In today’s edition of Charlie’s Picture of the Week, he talks about the wildlife and landscape of the Johnsonburg Swamp Nature Preserve.

How is this for a short introduction: “Johnsonburg Swamp Nature Preserve is one of the most species rich natural areas in New Jersey”? (The Nature Conservancy)

WHY IS THIS LAND SPECIAL?

Johnsonburg Swamp Preserve, established 1990, contains a limestone forest and is one of the most important and species-rich natural areas in the state. 

Mud Pond is a natural limestone wetland, which is home to rare plants, plus waterfowl and other animals. Limestone outcrops overlooking the pond include the largest limestone rock formations in New Jersey (shown in the main photo)! 

This limestone creates special calcium-rich soil for rare plants:

• hoary willow
• ebony sedge
• leathery grape fern
• white-grained mountain rice grass
• lesser bladderwort

The lesser bladderwort only grows in three other places in the state. It’s a carnivorous plant that floats in water. It has yellow flowers

Threatened wildlife that live around Mud Pond include Great Blue Herons, Red-headed Woodpeckers, Barred Owls, Red-shouldered Hawks, Wood Turtles and Longtail Salamanders. 

HOW WAS THE LIMESTONE CREATED:

The Preserve’s limestone and outcrops were formed millions of years ago, when this area was under the ocean.  As sea creatures like oysters, clams, mussels and coral died, their shells were broken down by waves and settled on the bottom of the sea.  They were compacted over millions of years creating limestone.

CREATION OF MUD POND – WHAT IS A LIME SINK:

At the center of Johnsonburg Swamp Preserve is Mud Pond, a highlight of the area’s karst landscape.  Karst refers to topography formed when waters erodes soluble rock like limestone.  Here is how the pond was formed: 

• First – years of rainfall, which is slightly acidic, slowly dissolve the calcium-based limestone bedrock.
• Second – overtime rainfall creates caverns.  Top soil deposits in caverns changes the shape of the landscape, ground begins to sink.
• Third – rainfall continues to dissolve bedrock causing caverns to expand into large cave like structures.  Sediment and topsoil continue to deposit into the caves and a large depression forms on the landscape.
• Fourth – soil and debris plug up entrances to the caverns.  Slow drainage of the topsoil allows wetlands and water features to form.  NOTE:  this process is illustrated in photos taken of the excellent signage provided by the Nature Conservancy in my Flickr site album.

My Two Visits:  A truly special and unique area.  This 714-acre preserve in Frelinghuysen Township celebrates and showcases many divergent physical features along with affording the visitor many opportunities to view the Wildlife and some rare fauna!  The scenic limestone outcrops called High Rocks, overlook Mud Pond to the west and north.  They are the largest rock formations of their kind in the State of New Jersey, and a signature feature of this landscape. 

I actually made two visits here last week, my first consisted of a hike along the trail that parallels Mud Pond. 

The first half of your journey is through the woods catching glimpses of the pond through the woods.  This first section of the trail is a pond level walk, it takes you to a shoreline outlook, which is one of the attached photos.  There you notice the limestone outcrops beginning to rise up along the pond.  If you look towards the ‘High Rocks’ at the end of the pond you can see the small bare outcrop or High Rocks which is your destination and also our Photo of the Week. 

From this outlook you need to backtrack a short distance and then follow the trail up along the ridge above the pond to High Rocks.  This is a nice visit, with a lot of chances to see wildlife.  I am going to focus on the Scarlet Tanager, my first trip I had three separate occasions to view them and then on my second trip with a different trail had another opportunity to see them.  I observed no less than six hawks, just couldn’t get a photo of same! 

My second visit was taking the Glenn Wyse Trail which begins a short distance from the main parking lot actually departing from the trail to the High Rocks.  This is a short .6 mile trail, but it really showcases the many, many small limestone outcrops amid the woods along the pond.  You are constantly going through, up and over these outcrops getting to three benches each giving views of the pond. 

I was going to recommend keeping your eyes to the ground to see some of the unique plant life in this area, BUT, then you would miss the birds and wildlife of the forest and pond!!  I am going to play it SAFE, just be observant!!  There is always something to see!!  As a matter of fact – there is always something to hear!!  These wetlands offer a constant chorus of sounds, to the point I made several videos, not for what you would see BUT FOR what you were hearing!!

NOTE:  when visiting my Flickr site please look and read the wonderful signage which I took photos of – it really explains just how special this site is.  I have labeled my photos of some of the special and unique plantlife!!  Also keep in mind, limestone is a major feature throughout Warren County and our region and there are other sites that also celebrate this interesting physical feature, one example being White Lake.

DIRECTIONS:  From center of Johnsonburg, go to CR 519 and make a left turn by ballfields, you are heading towards Rt 94, go through the tunnel under the RR and in about a half mile look on right side of road for a small sign Johnsonburg Swamp Preserve, looks like a driveway.  Go in about quarter mile to parking area.

Link to the Nature Conservancy’s Johnsonburg Swamp Preserve site

Please go to my Flickr site for more photos and information

Enjoy Your Open Space

Charlie Fineran

Charlie Fineran is Allamuchy’s Director of Open Space, Allamuchy Township Environmental Commission Chairman and Allamuchy Historical Society President.