Hike to the Swamp

The 235 acres of Heldeberg Workshop land contains many different habitats. One of the most unique and ecologically valuable areas is the 67 acres of wetlands located north of the main entrance on Picard Road. It is part of a larger wetland referred to on some maps as Vly Swamp.

Fun fact: While you might think that Vly Swamp was named for someone with the surname “Vly,” vly is actually the Dutch word for swamp!

The map below illustrates more clearly where our wetland is located. Can you find Picard Rd and Tygert Rd on this map? About 41 acres of our wetland is located west of Tygert Road, marked “A” on this map, and 26 acres lies east of Tygert Road, marked “B”. A culvert exists under the south side of Tygert Road to help control flooding.

Map of portion of Heldeberg Workshop swamp. Adapted from New York State GIS Clearing House.

Today we will hike to the west side of Vly Swamp that is
marked “A” on this map.

Before we start out, let’s talk about what a wetland is. From the name “wet-land” you can probably guess that it refers to a place where the land is wet for much of the year. Wetlands vary in the amount and the chemistry of water that are present, as well as the types of plants, animals and soils that are found there.

Some people used to think that wetlands were “waste lands” and destroyed a lot of them by draining them or filling them in. That was a big mistake because wetlands are not only beautiful but have a very important function in nature. They help to control flooding, they clean pollutants from water, and they are home to lots of plants and wildlife like fish, frogs, salamanders, turtles, alligators, shrimp. No, we do not have alligators at Heldeberg Workshop, but we do have lots of other really interesting wildlife!

Who better to teach us about the importance of wetlands than Bill Nye, the Science Guy! Click here and listen to his fun video and learn why he thinks that wetlands are fabulous! We hope you will think so too, by the end of this hike.

Check what you learned by taking this pop quiz. Question: Wetlands are good for what?

a) They control flooding.
b) They clean pollutants from water.
c) They provide homes for wildlife.
d) They are a place to throw old tires.

If you answered a, b and c, you are correct! We should preserve wetlands because they serve a very important role in nature.

But where does the water in Vly Swamp come from? The answer to that question is in the cliffs of the escarpment behind us. If you hiked the trails at the base of the escarpment in the summer, you probably crossed several stream beds, some dry and some wet depending on the weather. In early spring, though, these stream beds gush with water. And most of the water in those streams was once snow in the land above us! As the air temperature gets warmer, the snow melts and water cascades down over the rocks of the escarpment and fills the stream beds.

But the water in the stream beds is not pure H20! That water washes over the rocks of the escarpment. Some of these rocks are rich in minerals like calcium carbonate and those minerals are carried along with the snow melt. That cold water percolates down into the soil and continues to flow in underground springs that emerge on the north side of Picard Road as the seeps in Vly Swamp.

Now let’s dig a little deeper. The NYS Heritage Program further classifies Vly Swamp as a rare kind of wetland called a “Marl Fen.” What does that mean?

To answer that question, break the name “Marl Fen” into two parts. Fens are shallow wetlands with very cold water. They are fed primarily from water trickling up from the ground, rather than from water that washes in from the surface. That is certainly the case with our Vly Swamp. Its water is icy cold and bubbles up from below. Click here to see a short video showing some of these seeps.

On a recent summer hike to the swamp we measured the water temperature at a seep at 44, slightly warmer than a refrigerator! Brrr. Now it seems cold, but in winter the water can be warmer than the air and will “steam.”

So, our swamp is certainly a fen. But what about the word “marl.” What does that mean? The word “marl” is derived from a Middle English word, marle, that means “soft rock.” In modern usage, it describes a white, granular substrate, made of limestone. Below is a picture of some white marl surrounding a seep in our swamp.

But what is marl made of, and where does it come from? The answers to these questions lie in the cliffs of the escarpment. Remember, the snowmelt that is the main source of water in Vly Swamp rushes over and through the sedimentary rocks. Some of these rocks are limestone formed from the shells of some fossils like corals and mollusks. Limestone is rich in different crystal forms of calcium carbonate (CaCO3).

As result of the photosynthetic action of algae like Chara, as well as chemical processes, the level of carbon dioxide in the water is low. Under those conditions, calcium settles out of the water as solid calcium carbonate (CaCO3). Over time, this calcium carbonate accumulates on the swamp floor and forms the gritty, white-colored sediment called “marl.” There is so much marl in some places in Vly Swamp that little marl islands are formed!

And all that marl alters the pH of the water. While most swamps are acidic, the water in a Marl Fen has a neutral or basic pH, i.e. a pH of 7 or greater. This restricts the growth of most aquatic plants so the water in a Marl Fen is very clear, as well as being very cold. But while some plants don’t like this environment, other plants love it! Maybe that’s why a Marl Fen has some unique plants and animals.

I think you’ll agree that Vly Swamp really is a Marl Fen, a rare kind of wetland! DEC rates the shallow, cold, clear water of Vly Swamp as one of the top three wetlands in all of New York State for amphibian diversity! Twenty species of salamanders and frogs have been found here!

We are lucky to have such a unique ecosystem in our own backyard!
Check what you have learned by taking this pop quiz.

Question: What are characteristics of a marl fen?

a) They have a neutral or basic pH.
b) They have very cold water.
c) The water bubbles up from the ground.
d) They are shallow.
e) They are a place to throw old tires.

If you answered a, b, c, and d, you are correct! We should preserve Marl Fens because they serve a very important role in nature.

Our hike begins near the Archery Area of the Heldeberg Workshop property. Walk northward on the access road toward Picard Road. You will see a stone wall on your right. Look for an opening in the stone wall, marked by an arrow on the picture below, and a sign on a tree directing you to the Swamp Trail.

Opening in the rock wall

This path is marked by colored trail markers, so keep your eyes peeled for these markers and you won’t get lost. You will walk diagonally along this trail to Picard Road.

This short stretch of our hike takes us through a beautiful stand of stately trees. Try to use all your senses to discover what you can see, hear and smell. You will pass some large Sugar Maples (Acer saccharum). Sugar Maples produce a sweet sap that can be tapped and concentrated to make maple syrup. Maple syrup was first made by Native Americans. Think about this the next time you eat pancakes!

Pictured below is a tall deciduous Sugar Maple in the foreground with many evergreen hemlocks behind it.

Let’s zoom in on a Sugar Maple leaf so you can see it better. There is a deep U-shaped notch between the 5 pointy lobes of the leaf. Look at where the arrow is pointing in the picture below. Doesn’t that notch look like the letter “U”?

The predominant tree in this part of the Workshop is Eastern Hemlock (Tsuga canadensis), a coniferous (evergreen) tree that is native to eastern North America. It is a long-lived tree that can reach heights of up to 175 feet. If you look to the east, you will see many of these beautiful trees.

You will also see smaller hemlocks down in the swamp as well as along stream beds up along the escarpment as it can tolerate wet soil.

Hemlocks are high in tannic acid. Their bark was used in the past by the tanning industry to tan, or preserve, animal hides. Water near Hemlock trees may look foamy and brownish in color due to tannic acids. Sadly, while hemlocks can live over 500 years, they are currently threatened by an alien invasive aphid-like insect called the Hemlock Wooly Adelgid – HWA – (Adelges tsugae).

Fun fact: While it is easy to see the large trees that are all around us, the roots of trees interact with the organisms found in the soil itself. Healthy soil is rich in thread-like fungi that attach to plant roots and increase their ability to absorb water. These fungi are sometimes referred to as mycorrhizae. Look at the picture of the two plants below. The plant root on the right has no mycorrhizae while the plant root on the left has many fungal mycorrhizae.

Which plant, A or B, do you think will be able to absorb more water and soil nutrients? If you said “A you are correct! And the mycorrhizae benefit from this partnership as well. They get nutrients from the plant to help it grow. There is a lot more going on in soil than first meets the eye. This is pretty amazing, don’t you think?

Further along the path, we turn over some leaf litter in search of salamanders, amphibians with smooth, moist skin. To our surprise and delight, we spy one wiggling in the duff. It is the Eastern Red-Backed salamander (Plethodon cinereus). These woodland lungless salamanders live in damp and moist habitats and exchange oxygen through their skin and tongue. It is incredible to think that they can survive up to 25 years!

Below is a picture of the dark Red-Backed Salamander.

The upper body of Red-backed salamanders can exist in one of two color morphs, lead-back or red-back. Lead- back morphs are grey to black in color. Red-back morphs have an orange to red stripe down its body and tail.

With a little more hunting we find the red-back morph and take a picture of these two morphs side by side. Can you tell which color morph is which in the picture below?

Fun fact: If attacked, Red-Backed salamanders can lose all or part of their tails and so evade predators! Then a new tail grows.

While we could spend more time in this forested area, we need to head down to the swamp. Look for a sign along the south side of Picard Road pointing to the swamp.

Carefully cross the road, then walk about 50 feet to your right. You will soon see another sign pointing you to a trail that runs parallel to Picard Road, before dropping down to our swamp.

Watch out for Poison Ivy (Rhus radicans) along this open section of the trail. Remember the saying, “Leaflets of three, let it be!” It has an oil, urushiol, that some people are allergic to. If you are, contact with Poison Ivy can give a very nasty, itchy rash. Look at this picture of Poison Ivy to remind yourself of what it looks like.

A little further along the trail we see a cluster of plants with large, deeply veined leaves with a notch at the base. It is one of the first plants to bloom in early spring. It is Eastern Skunk Cabbage (Symplocarpus foetidus), a plant that likes wetlands and moist slopes.

This time of year, only its leaves are visible but in late winter and early spring it produces a red spathe that looks like rotten meat. A spathe is a hooded structure that contains flowers.

With a name like “Skunk Cabbage” you can probably guess that this plant does not smell very nice. Its leaves and spathe can emit a smell that is a lot like the odor of a skunk! But that odor is important because it attracts the flies and carrion beetles that pollinate the flowers inside it. Skunk Cabbage has an enormous root system that helps to stabilize banks around streams. Click here to watch a short video showing what Skunk Cabbage looks like in early spring.

As we walk along the moist, shady trail, we start to see more and more ferns, ancient plants that were common when the dinosaurs roamed the Earth! Ferns are a kind of bridge between more ancient plants like mosses, which lack a vascular system, and more recently evolved plants which produce flowers and seeds. Vascular tissue manifests itself as the veins that transport water and other nutrients in the plant. All the plants we talked about so far today are vascular plants. While ferns do not produce flowers and seeds, they do contain a vascular system.

Below is a picture of Christmas Fern (Polystichum acrostichoides), an evergreen fern native to eastern North America that is sometimes used in Christmas decorations.

If we turn the frond on its side, zoom in and use our imagination, you may be able to see a row of stockings hanging there. You should also be able to see the distinctive vein in the middle of each leaflet.

Nearby, we spy a group of unusual white plants, each about 4” tall, that are sometimes mistaken for mushrooms. It is Indian Pipe (Monotropa uniflora), also known as Corpse Plant because of its ghostly white color. It is a small plant, so you need to look closely to find it. Use your imagination to turn the four plants in the picture below 90◦ to the right. Doesn’t it look like a little white pipe? The bowl of that pipe, though, is its bloom which produces pollen, nectar and seeds.

Indian Pipe is a sort of ecological wonder because it lacks chlorophyll. That is why it is not green. So how does it get nutrients?

The answer to that question is in the soil! The soil along the trail is teeming with filamentous fungi. Remember, these fungi grow into a vast network of threads, also known as mycorrhizae, that connect many other organisms to it. Mycorrhizae, for example, attach to the roots of trees where they increase the ability of tree roots to absorb water. As a payback, the mycorrhizae receive some nutrients from the trees. It is a kind of “win-win” situation since both organisms benefit from this arrangement.

But what does this have to do with Indian Pipe? A lot, as we will soon learn. Since Indian Pipe cannot make its own food, it must get its nutrients in some other way. It may sound weird, but that other food source is the trees around it!

But how does this little white plant do that? By being a freeloader, that’s how! Indian Pipe roots connect to the fungal mycorrhizae that are joined to tree roots. The mycorrhizae then pass some tree nutrients back to the Indian Pipe plant.

Pretty ingenious but weird, don’t you think? Indian Pipe takes nutrients but does not give the mycorrhizae or trees anything in return. This parasitic plant is so unusual that it is placed in its own family by botanists. It is not a complete freeloader though. Bees and ants enjoy its sweet nectar, so it plays a role in food webs.

While we will pass many other interesting plants along the trail, we need to get to the open water of the Marl Fen, and it is just ahead of us. I hope you are wearing your rain boots, otherwise your feet may get wet!

This is a picture of what it looks like.

You will notice that the water is shallow here. Look for seeps coming up from the ground. Touch it to test the water temperature. It is very cold. If you brought pH paper with you, you can check its pH as well.

There are many shrubs and small trees here in our Marl Fen, and we’ll talk about a few of them. Eastern Hemlocks are present, but they are smaller than the specimens we saw in the woodlot across the road.

A characteristic swamp tree is Speckled Alder (Alnus incana). It is native to wet soils of northeastern North America and can form dense thickets that are difficult to get through. The foreground of the picture below contains a Speckled Alder.

Another small, solitary tree characteristic to Marl Fens is Poison Sumac (Toxicodendron vernix). It is a cousin to Poison Ivy. Like Poison Ivy, it produces the oil urushiol that can give you a painful, itchy rash. Make sure you can identify it, and do not touch any part of the plant. The tree is solitary with a gray bark. It produces pinnately compound leaves. Each leaf has red stems and 7 to 13 leaflets. How many leaflets are in the specimen pictured below? Leaflets have smooth edges that are pointed at the tip. They are shaped like a bird’s feather. I see 9 leaflets, do you?

Poison Sumac produces green berries in the spring that stay green for most of the summer. The picture below was taken in August and the berries are still green. Can you see them? Like Poison Ivy, mature Poison Sumac berries will turn whitish in the fall.

Poison Sumac is not a common plant. Our Marl Fen is one of the few places where it is found in Albany County.

Now let’s explore what is in the water of our Marl Fen.

A plentiful organism, about 6” long, at the edge of the water is the algal organism: Chara sp. While Chara may look like a plant, they are classified as algae because they lack true tissues. Chara prefer cold, fresh water, that is rich in limestone, so the Marl Fen is perfect for them.

Chara are covered with calcium carbonate deposits that make them rough and stiff to the touch. Because of this, they are often referred to as stoneworts, a word that means “stony plant.” This is what one individual specimen looks like:

Further out in warmer, shady water we use our nets to scoop up small crustaceans (0.1 inches) called scuds, side-swimmers or freshwater shrimp.

Scuds look like a miniature shrimp with a body that is flattened sideways. It is categorized with the Amphipoda, a group that contains thousands of different species, because it has two types of legs.

Like shrimp, scuds have a hard exoskeleton. They have a comma shaped body with many pairs of legs. Their distinguishing feature is that they are flattened sideways like a flea. Below is a diagram of a scud.

Diagram of a scud. Image courtesy of Wikipedia.https://en.wikipedia.org/wiki/Amphipoda

Females have a pouch for the young. The male hitches a ride on the female until she deposits her eggs in a pouch where he fertilizes them. The young hatch and stay in the pouch (you can see them squirming around under a microscope). When she sheds her exoskeleton like all crustaceans, she sheds shell and babies into the water.

Scuds eat microscopic plants, animals, and debris found on plant leaves. They help to keep the water clean. They can be eaten, in turn, by larger insects and salamanders.

Wriggling in the water we see a tiny reddish-brown aquatic insect, about 0.5” long, that can eat scuds and be eaten, in turn, by salamanders.

It has a head with 2 large antennae, 6 legs and a segmented abdomen with 2 prominent tail-like structures. It is a Stonefly (Plecoptera sp) larva. We have enlarged a picture of this Stonefly so you can see it better.

But where are the salamanders?

We lift a flat rock, wait until the water clears from the upwelling seep, and find a tan-colored larval Spring Salamander (Gyrinophilus porphyriticus) with a thick, keeled tail and a flat nose. They have a light-colored line that runs from the eye to the nostril, but it is not always conspicuous. Can you see it in the picture below? The coloration of Spring Salamanders can vary from salmon or light brown to pink or reddish. They need this cold spring and will not survive in warm water. They eat earthworms, insects like stoneflies, and even other salamanders.

A smaller salamander that Spring Salamanders do eat is the Two-lined Salamander (Eurycea bislineata). With a little hunting, we find one! It is smaller and thinner than a Spring Salamander with a long tail. It is a yellowish- tan color with two dark lines on each side of its slender body that make it easy to recognize.

While there is still much to see in the Marl Fen, we need to get back. Follow the trail markers. You will climb up a fairly steep slope and come out on Picard Rd. Across the road you will see the main entrance to Heldeberg Workshop.

Before we end our virtual hike, we’d like to share a part of our wetland with you that is off of Tygert road. Join us for this short imaginary walk. Below is a picture of what that part of the wetland looks like. The water is deeper here and is lined with Narrowleaf Cattails (Typha angustifolia) and Phragmites (Phragmites australis) two non-native plants which can be invasive.

There is a very interesting small yellow plant floating in the water. It is Common Bladderwort (Utricularia macrorhiza). If you look closely you may see it in the middle of the picture above. Below is an enlarged image of this plant.

The flower is yellow and contains two petals. But what is really remarkable about this little plant is that it is carnivorous! Its underwater stems have small “bladders” that can “vacuum” up small aquatic organisms like mosquito larva! Bacteria inside these traps digest the prey which is then taken up by the plant.

But we can’t leave our wetland without pointing out what is currently happening there. We told you at the beginning of our walk that wetlands can be destroyed by draining or filling them in. But the North American Beaver (Castor canadensis) can alter a wetland as well. Below is a picture of a large tree on the side of Tygert Road that was recently cut down by beavers!

Beavers use the branches of trees to construct an underground lodge and to dam the water. Our wetland may soon have deeper water that will not be able to support typical Marl Fen species.

How do you feel about that? It is complicated. What is good for beavers, may not be good for other organisms that require cold, shallow water with a lot of oxygen.

We hope you enjoyed your hike to the Marl Fen, and
agree with Bill Nye’s claim that wetlands are fabulous!


The Heldeberg Workshop is registered with the IRS as a charitable organization under section 501(c)(3) and therefore can receive tax-deductible donations.

Thank you