From a geologic perspective, Brumley and Clinch Mountains that surround Hidden Valley, were formed during the Appalachian Orogeny, which occurred during the mid to late Paleozoic Era over 300 million years ago. This was a time when surface layers of the Earth’s crust, called plates, collided with tremendous force, overriding one another, folding, and faulting to create mountains. Rock from this period includes limestone, dolomite, sandstone, and shale. Thus, the Clinch Mountain chain, a natural geographic barrier that runs northeasterly from Tennessee into West Virginia, was formed. Fossilized flora and fauna, such as these Brachiopods that lay on the seabed about 350 million years ago, are found in rocks high on the mountains. Little Moccasin Gap, located immediately below Hidden Valley, is one of only two true gaps through Clinch Mountain.

After the last ice age, about 10,000 years ago, the area surrounding Hidden Valley was lushly vegetated. Forests of centuries old trees, hundreds of feet tall, with trunks so large it would take several men to stretch their arms around, dominated the landscape. A high elevation cranberry bog flourished where Hidden Valley Lake now glimmers. Bison, Elk, White-tailed Deer, Bear, Bobcat, Cougar, and many species of birds were on the mountain; Brumley Creek was full of native trout and the North Fork of the Holston River contained a large variety of fish as well as freshwater mussels.

The first people to arrive in the area surrounding Hidden Valley probably came down the Holston River or followed trails made by animal herds. The earliest known evidence of humans in far southwest Virginia are projectile points, such as these found in Hansonville at the base of Clinch Mountain, dating from the early archaic period between 8,000 and 10,000 years ago. It is not known who these people were, but Native Americans from time immemorial have considered this region as sacred hunting grounds and permanent settlement was forbidden. However, there is plenty of evidence of temporary hunting stations. One such station, dating at least as far back as the woodland period about 700 years ago, was in Hansonville. It was also a strategic location that controlled access and trade through Little Moccasin Gap.

Europeans began exploring and surveying far southwest Virginia in the late 1600s. Indian tribes encountered in those days included the Cherokee and Shawnee. Immigrants began settling the area surrounding Hansonville, Clinch and Brumley Mountains, during the 1740s. Troubles pioneers had with the Indians resulted from building permanent settlements in sacred hunting areas where it was forbidden and along trails used for centuries for trading and warfare. Daniel Boone and his family traveled through Little Moccasin Gap and resided at Moore’s Fort in nearby Castlewood from 1773 through 1775. By the summer of 1774 Indian hostilities increased. CPT William Russell, who settled in Castlewood in 1770, was placed in command of both Moore’s Fort and Fort Blackmoore, and ordered to “collect all the settlers in the Clinch Valley into the forts”. In early July 1776, John Douglas, who served as a Sgt in the militia under CPT William Cocke in August 1774, was shot and killed by Indians in Little Moccasin Gap, just south of where Hidden Valley Road turns off from US 19 North, while returning to Clinch after visiting friends and relatives in Holston. The DAR erected a plaque at the site and a rest stop was established known as John Douglas Wayside. By the late 1800s many immigrants were traveling through Little Moccasin Gap and settling in the surrounding area. During this time John Hanson built and successfully operated a store at the northern mouth of Little Moccasin Gap, close to where the Indian’s had established a temporary hunting station centuries before.

At the turn of the 20th century the forests on Clinch and Brumley Mountains surrounding Hidden Valley were still virgin. The timber industry was booming by then and a small gauge railroad along Brumley Creek was built to haul out the logs. Oral histories claim a tree had to be at least four feet in diameter when chest high on a man to be logged out. Few trees of that size remain today. Later that size requirement was forsaken and most all of the trees on the mountain were harvested. So, the forest surrounding Hidden Valley today is secondary growth. Remnants of the old railroad can still be found along Brumley Creek below the dam of Hidden Valley Lake, as can unmarked timber trails and roads zigzagging across the mountain.

By 1963 the Virginia Department of Game and Inland Fisheries (DGIF) acquired Hidden Valley, upgraded the small dam, and created Hidden Valley Lake. During the spring of 1978 Appalachian Electric Power Company (AEP) targeted Hidden Valley and the community of Brumley Gap for the creation of what was intended to be the world’s largest pumped storage facility. At an estimated cost of $2 billion, the project plan was to dam Brumley Creek at the gap, flood the valley, pump the water up to Hidden Valley Lake, then release it back into the valley during peak demand, thus generating as much as 3,000 megawatts of electricity. A large container to house water monitoring equipment that was helicoptered in and assembled in pieces in a gorge along Brumley Creek about two miles below the dam can still be seen. Approximately 300 families would have been displaced by this project. A David and Goliath struggle ensued as the citizens of Brumley Gap fought AEP. Ultimately a series of delays caused AEP to cancel the project. In November 1988 Hidden Valley Lake was drained to repair the spillway below the dam and was refilled in July 1989. Over the years DGIF has routinely stocked Hidden Valley Lake with a variety of fish with varying degrees of success.

Anna:

While in Costa Rica, I became obsessed with old plants, specifically Podocarpus.  I spent days hunting through the cloud forest for a Podocarpus tree that my botanist friends promised me was present along a specific trail, but I never found so much as a needle.  To understand why the tree was so intriguing, we'll have to step back in time about 250 million years.

I've written before about plants that date back to Pangaea, when all of the present continents were lumped together into one land mass.  These ancient connections result in genera with widespread distributions, often found throughout tropical parts of the world (pantropical).  But I was just as interested in the next stage in earth's geologic history, when Pangaea split in half.

The northern half of Pangaea was known as Laurasia, a supercontinent that later broke further into North America, Europe and Asia.  Since these three continents remained stuck together for some time after Pangaea splintered, their plants and animals show striking similarities.  That's why when I reached England at the beginning of my year of travel, I was shocked to see nearly familiar oaks and maples around me.

Similarly, all of the continents currently in the southern hemisphere --- South America, Africa, Australia, and Antarctica --- were part of the southern supercontinent, Gondwana.  I had already explored one Gondwana continent in great depth, but Australia has been separated from the other continents for so long that many of the plants I saw there were endemic and grew nowhere else.  In particular, the ancient Antarctic flora was only barely visible in Australia since the continent had turned hot and dry, unlike the cool, temperate conditions that had once dominanted in the southern tip of Gondwana.  Costa Rica was my chance to fill in the gaps and see some Gondwana species, and Podocarpus was one of the most distinctive examples of the Antarctic flora.  I was also interested in finding Podocarpus since the tree is one of the few native conifers found in Costa Rica.  (A pine plantation can be seen by the side of the road, but pines are an import from the north.)

So I beat the bushes in search of a conifer --- surely a conifer wouldn't be that hard to find?  Finally, as my time in Costa Rica wound to an end, my botanist buddies took pity on me and joined me for a field foray, leading me straight to the Podocarpus...which looked nothing like the conifer I was expecting.  The leaves were long and broad, only barely pine-like and the tree itself had none of the regularity I expect from conifers.  Good thing I had botanists along on the hike!



3-21-01
We're supposed to go tomorrow at 4 to look at the house, but we left the reserve at noon and sought it out.  It's big and bare, but it's a house and is on the most lovely side road.  I decided that I'm going to call and see if we can move in tomorrow.  I've already started packing up our room, so we'd better get it.  I'm just terrified someone else will snap it up!


Maggie:

3-21-01
Today on the way home from the Preserve, we snooped around what we imagine is our house. It is a squarish yellow house on top of a hill with a woods but not too exciting architecture. We saw the kitchen and living room by peeking, but the curtains blocked us from the bedrooms. We are very eager and our belongings are all spread over the floor for packing.

Our guide at Uxmal threw so much information at us so quickly that I'm still digesting his words nearly a year later.  At one point, he stopped beside a hole in the ground and mentioned that the ancient Mayans got their drinking water from cenotes.  Then we barreled on to see the next ruined building, leaving me lagging to snap a quick photo.

The Yucatan is, in essence, one big slab of limestone underlain by an extensive cave system.  If you peer carefully at a map, you'll see that the peninsula seems to be devoid of creeks and rivers because all of the rainwater seeps quickly down into the caves beneath the surface.  Over time, cave roofs collapse and form sinkholes, just like in my familiar stomping grounds, but in the Yucatan there is so much groundwater that these holes are full of water --- cenotes.

The Yucatan is surrounded by ocean on three sides, and that saltwater seeps into the peninsula's cave system, saturating the lower levels of the groundwater.  Luckily for the ancient Mayans, though, rainwater is lighter than ocean water, so fresh water floats near the surface and provides a source of drinking water in an otherwise waterless area.  Cities --- notably Chitchen Itza --- were located near large cenotes, and "cenote" is merely a Spanish version of the Yucatec Mayan word for "well."

The Mayans considered cenotes sacred not only because they were sources of water, but also because each cenote was believed to be an entrance to the underworld.  Sacrificial pottery, animals, and even humans were tossed into the watery depths as offerings, and skeletons have been found at the bottom of many cenotes in the Yucatan.

As if the tantilizing geology and human history of cenotes weren't enough, a circle of these sinkholes on the northern coast of the Yucatan peninsula has an even more star-studded past.  The regularity of the circular shape tipped scientists to study the area in more depth, which led them to discover that the cenotes trace the outline of a meteor crater 110 miles in diameter.  The Chicxulub crater was dated to 65 million years ago --- the exact moment when dinosaurs became extinct.  Although scientists aren't sure whether a meteor was the sole cause of dinosaur extinction, they agree that the Chicxulub meteor is at least a partial cause.

I was drawn back into my Costa Rican journals by a curiosity about which, if any, plants could be seen in both Costa Rica and the Yucatan Peninsula of Mexico.  It turns out that most of the Yucatan Peninsula is covered with tropical dry forest, a bit like Monteverde's Pacific slope seasonal forest (but even further on the dry side.)

Plants on the Yucatan Peninsula are often water-stressed for two reasons.  First of all, in the driest part of the Yucatan (the northwest section, where Uxmal is located), the dry season usually lasts for seven months, from October to May.  Meanwhile, the caves underlying the entire Peninsula allow rainwater to quickly filter down beyond the reach of plant roots.

The combination of factors means that many trees on the Yucatan peninsula drop their leaves every year as a water conservation measure during the long dry season.  From a botanical standpoint, though, the Yucatan's dry season is very different from our winter --- although the leaves are gone, the trees often take advantage of the "winter" months to flower and fruit.

The tropical dry forest is also nothing like the rainforest you may picture when you think of the tropics.  Delete the lianas, epiphytes, and towering trees from your mental image and replace them with short trees, parasitic plants and a well developed understory.  Many trees in the tropical dry forest are spiney, and cacti are common --- in fact, the Yucatan has 14 endemic cactus species (meaning that these species can be found nowhere else in the world.)

From a plant's point of view, the Yucatan peninsula is one big island.  Of course, it is surrounded on three sides by water, but the tropical wet forest on the inland side forms just as effective a barrier to plant movement, preventing dry-loving species from gaining a foothold there.  Scientists estimate that up to 10% of the plants found on the Yucatan are endemic, making the area a botanist's paradise.

If, like me, you're just trying to get a handle on what a typical Yucatan forest looks like, you should learn the top species.  The most common trees include Wild Tamarind (Lysiloma bahamensis --- perhaps this is the tree pictured above with the fascinating hairy pods?), Jamaican Dogwood (Piscidia piscipula), Alvaradoa amorphoides, Gumbo Limbo (Bursera simaruba), Cedrela mexicana, Chlorophora tinctoria, Cordia gerascanthus and Lonchocarpus rugosus.  If it helps you make sense of the jumble of scientific names, that list includes three legumes.

Anna:

The continents collided with a vengeance, launching volcanoes that sent molten rock flowing down their sides to cool into islands in the ocean.

Or so I read as we flew south, following the long leg of Mexico down into Central America on our journey toward Costa Rica.

The islands built and merged, until they formed one continuous land bridge connecting North and South America.  At three million years old, Costa Rica is only barely older than humanity, and the country served as the junction of two well developed floras and faunas.  Here, thousands of North and South American species intermingled, interacted, merged.  It was this center of biodiversity I had come to see.

Our journey was my sister Maggie's first foray out of the United States, so I should have been the worldly one, coming to the end of a full year travelling around the world.  But I was terrified of Central America, writing in my journal fears of being "robbed, raped, and killed."  On our first days in Costa Rica, all I thought about was survival.


Maggie:

My expectations were not very clear entering into this foreign land.  I did not know what Costa Rica would be or how it would change me.  Looking back with perspective, I see that I was a tourist and trespasser at first.  Only later, after gazing into the eyes of a girl on the bus to Monteverde, did I put on my new (Vietnamese) sombrero and become Peace Pilgrim, the explorer. 

3-2-01
“I spent an hour or so watching  an extremely cute little girl.  She sat in front of Anna and me, balancing on front of the seat back.  She ate chips and talked to the two blond bunned ladies behind her…  The girl’s face was very expressive and almost always smiled.”

I crashed into this new land speaking bad Spanish and misinformed about so many things.  I used the word “American”  to distinguish myself from the locals, even though their continent was Central America.  I was shocked to see so many “American” things, when what I meant was “Western brands”.  After a point, however, I stared into their eyes enough that I was immersed.  I became a pilgrim or an explorer in this beautiful land. 

I write about the politics of Costa Rica (and the economy), but before coming to Costa Rica, I had never traveled abroad, nor had I experienced poverty to this degree.  I remember how scary and invigorating it was for me to ride on that bus to Monteverde.  It went fast down unpaved mountain roads.  When you are a passenger on a moving bus though, there is little you can do to control how or where you land. 

To the horsetails growing along the shore of the Clinch River, the ancient Arcto-Tertiary forest that gave rise to our cove hardwood community was a recent upstart.  Horsetails’ long slender shoots look like rushes, but the plants are actually close relatives of ferns --- and of the plants that dominated our landscape 300 million years ago during the Carboniferous Era. 

Once again, there were no dinosaurs present, this time because dinosaurs were not yet a twinkle in their father’s eye.  Instead, the animal life at the time consisted of insects and spiders, including dragonflies with three foot wingspans.  The climate was wet and hot, similar to tropical rainforests today, but only the most ancient plants were present.  Ferns, clubmosses, and horsetails dominated the landscape, with relatives of all three growing to tree height.  I like to try to imagine our Common Horsetail growing dozens of feet tall, pushing up toward the sky between ferny fronds of other species. 

If plants could tell stories, the horsetails along the River Trail would tease us with tales of their many-times-great-grandparents whose bodies fell into a massive swamp, pushing down the fallen trunks of horsetails below them.  Unable to decompose quickly underwater, the massive remains of ancient horsetails and their relatives were pressed together into coal.  All of the coal mined in southwest Virginia began as ancient plants, living and dying in Carboniferous swamps 300 million years ago.

Nowadays, ferns and horsetails are small herbs scattered sparsely across the forest floor.  What happened to make the massive ferns disappear? Scientists tell us that different plants came along that were able to reproduce better and faster, pushing the ferns and their allies to the margins.  Ferns and horsetails reproduce using spores, which look like dust to the naked eye and have no room for storage of nutrients to give their offspring a jump-start on life.  When conifers developed, their large seeds gave them a marked advantage over the ferns, allowing conifers to sprout in harsh habitats where tiny fern seedlings would never have been able to gain a foothold.  Of course, even conifers are not our most common plants now --- they were soon overshadowed in turn by flowering plants, a group that encompasses most of the plants on Sugar Hill.  Flowering plants produce showy blooms, most of which attract insects to move their pollen from plant to plant, resulting in even more efficient reproduction.  And so the Common Horsetail ended up a historical side note, diminutive relative of the plants that dominated the moist Carboniferous forests.

In addition to being a great spot to view medicinal plants, Sugar Hill has geological significance.  Geologists divide the earth into hundreds of physiographic provinces, each of which represents a unique land form and helps determine the type of plants and animals which will live there.  Sugar Hill is located within the Ridge and Valley Province, a portion of the Appalachian Mountains where the underlying rocks have been folded like a crumpled up carpet into a serious of parallel ridges divided by long river valleys.  Sugar Hill is wedged into the Clinch River valley north of the Clinch Mountain, a ridge that runs in a nearly straight line for about 150 miles from Burke’s Garden, Virginia, to Knoxville, Tennessee.

Just north and west of Sugar Hill, however, the form of the land changes.  Here on the Cumberland Plateau, the land more closely resembles a crumpled up paper towel with stream valleys running in all directions.  The elevation on the Cumberland Plateau is also higher than that in the Ridge and Valley Province and different plants and animals call this region home.

Ecologists call the border of two ecosystems an ecotone --- for example, the shrubby plants growing along the fence between a pasture and the forest form one type of ecotone.  Ecotones often contain more types of plants and animals than can be found in either of the two ecosystems they divide, a phenomenon known as the edge effect.  So it should come as no surprise that Sugar Hill, located on the border of two physiographic provinces, is home to such a diversity of life.  Keep your eyes open for misplaced Cumberland Plateau species as you hike the trails around Sugar Hill.