ecology

Swamp ladder, or step stool?
From highest to lowest

Big Cypress National Preserve is considered to be part of the greater Everglades ecosystem, but is also recognized as a distinct physiographic province even if the terms used to describe it — such as Western Everglades and swamp — fall short.

From highest (top) to lowest (bottom): mesic pines, marl prairie, outer edge of a cypress dome, interior pond apple center of a cypress dome,

What we do know is that you know it when you’re in it. In contrast to the Water Conservation Areas and Everglades National Park to the east which are dominated by the vast and perennially-flooded plain of peat-underlain ridges and sloughs (and dotted with tree islands), the Big Cypress consists of an interwoven mosaic of shorter hydroperiod wetlands. The Big Cypress also includes peat marshes, but is made visually distinct by its cypress forests – called domes and strands – which beneath their vertical apogee give way to orchid-hiding swamp forests and which at their fringes recede into a combination of open vistas of herbaceous marl prairies, fire-swept pinelands and scattered upland islands of hard-wood hammocks.

Its pattern of vegetation is commonly referred to as a mosaic and is a reflection of liliputian valleys and hills of the preserve’s flat and expansive wetland terrain. The difference between the preserve’s low-lying swamp and pineland high ground is only 3 feet.

I like to call it the swamp ladder. But maybe stepstool is more accurate.

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Safety Tip: Be careful on ladders of all sizes!

ecology

Seeing the mosaic
The art of drawing water

As much as I’ve tried,

Photos always seem to fall a little short.

Photo of the mosaic: From highest to lowest, the “swamp mosaic” pinelands (dark green), cypress (gray), marsh (yellow) and open pool (blue). Difference in elevation: about 4 feet

Not that they don’t tell a thousand words, they do. And sometimes even more (sometimes less). But still, whenever I take a photograph trying to capture the swamp’s mosaic, there’s always something that gets left out. Not that it stops me from trying. Whenever I fly, the pilot says to me: Didn’t take a photograph of that before. “Probably. Actually that’s a definite yes,” is my usual response. Even down on the ground in front of what some would say is a not-so-scenic monolith of concrete better known as a water management gate, I can’t seem to photograph it enough.

Diagram of the mosaic

That’s where diagrams come in handy. You can pack in a diagram everything you couldn’t get in a photograph, even in a helicopter at a thousand feet. As for which is better? I like a combination of both. I’ll continue to take photos and draw. And know, I’m not a photographer (a paid one) or an artist (to be debated, but yes, also unpaid), but I am a hydrologist. The truth about hydrology is that taking photographs and drawing sketches is all part of a days work.

Swamp of inches
High and low ground explained

Small variations in land elevation …

Translate into large variation in plant composition.

Can you see the high ground? Hint: It’s green.
Here’s a closer look at a pine island
Water is retreating into the lower-lying domes

A vertical range of just 2.5 feet differentiate the Preserve’s major vegetation communities.  More than the Everglades which is mostly buried under peat, differences in elevation, hydrology and plant communities in the Big Cypress are related to undulations in the underlying bedrock (Lodge, 2010).  The underlying bedrock is irregular, and both exposed at the surface and buried by as much as 10 feet of soil and organic matter.  Hammocks and pinelands are typically found where bedrock is at or near the surface.  Cypress strands form where bedrock undulations are deepest and marshy sloughs where bedrock undulations are shallower. 

Rolling Swamp
And why the canopy doesn't lie

Swamps are flat and low …

Making it impossible to see a good view, right?

Big Cypress National Preserve’s Mullet Slough

That might usually be the case, but not in the Big Cypress Swamp. The reasons? The swamp ecosystem is full of mountain ranges of linear-running cypress strands and rolling hills of cypress domes. And yes, those strands and domes are actually places where the land dips (and water stays longest), but the canopy couldn’t be more clear: the swamp is a uniquely undulating terrain. And it’s not just from the sky that you can see the effect. The best vantage is probably best from the ground, in a marl prairie where the vista to the horizon is clear and the distant mountain ranges (strands) and hills (domes) abound. Or is the better view from the domes and strands themselves? Walking in the trees are dense at first, until it opens up and there you are — at the bottom of the tallest trees (the mountain tops) looking up.

More about the photo above: The deepest spot is the hole where there are no trees. As for the highest ground, that would be the green area in the middle that looks lower than everything else. The land in there is called a hardwood hammock and is actually dry all year round compared to the rolling (and flooded) hills of cypress around it.

Optical illusion swamp
Where appearance and reality morph

The swamp is full of optical illusions …

Or do they actually reflect a deeper reality?

Photograph of optical illusion no. 1

Take for example the oval groves of cypress trees called domes. They look like hills, but they are actually the low spots in the swamp. It’s the adjacent pinelands (foreground) that mark the high and dry ground. But the domes are also where water depth is tallest. So if you’re a fish or a bird or an alligator, the tallest depth of water coincides with the center of the hill-shaped domes.

Narrated video of optical illusion no. 2

Then there’s the case of the optical illusion you see in a helicopter flying over a fully flooded swamp. The reflection from the below reveals the strange effect of trees moving at a fast clip backwards and the mammoth clouds staying put (see video above). Of course, in reality we know it’s the clouds that are on the move (from hour to hour and day to day) whereas the trees are rooted down in one place. But over time, as the years and decades pass, the forest below is in fact on the move. Habits shift, retracting and expanding in, in response to the seasonal dosage and return interval of flood and fire on the landscape.

I‘m not saying that optical illusions are right or wrong. All I’m saying is that they hint at the deeper reality of the swamp.

Swamp’s falling foliage
And why it bests the fall "leaf change" up north

In the summer swamp, everything is green.

That gradually gives way in fall to a study in black and white.

The swamp mosaic turns green and gray during the fall, helping make it visually pop. But is it as scenic as the “leaf change” Up North?

Well, probably green and gray is a better way to describe it. Slash pine and cypress comprise the majority of the swamp, and in some places are pretty much all you see. While a connoisseur of the Big Cypress landscape can easily differentiate the cypress from the pines during the spring and summer half of the year (and for the more botanically inclined, all the other green-leafed trees, i.e. gumbo limbo, pop ash, willow and pond apple to name a few): It isn’t until mid October with the browning and then falling of the cypress needles that the boundary lines between cypress, pinelands, prairie and hammocks really start to pop.

While I may be biased, and don’t get me wrong I love the summer clouds — There’s just something super scenic about the cypress losing their needles and turning gray. Partly it’s the contrast to the perpetually green pines, but it also has something to do with the abundance of water still on the ground. October is high water season in the swamp.

The mosaic is more than just pinelands and cypress. As shown above, taller cypress domes are separated by a sea of dwarf cypress and dotted by hardwood hammocks as shown in the foreground

Everyone raves about the fall foliage in the deciduous forest of the Northeast, but we can’t forget that cypress is a deciduous (albeit also a conifer) tree, too. South Florida may not have your traditional “leaf changing” season of multitudinous orange, yellows and reds. However, the cypress needles – by browning and falling – put on an autumnal show all their own. Better yet, it lasts quite a bit longer, too — for four months all the way to February.

But to see it in its most glorious form, you need to see it when the water is still up. Disclaimer: This may involve getting your feet wet. Water is shin to knee deep depending on where you walk in the swamp.

Fall foliage along Turner River road, looking north. Can you see the open marl prairie in the distance towards Upper Wagon Wheel Road?

In sum, for me, if I had to chose: When it comes to the autumnal foliage event, I’d take the swamp’s “falling of the needles” over the continent’s “changing of the leaves” every time.

Full disclosure: My proximity to the swamp probably sways my opinion (to a degree).

ecology

Multitudes of green
Swamp mosaic starts to pop

How do you best describe …

Every shade of green on the swamp?

The cypress will turn brown then gray in the weeks ahead

The term is called the swamp mosaic. Bright green are slash pine and palmetto. Dark green is a hardwood hammock. Brownish green are senescing cypress. It’s a bit of an optical illusion looking at the photo above. The highest ground is actually the hardwood hammock, even though it looks recessed. And the lowest ground is the cypress strand despite its appearance that it is higher up. Actually, I take that back: Even lower than the cypress is the open pond to the right. I would venture a guess that’s about 4 feet deep, about half the depth of the water in the adjacent cypress and the hammock being completely dry. And I almost forgot. About mid photo, a little to the right, is a marl prairie. It’s flooded shin deep with water.