our arms would if we could hold them long enough in a snow blanket? And have you wondered why winter fog sinking over open fields is denser than in adjacent woodland? I never gave them much thought until a recent winter walk, but isn’t it often so that the familiar and banal is suddenly thrust to attention to look fresh and strange?

The brain suppresses absorption with too much detail until the detail becomes important or something or someone points it out. I can’t put my finger on what drew my attention to melting snow and thinning fog one day, and it wasn’t more important than the other stimuli bombarding my sense organs. Most noise is filtered out in the conscious brain to avoid being swamped and making us go crazy. But looking intently at something commonplace for the first time can stir uncommon curiosity.

Almost everyone prefers a simple explanation to an obscure one, which is the wisdom of Occam’s razor. When I had students in class they loathed to hear me say: “I have several hypotheses to offer for this observation, and there is evidence for all of them …” That was a way of admitting ignorance without sounding ignorant. Nature is more complicated than we are sometimes wont to admit or accept.

Foggy morning at Jamestown Island

We are drawn to the single explanation, but when we look more closely and are better informed we often find two, and on even closer examination we realize there are four, and then we begin to wonder if we’ll ever get to the bottom of the mystery. We are tempted to turn back to simplicity and turn our backs on provisional knowledge to cling to intuition. I don’t believe in fairy stories, but I know the temptation to be willfully ignorant and it must be resisted.

There is a bottom to the pit of curiosity, a place where facts are finally robust against doubt, but plumbing the depths can take a long time, even generations of science and philosophy. If we boast about our knowledge we fool ourselves because science is still young. Besides, isn’t mystery something to celebrate except when it holds down human welfare or harms our environment (basically the same things)? Mystery is a call to act and understand and is often more intriguing than the mere appearance of knowledge, and perhaps that’s why it is so popular in fiction.

I started musing about snow crystals melting around trees and foggy water droplets vanishing in shelterbelts. Why do they?

Elementary physics offers an easy first answer to my sudden curiosity. Tree bark absorbs some radiant energy, especially the darker shades, even on a cold day when we hardly feel heat of the sun on our faces. It may seem too trivial to change the physical state of water in snow and fog, but the heat stored by day is slowly released to help a slow thaw continue at night. The scientist wants to test a bare theory by experiment. Next time it snows I will check a natural experiment by comparing the melt around maples and oaks with the lighter boles of silver birches, which should in theory remain snow-bound longer.  And here is another question for an inquisitive walker. Does snow melt as quickly on rocks as tree trunks of the same color, and if not why the difference?

A second explanation is that trees offer shelterbelts against chill winds. More heat is lost by radiation from open ground on cold days and freezing nights than among trees, which also reduce wind velocity to stabilize a warmer zone. If you ever get stranded on a bitter night in the countryside it’s wise to find shelter in woods. But it’s hard to see how shelter accounts for melted ‘sleeves’ of snow around trees.

Casting around for other explanations, I wonder how much heat is generated by the thin cylinder of living cells under the bark when trees are looking dead in winter. To be alive is to be engaged in combustion because heat is the by-product of metabolism, generating 500 kJ per mole of oxygen when complete, to be precise.

It seems unlikely the low ebb of metabolism in sleeping winter trees warms the snow, and heat is more likely to be generated on tree bark than under it. To think of microbes and fungi is to remember hot compost and sweaty manure, as well as bubbles of carbon-dioxide popping in the air trap of a home brewer’s dewar. They can be sources of prodigious heat, and commercial breweries sometimes struggle to keep temperatures down.

Tidewater Virginia is marching toward spring and unlikely to see more hard weather so my questions about silver birches and rocks will dangle until I am trudging through snow again next winter.

Next Post: Snow tracks

 

%d bloggers like this: