A summary of observations made by participants during BRDC’s “Discovering Diversity” program in a complex forest at the intersection of Big Branch and Big Laurel Creek, Konnarock, Virginia.
The participants focused on a small piece of land comprised mostly of forest. This forest and the forests nearby at similar elevations are quite unique when compared to the typical Virginia forest type (Oak-Hickory dominated). At this site we found a biological community that contains a diverse array of dominant trees including linden, buckeye, magnolia, and yellow birch.
The program was divided into two groups, and the groups were rotated half way through the program. One group focused on terrestrial forest life and another group focused on aquatic life in Big Branch (a stream along the eastern edge of the study area). The overall study area was about 150’ x 250’ in size (see map).
Elevation: low point, 3050’; high point: 3080’
Slope: gentle, lower slope semi-riparian
Rock Formations: Konnarock Formation, Mount Rogers Formation
Age: 760-730 million years old
Sedimentary Breccia: A breccia (coarse-grained rock that is made up of angular broken pieces of rock that are held together by a cement of minerals) that is formed by the consolidation of loose silt, sand, pebbles or other sediment.
Rhyolite: A rock that formed as the result of cooling lava. It contains the same minerals as granite, but is more fine-grained. One may observe bands of gray and pink in this rock.
Description of the rock:
There were two primary rock types on site:
Konnarock Formation; Maroon diamictite, rhythmite, and arkose. These are rocks that were deposited in habitats that included deep icy lakes and glacial activity. They are the silicified (fancy word for 'turned into rock') remains of muds, silts, pebbles and cobbles carried by glaciers. Interestingly, the stones seen in the silicified mud were dropped into that muck and consist of materials from formations nearby...ryholite, greenstone, and granite. This makes sense because the glaciers would have been eroding these materials from the land during that time...and, it was a landscape devoid of plants and animals!...mountains and valleys of pure rock, silt, and sand!
Mount Rogers Formation; Phenocryst-poor rhyolite. These rocks are a dark purple, and are the results of lava flows! Mount Rogers, White Top, and Pond Mtn. (NC) form the core of what was a massive and explosive volcanic complex. These once towering volcanoes have seen a lot of erosion, and have even found themselves buried beneath miles of sediment at different points in the geologic past. But today, we are afforded a view of these ancient volcanoes. It is worth noting here that this rock known as "Rhyolite" is high in silica, and breaks kind of like glass (concoidal fracture). This made it a choice material for use in making spears, knives, and other tools during prehistoric times. Somewhere on these mountains hides ancient quarries used by Native Americans!
Trees and Shrubs
1. black birch, Betula lenta
2. yellow birch, Betula alleghaniensis
3. northern red oak, Quercus rubra
4. red maple, Acer rubrum
5. sugar maple, Acer sacharrum
6. shagbark hickory, Carya ovata
7. yellow buckeye, Aesculus flava
8. white oak, Quercus alba
9. eastern hemlock, Tsuga canadensis
10. cucumber magnolia, Magnolia acuminata
11. American beech, Fagus grandifolia
12. Mountain Basswood, Tilia americana var. heterophylla
13. striped maple, Acer pensylvanicum
14. green ash, Fraxinus pennsylvanica
15. American witchhazel, Hamamelis virginiana
16. rhododendron, Rhododendron sp.
17. yellow poplar, Liriodendron tulipifera
1. Christmas fern, Polystichum acrostichoides
2. eastern hayscented fern (fiddleheads), Dennstaedtia punctilobula
Mosses, Bryophytes and Lichens
1. Unidentified lichen sp. (photo)
2. Unidentified moss sp. (by the stream)
3. Club moss species, unidentified
1. foam flower, Tiarella cordifolia
2. white violet, Viola sp.
3. may apple (blooming in field, but not forest), Podophyllum peltatum
4. partridgeberry, Mitchella repens
5. jack-in-the-pulpit, Arisaema triphyllum
6. star chickweed, Stellaria pubera
7. wild strawberry, Fragaria virginiana
8. white clover, Trifolium sp.
9. A small woodland phlox, Phlox sp.
1. poison ivy, Toxicodendron radicans
2. stinging nettle, Urtica sp.
3. Blackberry, Rubus sp.
1. common buckeye butterfly, Junonia coenia
2. black swallowtail butterfly, Papilio polyxenes
3. bumble bee, Bombus sp.
4. Multicolored Asian Lady Beetle, Harmonia axyridis
5. Multicolored Asian Lady Beetle, Harmonia axyridis ; hatching larvae, on the underside of a cucumber magnolia leaf
6. Soil Centipedes (Order: Geophilomorpha)
7. Ant (unidentified)
8. terrestrial snail, under logs (Group: Pulmonata)
9. large slug (Class: Gastropoda)
10. Millipede (Class: Diplopoda)
11. Earthworm sp.
1. Clubtail dragonfly (Gomphidae family)
2. Dragonfly species (unidentified)
3. Water bug (unidentified)
4. Crayfish species (Astacoidea fam.)
5. Snail species (Class: Gastropoda)
6. Mayfly adults (Order Ephemeroptera)
7. Mayfly larvae (Order Ephemeroptera)
8. Cranefly larvae (Family Tipulidae)
9. Caddisfly larvae with a case of pebble and sticks (Order: Trichoptera)
10. Caddisfly larvae with a case of leaves and sticks (Order: Trichoptera)
11. Midge larvae (Order: Diptera)
12. Stonefly #1, roach-like (Order: Plecoptera)
13. Stonefly #2 (Order: Plecoptera)
1. Wolf spider juveniles (Family: Lycosidae)
2. Daddy long-legs, or harvestman (Order: Opiliones)
1. devil’s urn, Urnula craterium
1. American Toad, Anaxyrus americanus (in the forest)
2. Blue Ridge two-lined salamander , Eurycea wilderae (terrestrial, under logs)
3. Dusky salamander, Desmognathus sp. (in the stream)
4. Black-bellied salamander, Desmognathus quadramaculatus (in the stream)
1. American goldfinch, Carduelis tristis
2. common raven, Corvus corax
3. American crow, Corvus brachyrhynchos
1. eastern cottontail rabbit, Sylvilagus floridanus, (scat
2. white-tailed deer, Odocoileus virginianus (scat evidence)
3. unidentified Canidae mammal (likely stray domestic dog or coyote) (scat evidence)
4. human, Homo sapiens sapiens (helicopter driver, program participants)
A Common Rarity, and the Helicopter
While the woodland and stream investigations produced many magical moments of discovery, none were as exciting as the arrival of a mammal and its flying machine. After the program guides and participants gathered along the edge of the woods at one end of a large field of Fraser fir Christmas trees. This tree, a species that is quite rare to find growing in the wild, litters the agricultural fields and hills of the highlands. From the large “Christmas tree” field from which we launched our woodland exploration one can see the Fraser fir’s wild and native habitat. Mount Rogers rises in the east, and its top is crowned by a wild Fraser fir forest.
If the native Frasers standing high upon Mount Rogers had eyes, they likely would have seen the helicopter approaching their brothers and sisters planted in rows in the fields below (Christmas trees to-be). They would have seen it heading toward an unsuspecting group of humans gathered at the edge of one of those fields.
As we stood there at “basecamp”, gathering notes, taking photographs, and compiling sketches, the thunderous beat of a helicopter suddenly entered our ears. Looking up, it approached from the woodland side, and it was upon us in an instant. The chopper had a large container suspended beneath it and before we had a chance to flee, the container opened and dropped its giant load of pellets. “Run!” We dropped everything and ran toward the community center, fearing the worst. We found out several days after the event (after tracking down the helicopter’s aviation company) that the substance dropped was a relatively harmless fertilizer (Di-Ammonium Phosphate 18-46-0). That was great news!
While I gathered notes for this booklet I reflected back upon that incident and view it as such an amazing turn of events. At the onset of the outing our biggest worries were blackberry thorns, poison ivy and stinging nettle. Then, along comes human and a flying machine…our senses were instantly recalibrated. The most interesting and memorable part of the outing was undoubtedly this large mammal, and its flying contraption. As the helicopter dropped its rain of phosphorous to a leached landscape, as we ran, the complex story of the Fraser fir raced through my mind. Humans (mammals) are an integral part of nature. I do hope that humans continue to grow in the direction of valuing exploration, discovery, and sharing knowledge. The resulting understanding and wisdom can help to improve the well-being of generations to come and they can inspire all of us to love and care for the places we live.
The Fraser Fir Tree: some amazing facts
- The Fraser fir forest on top of Mount Rogers is the northernmost wild community of this tree and it is the only “natural” stand in Virginia.
- The habitat of the Fraser fir, known as the Southern Appalachian spruce-fir forest, is the second-most endangered ecosystem in the United States.
- The Fraser fir-red spruce forest is a relic of the last ice age, meaning that in previous (and much cooler) climates it had a broader range in Eastern North America than today.
- A non-native insect called the Balsam woolly adelgid (Adelges piceae) was introduced to the United States in about 1900, and it has led to a dramatic decline of the Fraser fir. More than 80% of wild growing Fraser fir trees have been killed .
- There’s a really amazing set of plants and animals that live in the native stands of Fraser fir at Mount Rogers, such as the endangered Spruce-fir moss spider(Microhexura montivaga) and the Pygmy Salamander(Desmognathus wrighti).
- Virginia Division of Mineral Resources, 1993, Geologic Map of Virginia
- United States Geologic Survey website: http://minerals.usgs.gov/
- Google Earth, and map layer files available at USGS.