A Journey through time in Kaaterskill Clove

The Catskill Geologists – The Mountain Eagle; 11-3-17

Robert and Johanna Titus

Have you ever hiked the north rim trail at Kaaterskill Clove? It’s one of those many great experiences that anyone living in the Catskills should have done – perhaps, like us, many times. Better still, it’s something you should take visitors to see. When we go there, we stop at Inspiration Point and look down about a thousand feet or so, and gaze into the distant past. Way down there, about 15,000 years ago, was a raging, foaming, pounding, thundering, whitewater torrent. Those were the waters of the melting glaciers of those late ice age times. That flow did most of the work of carving Kaaterskill Clove. That’s what makes this truly a geological wonder.

But there is still an older time, represented down there. Down in the very depths of the canyon, there are stratified sandstones and shales. The canyon is about a thousand feet deep here, so there must be an equal amount of stratified rock. Those rocks are middle and late Devonian age, which makes them about 385 to 375 million years old – that’s in very round numbers. It’s natural for geologists to ponder such vast numbers. We are pros; we are professional scientists, and we are not supposed to wax poetic about such things, but – we can’t help it.

The two of us began to wonder just how many years had passed by from when the oldest strata, at the bottom of the Clove were deposited, to when those at the top came to be. We got out some publications from the New York State Museum and began to make some “guesstimates.” We are only going to make some gross approximations today; so don’t hold us to any of our numbers. We just want to give you a notion of when all the stratigraphy at Kaaterskill Clove came into being, and how long it took to be deposited. If somebody thinks they can come up with better numbers, we welcome them.

We think the strata at the bottom of the canyon belong to a unit of rock called the Plattekill Formation. The Plattekill is a unit of gray and brown sandstone. The New York State Museum places the middle Plattekill at about 385 million years in age. We think the top of Kaaterskill Clove corresponds with the top of the Oneonta Formation, a largely red sandstone, and that makes it about 381 million years in age. The math is pretty easy; we get about 4 million years of time represented from the bottom to the top of the clove’s stratigraphy. Remember those 1,000 feet that the canyon encompasses? Well, we divide through and we get about 4,000 years per foot of stratified rock.

Now, none of this is great science, and none of it is great math. A foot of river sandstone might have been deposited in a few hours. A foot of red shale may have taken many, many thousands of years to form. There must have been sediments from vast expanses of time that were eroded away and lost forever. Other great lengths of time just never saw any deposition at all. But, we think we have come up with some reasonable approximations and that is all we are aiming at.

Again, stand atop Inspiration Point and look down those thousand feet. See 4,000 years of time for every foot below you.

Contact the authors at randjtitus@prodigy.net. Join their facebook page “The

Our reader’s rocks – Ice in Grand Gorge Gap?

The Catskill Geologists; Robert and Johanna Titus

The Mountain Eagle; Sept.15, 2017

We always give our email address at the bottom of each of our articles. And we can always be approached on our facebook page, so we hear from a lot of our readers. Often they have questions and we are usually able to help tem with answers. Every once in a while, we thought we would answer one of these queries in the form of a column so here goes the first.

Recently we heard from a Gerry Hubbard. He sent us a photo of Grand Gorge Gap and wanted to know what the rounded hump on the right is. Take a look at our photo and you can see that hump. We had been wondering the same thing for years and so Gerry’s request got us to do something about the problem.

The first step is to get our topographic maps out and look at them. We found that the Roxbury 7 1/2 minute quadrangle map displayed the Gap. We found that the hump has a name; it is Jump Hill. Then we went back to our photo. The “hump” is actually something that lies in between two valleys. The contour lines on our map indicated a steep but steady slope for each of the two valleys. Each one of those is what geologists call a U-shaped valley. Every trained geologist on the planet Earth quickly recognizes the ice age history of such a valley. They record the passage of glaciers. As ice squeezed through a valley it ground away and eroded the bedrock. The shape that offers the least resistance is the U. Not surprisingly, over a period of time, glaciers will carve those U’s into the bedrock landscape. It gives each of them a path of least resistance. That forms a remarkably picturesque image and that helps make glaciated landscapes so attractive. We geologist are most fond of these U-shaped valleys.

Well, we studied the map and our photo and started speculating about what had happened here, way back, near the end of the Ice Age. Speculation is a word that scientists like to avoid; it sounds so – well speculative. So we use the word hypothesize instead. It sounds better. We hypothesized the following story: We hypothesize that the larger U-shape, on the left, is the older of the two. We think that a sizable glacier entered Grand Gorge Gap and began eroding the large U-shaped valley. Somewhere along the line, the ice was diverted and a second stream of it passed through what is the smaller, and we think younger, U-shaped on the right. All this erosion left Jump Hill in between.

We hope that Gerry likes our hypothesis. It conjures up quite an image. We travel north on Rte. 30 to where we can park and see this view. In our mind’s eyes we can imagine the advance of these glaciers; we can watch them carve the shapes of Grand Gorge Gap. That view gives us a whole new perspective on this site.

We hope you enjoyed our hypothesis. Perhaps you have a location that we could write about. Let us know.

Contact the authors at randjtitus@prodigy.net. Visit their facebook page at “The Catskill Geologist.”

Why Gilboa? By Robert and Johanna Titus

The Catskill Geologists in The Mountain Eagle

Sept. 15, 2017

   Gilboa was, a century ago, a sizable town in the center of the Catskills. We have been told it was once as big as Cobleskill. But fate struck; New York City reached out and took the land the town was built on, and used that for a reservoir. A dam was constructed just a little west of the old town. The village was razed and, when the dam was filled with water, it disappeared altogether. What little is left, is at the bottom of the reservoir

It was a sad fate, and one which is still deeply resented. But, why did it happen? What was it about Gilboa that led to its demise? We decided to see if we could answer that question. We could not go back through time and travel to the offices where New York City engineers were making their decisions. We could not talk to them, or read their minds. And, much of the geological evidence is now hidden from sight, at the bottom of the reservoir. But, there are other sources of evidence. Perhaps we could read those minds!

We have one of the maps that those long ago engineers must have used. It’s what’s called a 15 minute quadrangle map of the Gilboa area, published by the New York State Department of Public Works. Ours is the 1903 edition, so it is the very one that those engineers were likely eye-balling as they searched for likely locations for New York City reservoirs. We could look at this map and think as they must have.

We have selected that part of the map that shows the Schoharie Creek Valley where it stretches from Prattsville, north to the onetime site of Gilboa. That’s where the reservoir went. Take a good careful look. Do you see all those narrow lines? Those are contour lines. They define different elevations. The bottom of the valley was at about 1,050 feet in elevation. If you look carefully, you can see the 1,050 foot contour line, just to the right (east) of the creek.
The bottom of the creek was valley floor flatland. It must have been good farming. Notice the absence of contour lines down there. Flat land has very few, or no contours. But the valley walls are different; there contour lines are closely spaced. A person who, back then, climbed up those slopes would have frequently crossed contours.

Experienced geologists can “read” such maps and learn so much from them. Well, we studied the map and began to see the Gilboa area as it had been, before the reservoir and its dam. We saw that most of the valley floor, all the way south to Prattsville, had been wide and flat. We know that this had been the bottom of something called Glacial Lake Schoharie, and those flatlands must have been lake-bottom silts. Easy to plow, these acres must have been wonderful farmland.

But look where Gilboa was; there the contour lines crowd the valley floor. That’s where the Schoharie Valley had been surprisingly narrow. Those long ago engineers must have seen the potential. Gilboa was located right where the valley was narrow and easily dammed. Behind that planned dam, was a wide valley with a flat floor.

The Gilboa site was ideal for damming; the lands behind that dam would be perfect for a reservoir. Gilboa’s fate was sealed; the town was doomed!

Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.”

A visit to Glacial Lake Windham

The Catskill Geologists

Robert and Johanna Titus

The Mountain Eagle – Sept. 8, 2017

Last week we visited Windham, actually the Windham Path, just east of town. We wanted to show you something about the ice age origins of the town. Most of the Windham Path lies upon the floor of what’s called a glacial lake. That lake had come into being when a glacier deposited heaps of sediment in something called a moraine. The moraine can be seen just east of the Path. Most of the land from east Windham to here is rolling elevated moraine landscape. That’s the land lying just east of Mitchell Hollow Road.

Let’s learn some more this week. We would like you to drive west from Windham on Rte. 23. You may have done this before, perhaps many times. But, as always, we want you to be paying more attention to the landscape that you are passing. We, especially, want you to take heed of the flat landscapes down at the bottom of the valley. It would be easy to dismiss this as a floodplain, after all valley floors are supposed to display floodplains. But, you would be wrong; this flat landscape is the floor of an ice age lake. Lake deposits are almost always spread out as flat sheets. That’s what we see here.

These lake bottom landscapes continue at least as far west as Ashland. They speak to us of a glacial lake. It was a big one, extending at least five miles from the Windham moraine to a bit west of Ashland. Rte. 23 lies on a platform that runs parallel to the old lake. That platform also has an ice age origin. It is composed of sediments that were dropped down the northern valley wall and deposited as a lakeshore deposit called a glacial terrace. That terrace was irresistible to highway engineers when they were making Rte. 23. It lifted the highway up onto a well-drained surface.

The top of the terraces was deposited at just about the old lake level. Our topographic map tells us that that level was at about 1,500 feet in elevation. The map also tells us that the lake bottom lay at about 1,450 feet. We can thus calculate that the lake was about 50 feet deep. It got a good bit deeper toward Ashland. Turn south (left) at Jewett Heights Road and, when you get down to the river, stop and get out. You are now standing on the floor of a deep lake! Have you ever done that before?

You might do a little exploring. Look for a vantage point, somewhere above the 1,500 foot level. Now you can look down and, in your mind’s eye, you can survey Glacial Lake Windham as it once was. We picked a day, very late in the Ice Age. The climate had been warming up considerably and the ice had melted off most of the lake’s surface. There was, however, still a narrow shelf of gray ice all around the lake’s shore.

We were hoping to see some animals. Perhaps a mastodon or two might have been walking the shores of the lake. But, we were disappointed. It was not that late in the Ice Age, it was still too cold in Windham.

Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.”

The Earthquake at Mexico City

The Catskill Geologists; The Mountain Eagle; Sept 19, 2017

Robert and Johanna Titus

For the second time in a thirty years, Mexico City has experienced an awful earthquake. It was actually about 75 miles southeast of the city; that’s close enough. This one measured about a 7.1 on the famous Richter scale. That’s a powerful earthquake. Early reports claim that 40 buildings came down and several hundred people died. We don’t have many earthquakes in our region, and when they do occur they don’t amount to much. Still, we can’t help saying something about it; it has been a big geological event.

Why was it so bad? Well, as we understand it, Mexico City lies within a series of very sizable geological faults. And they are circular faults; the crust has broken up into a series of concentric circles. These are also active faults; they generate earthquakes from time to time. That’s bad enough, but it gets worse. The basin that lies inside these faults has filled with lake sediments. These tend to be wet, and that makes them very unstable during any earthquakes. The seismic waves pass through the sediments and they become liquefied. Mexico City finds itself shaking on a liquefied landscape.
That accounts for a lot of the damage.

We have found a way to demonstrate this. We like to get a thick pint glass out and fill it to the very top with water (beer when Robert is pouring). When the fluid is at the absolute top, we are ready to go on with our “experiment.” We pound a fist right next to the glass and watch the water at the surface. Most of the time we see waves radiating inward from the outer edge of the glass. Something very much like that happens to the Mexico City basin. Perform this experiment in your own home and then imagine the results scaled up to the size of a great city. Now, you understand what happened the past week.

The news is not all bad. These awful events present architects and engineers with wonderful opportunities to learn how to design earthquake resistant buildings.
That’s what happened in 1985, after the last big earthquake in the city. In the months and years that followed, experts studied the buildings that had come down along with those that survived. What, they asked, were the differences? How could new buildings be constructed so as to minimize the threats.

We will give you one example. Mexico City architects found that L-shaped buildings were very likely to collapse during a quake. One side of the L vibrated in one direction; the other half vibrated differently. The competing stresses brought those buildings down. They looked good but they were dangerous. Well, when these buildings were replaced, architects knew better than to use L-shapes.

The long and the short of it is that the rebuilding of Mexico City benefitted from the 1985 experience. Now all those earthquake resistant building have been tested by a new quake. We expect that at this very minute engineers are toting up the scores. Which buildings “won” and which buildings “lost.” Which of the new designs had succeeded and which didn’t?

This is progress, but it is a very expensive way to learn.

Contact the authors at randjtitus@prodigy.net. Join their facebook page “The
Catskill Geologist.” Read their blog at “thecatskillgeologist.com.”

The Ice Age at Windham – Part one, an introduction

The Catskill Geologists; The Mountain Eagle Sep. 1, 2017

Robert and Johanna Titus

We understand that we have a number of new readers in the town of Windham and we are glad about that. Let’s begin today a series of articles about the ice age history of that town. We can start at the relatively new Windham Path, located in the Batavia Kill Valley about a half mile east of town. It was opened about four years ago and offers some pleasant and easy walking.

Take a look at our photo. Most people see an inviting place for recreation; naturally we see geological history. Our photo was taken from the path’s parking lot. If you go there we would like you to look straight ahead into the distance. Notice the broad flat surface on the distant right of our photo. Now take a look to the left. Our picture shows a low tree-covered hillock spread out east of those flats.

Most people just see landscape; let’s learn what the two of us see. That hillock on the left is what geologists call a moraine. That’s a heap of earth that was brought to where you find it by an advancing glacier. We look at it and, in our mind’s eyes, we see a glacier advancing from the right. It is advancing because the climate had been getting colder – cold is good for glaciers, right? But by the time our glacier reached the left side of this view, climate change had begun; it started warming up and the glacier began melting away – retreating to the left.

During its advance, that glacier had been bulldozing large amounts of earth, all of it piled up at the front of the ice. But, when the glacier was melting away, all that earth came to be left behind. That’s a moraine; this heap of earth speaks to the two of us of an important chapter in the ice age history of Windham.

What happened next? The retreating glacier was backing down the Batavia Kill Valley. It acted as a dam and that formed a glacial lake, lying between the retreating ice and the moraine. It’s the sediments of that lake that make up that flat lying surface in the distant right.

You might go there and do what we do. We always keep a barbeque skewer in the back of the car. We bring it down to flat surfaces like this one, and try to drive it into the ground. If, as we expect, we have found a lake deposit then the skewer will easily slide into the ground. If it doesn’t, it has hit a rock and it is not a lake deposit. Lake sediments are all silt and clay and don’t have rocks in them.

Well, we have seen the Windham Path as most people don’t. We gaze at it and we see an ice age landscape; we form visions of what it was like here at the close of the Ice Age. It can be an exhilarating experience.

But it is important to take this information and use it to form a broader picture of ice age history in the Batavia Kill Valley. Let’s get back in our car and head west on Rte. 23. We notice, right away, that we are crossing an elevated landscape with rolling and sinuous hillocks. This landscape continues until just past Mitchell Hollow road at the eastern end of the Windham business district. We have found another moraine and this one is a bigger one. Like the one at the Windham Path it speaks to us of a glacier advancing east through the Batavia Kill of long ago.

We have learned a lot about Windham, but we have a lot more ahead of us.

Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist” and read their blog at thecatskillgeologist.com.

Time lines

The Catskill Geologists; Robert and Johanna Titus

The Mountain Eagle; Aug. 8, 2018

Late at night in geology bars, we geologists ponder deep thoughts about what geologists call “deep time.” We would like to relate some of those thoughts to you in this week’s column. It’s an account of what we visualize when we drive south a few miles from Middleburgh on Rte. 30.

Any time of the year this is a scenic drive. Left and right, we pass beautiful agricultural fields. This is a remarkably flat landscape and much of it is fertile land; it has been farmed for centuries and all farmland is pretty. Then there are several scenic hamlets, including Fultonham and Breakabeen. We like to sometimes stop at the farmer’s markets along the way. This is the modern world that we are traveling through, and Rte. 30 provides a very nice view of it. Autumn is coming up; you should take this drive

But, we are geologists, and we are always finding ourselves in the distant past. Did you read our recent column about this area? Then you know some of what we see when we do this drive. We related how this stretch of the Schoharie Creek Valley was once the bottom of an ice age lake. That was, perhaps 14,000 years ago when the ice age climate was warming up and the glaciers were melting away. We learned that this lake was hundreds of feet deep back then. If Rte. 30 had passed across that lake bottom then it would have been a pitch black road.

The next time you are there, stop and take a look around. We like to say that we are able to “savor” time at places like this. This broad flat valley floor has two manifestations in time. It is the world we see and that same flat surface was also the bottom of a substantial lake. This flat landscape has led at least two lives. You can imagine the thoughts this generates in a geology bar.

But, there is actually a lot more. When you explore the area, here and there you will encounter stratified bedrock. These exposures are mostly sandstones and shales, and it is not unusual for them to be rich in the fossils of marine shellfish. There are some substantial outcrops. One is at Vroman’s Nose. The next time you climb that “nose” watch for outcrops of stratified rock along the way. Drive south again and watch for more exposures along the way. It’s the same thing; those strata are frequently rich in fossils.  Each stratum was formed on the bottom of a sea. It gets better; each stratum was the bottom of a sea.

Perhaps you are getting the drift of today’s column; we have been describing a single flat surface that extends south from Middleburgh. It is a surface that exists today and, in this form, it is a very scenic location. But there is so much more. This surface has existed several times in the distant past. It was, 14,000 years ago, the bottom of an ice age lake. It was just as flat then but under hundreds of feet of glacial meltwater.

Then there was that third time our surface existed. About 370 million years ago it was the bottom of a saltwater sea. Geologists call landscapes like this “exhumed.” As such they are landscapes that reveal episodes of time from the very distant.

We hope you will enjoy this ride in the country during the coming leaf season. Pull over, get out of your car and “savor” our geological history.

Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist,” or read their blog thecatskillgeologist.com.

The Catskills: mountains or a plateau?

The Catskill Geologists

The Mountain Eagle

Robert and Johanna Titus

One of us, Robert, once suddenly began receiving hordes of emails from the students of an eighth grade middle school class. Each message claimed that he, Robert, had made a bad blunder in referring to the Catskills as being mountains. Each of them “corrected” Robert by pointing out that the Catskills are actually a “dissected upland plateau.” Their teacher had assigned them to do this. He wanted to know how Robert would respond to having been shown to be in error. Needless to say, this was annoying. It is, however, a commonly held notion that the Catskills are, on the basis of some narrow technicalities, not a range of mountains, but a plateau that has been lifted and then eroded, or dissected, by numerous streams, hence a dissected plateau. Let’s deal with all this in today’s column.

English is a wonderful language, well suited to describe the distinctions between all sorts of ethereal concepts. Typically, it is possible to use a choice of several words to describe the same thing. The words mountain and plateau are examples. The two terms grade into each other, but are defined in the Glossary of Geology, published by the American Geophysical Society (AGI). These are thus as close to official as such definitions can get, and they give plenty of guidance and also considerable leeway in using the two words.

The AGI definition describes mountains as being, first of all, taller than hills, usually rising more than 1,000 feet above surrounding lands. Equally important, mountains have restricted summits. They have steep slopes and considerable exposed bedrock. Perhaps most importantly, they are distinctive enough to have individual names. That last point is subjective, but critical.

Plateaus do not have restricted summits; they are “comparatively” flat areas “of great extent and elevation.” A plateau’s “flat and nearly smooth surface” can be “dissected by deep valleys or canyons.” But in the end, it must have a “large part of its total surface at or near the summit level.” When we look at maps of the Catskills, we think that the valleys are so broad, and the summits so restricted that they just do not conform to the notion of a plateau.

The Catskills are composed entirely of nearly horizontal sedimentary rocks and some think that this makes them a plateau. But the AGI definition does not prohibit flat-lying strata within mountains. Nor does it does it require them in plateaus. Those horizontal strata date back to the origins of the Catskills as a great flat-topped delta.

We travel the Catskill Mountains and see so many distinctive summits. Slide Mountain meets all the standards required to be a true and distinctive mountain. So do North and South Mountains, Overlook Mountain, Windham High Peak and so many others.
When there are a number of such mountains, the AGI glossary specifies that they can be combined under a proper name heading, such as the Adirondack Mountains.

But, beyond all of the above, there is an issue of elegance. English should, as often as possible, be an elegant language. Its words should flow off the tongue smoothly, they should also read the same way. We ask you: did Rip Van Winkle sleep for 20 years in a dissected upland plateau or in the Catskill Mountains?

Climb to the top of Slide Mountain someday this summer. Gaze out all around and decide for yourself: are you standing on top of a plateau?

Contact the authors, unless you are an eighth grade teacher, at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.” Read their blogs at “thecatskillgeologist.com.”

Looking into the future

The Catskill Geologists; The Mountain Eagle, 2088

Robert and Johanna Titus

We frequently travel about in the Catskills and we are always on the lookout to find a new topic for one of our columns. One day, recently, we were approaching Mt. Utsayantha from the northeast on County Rte. 14. On the mountain’s slope, rising in front of us, we noticed a fairly nondescript mountainside feature. Take a look at the left center part of our photo. You will see what is sometimes called a niche, That is, there is a depression in the side of the mountain.

Well, “so what,” you might ask, “big deal, what is there to get excited about?” And, you would be right; this is not an especially big deal; it is just a depression in the slope. But, we are geologists, and we are writers. We are always looking for an angle. After all, we have to send off a column almost every week.

We started taking this image and projecting it into the future, of course we mean the distant geological future. What, we wondered, would happen if another ice age came along? Our niche in the mountain would soon fill up with snow. And that would initiate a sequence of very predictable events, typical of the latest chapter of an ice age.

First that niche would accumulate thicker and ever thicker amounts of snow. Then the thickening snows, under the influence of their own weight, would start compacting. The snow would be squeezed down into a material that would resemble the packed snow of a snowball. Geologists call that material neve’. But, the process would not stop there; the compacting would continue until the neve’ would harden into genuine ice.

Once enough ice accumulated in the Mt. Utsayantha niche, it would start to become dynamic. Ice can flow like a great rigid mass of water. Its flow will be very slow, but it will move. It has become a glacier, in fact it has become an Alpine glacier, at least a future Alpine glacier.

We had slowed down but now, intrigued, we pulled over, got out and stared up at our Alpine glacier. Usually we gaze into the past but this time we found ourselves looking into the distant future. We had traveled to a time when the Catskills had come to resemble the Alps of today’s Switzerland.

When will this future Switzerland descend upon the Catskills? We don’t know; we haven’t gotten any of the ice age geologists, that we know, to commit to a precise prediction. But current ice age theory argues that glaciations occur in cycles that recur about once every 100,000 years. So don’t hold your breath. It gets worse; Alpine glaciers don’t form until late in ice age chapters. After all the ice, everywhere else, has melted away then the cold mountaintops become active and Alpine glaciers form.

That happened in the past. At the end of the last ice age, Alpine Glaciers formed atop the highest peaks of the eastern Catskills. The best example that we know of are found at North Point, near North Lake Campground and to the south at Overlook Mountain. Another very fine Alpine peak is Hunter Mountain.

But why didn’t Mt. Utsayantha develop some Alpine glaciers the last time? It may be that the mountain is just not tall enough. It reaches an elevation of 3,200 feet; the others are just a bit taller. So, sadly, Mt. Utsayantha may not be tall enough the next time. But, we can dream.

Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.” Read their blogs at thecatskillgeologist.com.

Tetraxylopteris

The Catskill Geologists; The Mountain Eagle; July 6, 2018

Robert and Johanna Titus

Tetra-what? Are we kidding? Well, if you have been able to read this far, we commend you. Our title is a one-word mouthful, isn’t it? But, here in the Catskills, this is something of an important word. It’s the genus name for a fossil plant that lived in Gilboa about 380 million years ago, during the late Devonian time period. With a name like Tetraxylopteris it’s going to be a challenge to write about this plant, but we are pros; let’s give it a try and even attempt to explain why this is something important in our region’s fossil record.

Take a look at our photo. It was taken in the open shed outside of the Gilboa Museum. The fossil lies upon the surface of an enormous boulder, collected in the Gilboa vicinity. Being outside, you can visit it any time you wish, all year round. The plant is a very distinctive one. You can see a main stem and then branches that stick out at nearly right angles. When those branches, themselves, have their own branches, those stick out–again at 90 degree angles. This rectangularity makes the plant so easy to identify. You just became an expert, but why is it important?

Tetraxylopteris takes us back to the Devonian time period when land plants had only recently evolved and were spreading out across the landscapes of the world. This was important evolution. We are speaking of the first time appearance of forest ecology itself–now that’s important.

The plant was a true land dweller; it had tissue that served to draw water out of the ground and pass it upwards into the stem and branches. We call that vascular tissue and it has always been an important feature of all true land plants. It had a woody stem and wood was a new “idea” for plants back then. Some of the very best preserved specimens have flattened structures on their outermost branches. These are thought to be proto-leaves, not true leaves but something broad, flat and photosynthetic. It was a good evolutionary start for real leaves.

It’s that woody stem that has been regarded as a trait that links it with the gymnosperms, many of which are today’s evergreens and cone-bearing trees. Tetraxylopteris was something you might call a bush; it probably did not grow as tall as a true tree. Some paleobotanists think it grew in thickets with each bush supporting its neighbors.

It was a primitive land plant in the manner of its reproduction. It did not produce seeds; it had an organ that produced tiny reproductive structures called spores. Individual spores are single cells that spore-producing plants use. They are caught up by wind and blown around, a lot like pollen. When they fall to ground they act like seeds and grow into a new plant. That may link this plant with ferns. Ferns, too, are primitive land plants that reproduce by using spores. If you think that the pollen season is bad nowadays, it might well have been much worse during the Devonian!

By the way, that name is not as hard to say as you might think. Try saying “tetra – xi – lopp – teris.” With a little practice it rolls off the tongue. And you will feel so smart just being able to say it!

The Gilboa Museum is having a big event, the Gilboa Fest, this Sunday, July 8^th from 10:00 to 4:00. Why not come along and see their fossil plants, including Tetraxylopteris, at the same time?

Contact the authors at randjtitus@prodigy.net, Join their facebook page “The Catskill Geologist.”