Piece-by-Piece--Hiking Knoxville's Urban Wilderness Trail

Piece-by-Piece is the name of a series of hikes scheduled monthly by Ijams Nature Center, and led by naturalist, Stephen Lyn Bales.  These hikes will traverse the South Loop of Knoxville's Urban Wilderness Trail in 2-3 mile sections.  

Saturday, Feb 8th included the Ross Marble Quarry Natural Area, an area of natural limestone deposits, quarried by the Ross Marble Company beginning in 1881.  The area is an interesting combination of large quarried limestone block, some stacked into towering walls, and nature's gradual reclaiming of the area.  The marble produced here was not true marble but a crystalline limestone that polished easily and had an attractive pinkish-gray appearance.  It became known as Tennessee Marble and has been highly favored for use in buildings and monuments in Tennessee, New York and Washington. DC.

Above, an area of slag deposits, the "ashes" created from a lime kiln used to convert broken chunks of limestone into agricultural lime powder.  As the slag area is reclaimed by nature, it supports cedars that favor its alkaline quality.  

As we reached the trail end in the Hayworth Hollow area, we were surrounded by towering stacks of limestone rock.  Large chunks of limestone that were not used for marble were stacked into these enormous walls. The reddish coloration seen in some of the blocks is caused by iron oxide which leaves a rust-like stain.

A system of caves runs under the limestone deposits in this area and provides habitat for the endangered Berry Cave Salamander (Gyrinophylus gulolineatus).  Several species of bats are also known to roost in these caves which are gated to protect wildlife.

Lyn, a master naturalist, turned over some leaves in the pond to demonstrate how you can generally find salamanders and recognize salamander eggs during breeding season.  A talented story teller and author of two books and numerous articles, he shared some tales of frogs and salamanders from his years growing up in the Smoky Mountains.

Further down the trail we explored the Keyhole "wall" at the Ross Marble Quarry, below.  At the top of the wall you can see railing that was installed to offer a safe crossing as you continue on the trail. 

The limestone desposits that included the prized industrial grade limestone sold as Tennessee marble in the area are part of the underlying Holston Formation that passes through the 300-acre Ijams property.  

You can walk through the keyhole to explore the other side.  The images immediately above and below were taken at a different time of year and show the proportional size of the keyhole feature.

On our return to the trail head, we hiked along the ridge with a distant view of the Smokies on one side and blocks of limestone on the other.  

Links and Resources:

Tennessee Marble
Ijams Nature Center
Stephen Lyn Bales--Nature Calling
Marble Quarry Map
Piece-by-Piece--Urban Wilderness South Loop
Knoxville's Urban Wilderness
Legacy Parks Foundation--Knoxville's Urban Wilderness hike descriptions with trail maps
More about geological features of the area:  Ottosee shale to Lenoir limestone

Pileated Woodpeckers in the Snow

Pileated woodpeckers are delightful birds to watch and it is an extraordinary experience to observe one at eye-level and have it linger for a while.

On January 28th, during a beautiful snow fall, I first heard, then located, two pileated woodpeckers foraging around the yard, visiting old growth trees both in the yard and its wooded edges.  It was 19 degrees F, COLD and windy.  

Above, you see the female (top) and the male below her after she briefly landed on the same tree and they foraged together for a few minutes.  Below, the male as he looks up from foraging.  This bird's woodpecker movements are jerky, alert, ever scanning the environment and checking movement above and below, even though they sometimes ignore humans.  Among their predators are Cooper's Hawks and the Great-horned owl.

I finally retreated inside because I was so cold and my view was obscured by other trunks and limbs. Within 30 minutes, as I stood looking out the window at the snow and feeder birds, I saw the female as she landed on a tree at the edge of the patio.  This is the sort of opportunity that calls for grabbing a coat and camera and maneuvering out the door as carefully as possible.

Above is a photo of her farther out in the yard.  Notice how she has her tummy feathers fluffed with air protecting her legs from the cold and adding to her overall warmth.  She has a very young face and I suspect that she is the male's offspring rather than his mate.  I have seen this family together in April in seasons past as they begin their breeding season.

I opened the door and was very surprised that she ignored me and continued with her foraging.  Clearly she was finding something of interest. I was torn between zooming to get close images, or pulling back to get her whole body in.  I adore seeing the expression on her face, but also like the image below that shows that long sturdy tail-brace, so important in her movement and balance.

Below you can see her tongue as she probes under the bark. Woodpeckers have sticky, barbed tongues that help retrieve the insects that are hidden in crevices and underneath the bark.

Communication among family members is as facinating as watching these woodpeckers scoot up a tree, as they periodically stop to probe, pound, and extract insects.  The bugle-like call can be heard on the Cornell All About Birds site (link below) and is their most famous and loudest call.

There are also more intimate calls that specifically occur when family members are together, most often attributed to mates, but also heard when juveniles are foraging with parents.  On this occasion, I only heard the bugle call and occasionally the "kuk-kuk-kuk" sequence.

The habitat here is old growth forest with decaying trees in a suburban area where home development is interrupted by undeveloped wooded slopes.  These are the kind of broken zones that support many woodpecker species and allow people and wildlife to peacefully co-exist together.

The winter months are exceptional woodpecker-viewing months in east Tennessee.  Woodpeckers are easily spotted on bare trunks and tree limbs.  They are busy foraging to keep warm and sustain their nutritional needs.  Some woodpeckers from the mountains come down to the Tennessee Valley to spend the winter, among them the yellow-bellied sapsucker.

Above, a male yellow-bellied sapsucker forages in the yard at the same time the pileated family was present. Below, the male pileated woodpecker among large decaying limbs.

Images were taken with a Canon Rebel T2i with 100-400 Canon zoom lens.

Links and Resources:

More pileated woodpecker family posts on this blog.
Cornell All About Birds--Pileated Woodpecker.  Be sure to listen to the calls.
Cornell on Yellow-bellied Sapsucker.  Be sure to also listen to this sapsucker's call.  He blends with tree bark so well, that the call will likely be how you learn of his presence.