Taxodium distichum (including T. ascendens and T. mucronatum)
(Taxodium means, roughly, resembling Yew. Distichum means “two rows.” That is how the leaves are, usually.)
You may now think we’re going to skip down Bald-Cypress Knee Lane, but no, been there done that. Today it is about Bald-Cypress underground. Not that it is easy to know much about its hidden subterranean (or submarine) life, given the pesky overlying water and mud pudding guarded by cottonmouths. Yes, I met one recently researching Bald-Cypress (I was researching the tree too).
You ever wonder why Bald-Cypress trees almost never topple, despite living with shallow roots in jello? They form a huge woven mat under the mud. This explains two things: 1. Even hurricanes don’t push them over. 2. It is hard or sometimes impossible to match roots to individual trees. The way the roots work, how they transport air at least 25 feet horizontally under mud and water, is to this day still mysterious. Arguably the best case for air exchange is through dead but still-intact water-conducting cells repurposed and re-filled with air. UF former doctoral student Helen Fisher several years ago conducted experiments on this ventilation system for Slash Pine roots, and suggested the same for Bald-Cypress. So far nobody has taken the bait and conducted a modern study on this suggestion. Why? Repeat: those roots are IMPOSSIBLE to access.
Speaking of swamps, let’s start with Washington DC. The heart of the nation’s capital floats atop a former Bald-Cypress swamp discovered during building projects in the 1920s, and dating back perhaps 100,000 years, with stumps still persisting 20 feet beneath the lobbyists and legislators. Some of those stumps are 8 feet in diameter and 1700 years old when they were buried.
Maybe those old DC Bald-Cypresses were Mastodon food. In Florida Mastodon Dung is preserved to this day in deep cold water in the Aucilla River. Guess what the main ingredient in the Mastodon droppings is: masticated Bald-Cypress.
Actually 1500 years old is a baby. There are Bald-Cypresses alive today in the Carolinas up to 2600 years old. That boggles the mind….the trees came into existence about the same times as the Hanging Gardens of Babylon. Their annual rings are useful for comparing ancient growth patterns over time, for example to check on climate changes from ancient times through the Industrial Revolution to present times. Twenty-six hundred years is old, but younger than a famous Bald-Cypress no longer standing due to a fire in 2012: The late “Senator,” right here in Florida, was a BC around 3500 years old. Now that’s BC!
Some Bald-Cypress is put underground on purpose. Ft. Jackson guarding the Mississippi near New Orleans is a prominent example. How in a swamp in the 1820s did you build a stout brick fort able to withstand Civil War bombardment and two centuries of hurricanes? On a solid foundation available on site. The fort rests on, you guessed it, the indestructible wood of Bald-Cypress. All still there, the fort and its underpinnings, although not in great shape.
Let’s wind up with linked stories of survival and utility. As Kansas biologists Benjamin Tremmel and Craig Martin described, a Bald-Cypress was planted in the 1870s in a ravine on the campus of Benedictine College in Atchison, Kansas. Around 1900 the ravine was filled in. The tree had half its trunk interred abruptly under the dirt fill. It rose anew. In 2000, a century later, new construction forced destruction of the still-living tree which had sprouted roots on the buried trunk like a gigantic “cutting” rooting over a century in plant propagation. This swamp dweller has no issue with sediments accumulating up its trunk! Aztecs in Mexico applied the same ability near present-day Mexico City. To expand flooded land in Lake Texcoco would normally have required building enclosures of vertical logs in the water, then filling in dirt. But the Aztecs found a better way…plant taxodiums crowded in a line like a picket fence, and they soon become indestructible rot-proof living seawalls oblivious to the fill dirt applied over their roots. There are still ancient taxodiums in the Lake Texcoco site dating back to Aztec horticulture. You can see some, and one of the largest trees in the world, a Mexican Bald-Cypress photographed and discussed by David Creech in his blog “Life on the Green Side”
As deplorable a loss to the natural world draining a Bald-Cypress swamp may be, and I’d never advocate it for research, when one is sacrificed for “The March of Progress,” wow, would I love to be first on the scene to see what goes on with those roots!