Dolly Sods

Over the long Labor Day weekend, my fiancée Lily and my friend Seth and I took a three-day backpacking trip in the Dolly Sods Wilderness area of West Virginia:

Dolly Sods is a unique place, a little patch of flora that is more typical of Canada. It sits atop the eastern Continental Divide, and most of the area drains to the Gulf of Mexico via the Ohio River. Parts of Dolly Sods are sparsely treed, and resemble Arctic tundra. It is the easternmost bit of the Appalachian Plateaus province. Many places reminded me of Alaska:

Rolling meadows and bogs occur in patches, interspersed with forest of spruce, hemlock, and aspen (yes, aspen!):

The area was used as a proving ground during World War II, and there are still some dangerous bits and pieces left over from that time:

Here’s our happy trio, ready to set off on Friday afternoon:

Very quickly, I clued into the wealth of small blueberries which were omnipresent in the “tundra” landscapes. I snacked on these continuously throughout the weekend:

A glimpse of two forms of power generation off to the north: Mount Storm on the left (a coal-fired electric generation plant) and a field of windmills on the right:

Here and there, outcrops of white rock rose up above the lichens and shrubs:

This is the Pennsylvanian-aged quartz sandstone of the Conemaugh Group. Occasionally, it outcrops as bedrock, and other times, you just get these clean boulder fields, surrounded by tundra vegetation:

So what do we see when we zoom in on these outcrops and boulder fields? Well, mostly, we see quartz sandstone:

…Although there is a regular smattering of quartz-pebble conglomerate, too:

Occasionally, primary structures jump out at the eye, like some graded bedding…

…or these cross-beds:

Annotated copy:

There were even some fossils, like these plant scraps:

Plant scraps compressed en masse make coal, and there are coal interbeds to be found in places in Dolly Sods, and bituminous coal can also be found as float, as with these chunks:

There was even some structure to observe!

Annotated version:

A bigger outcrop, right around the bend, showed even more pervasive distortion of the sedimentary layers:

Annotated version:

What’s going on with these folds? After all, the Allegheny Plateau isn’t known for pervasive structural shenanigans… I’m guessing this might be soft-sediment deformation: slumping and sliding of sedimentary layers before they got lithified… Any other thoughts? (chime in via the comments section below, if so).

Here is sand weathering out of the sandstone, the grains free and loose again for the first time in ~300 million years:

The plants were a joy:

Here’s the view at sunset from our third campsite:

Yesterday (Monday) morning, when we woke, we found that the temperature had dropped below freezing overnight, and a coarse layer of frost covered everything:

Detail of the frost crystals on my tent’s rain fly:

The sun rose, and starting melting off the frost and dissipating the fog:

Soon only the fog remained:

In the warmth of the new day, we hiked out, got apple dumplings at the Front Porch Restaurant across from Seneca Rocks, and drove back home along good old (new) Route 55. It was a great weekend away, just the right distance, in wild country, with great weather. I felt rejuvenated by the experience.

A day in the field

I spent last Thursday on a long field trip in the Valley and Ridge province of northernwestern Virginia. Leading the trip was Dan Doctor of the USGS-Reston. Accompanying Dan was a UVA environmental science student named Nathan. And the NOVA crew rounded it out: professor Ken Rasmussen from the Annandale campus, associate professor Victor Zabielski from the Alexandria campus, and me. We met at the Survey at 9am, and headed west towards Strasburg, site of my Massanutten field trip.

We started off by examining three Ordovician carbonate units (all above the Knox Unconformity) on the I-81 exit ramp at Route 11. This is the same sequence seen at the classic Tumbling Run outcrop: the New Market limestone, the Lincolnshire limestone, and the overlying Edinburg Formation. We looked at fossils, stratigraphy, some minor structures, and some interesting lithified gunk on the inside of some solution cavities (small caves). Dan interpreted it as collapse breccia: lithified sediment from inside the cave. The question was: when did it form? We wrestled with the best way to test its age, and didn’t come to any clear conclusions. I love moments like that one: out in the field, one geologist shows another something that’s caught his or her attention, and the other geologist reacts, and the two toy with the idea, batting it around like a cat with an unknown object. Like the cat, geologists will either then get really excited and attack the new idea, or get bored, shrug, and walk away.

Our next stop was Crystal Caverns, a commercial cave that is in ownership limbo. Our spirited guide Babs said that it was likely the last time she would lead a tour down in the cave. She was busy liquidating the artifacts of the adjacent Stonewall Jackson Museum, which had recently been shut down by its board of directors. The cave is accessed via a small building that has been built over its mouth. It was a cool cave with a significant 3D aspect: we descended in a corkscrew like fashion, then came back up via a different route. Very cool. A shame that it is being closed (at least temporarily) to the public.

We followed the cave with lunch at a local Mexican restaurant, and while we were there, a big thunderstorm rolled through. Victor, Dan, and I played dueling iPhones to get imagery of the weather front and plot out our plan for the rest of the afternoon.

The afternoon was spent visiting outcrops on the west side of the Great Valley, working our way up to Route 50, and then west to Gore, VA. I wasn’t especially fastidious about photographing everything we saw, but here’s a sample of where I opened the camera shutter…

Ooids in the Conococheague Formation:

Same shot, zoomed in to the middle:

Fossil (blastoid? crinoid?) stem, Needmore Formation:

There were some lovely Opuntia cactus blooming among the vetch at this Needmore outcrop:

From there, we checked out the Chaneysville Member of the Mahantango Formation, where we saw some snail fossils…

…and some spiriferid brachiopod fossils:

Our last stop of the day was at the Clearville Member of the Mahantango Formation, which had lots of lovely coral fossils in it:

Dan put together a Google Map of our 17 stops; if you’re interested in checking out some of these places yourself, then this is a great resource.

I’d like to publicly thank Dan for taking a work day to contribute to our understanding. It was a lot of fun!

Gorgeous poison ivy

Spent the day in the field yesterday with Liz Johnson of James Madison University and her fun group of students in a “Geology of Skyline Drive” summer course. More on the geology later… For now, I just wanted to toss a group of photos of poison ivy up here. Look at this beautiful plant!

Look, but don’t touch!

Bouquet

In honor of Mother’s Day, I offer up an unusual bouquet of flowers…

These are not really flowers, of course, but an odd form of lichen that I found in the Crazy Mountains of Montana last summer, growing on a spruce tree.

Freaky little things, eh? All shots are with the macro function on: the black circles measure about 0.5cm across. Happy Mother’s Day!

The Ghosts of Evolution, by Connie Barlow

Over Snowmageddon, I read Connie Barlow’s book The Ghosts of Evolution: Nonsensical Fruit, Missing Partners, and Other Ecological Anachronisms. [Google Books; Amazon]

Barlow isn’t a scientist, but she’s got a scientist in her pocket: Paul Martin of the University of Arizona. In 1982, Martin and Dan Janzen of the University of Pennsylvania published a paper in Science in which they postulated that a lot of the features of some modern plants are best explained by co-evolution with Pleistocene megafauna (mammoths, gomptotheres, glyptodonts, ground sloths, rhinoceroses, horses, etc.). As those animals are now extinct or extirpated from North America, the plants lack their “disperser” partners. As a result, their “over-sized” or “overly-protected” fruits don’t get dispersed, and tend to rot on the ground. Gravity is the main modern dispersal agent, and so they tend to be quite common in floodplains, but not upland areas.

North American examples of these so-called “ecological anachronisms” are honey locust, osage orange, gingko, pawpaw, Kentucky coffee tree, persimmon, and potentially desert gourds. Another great example, from Central America, is the avocado. These plants bear fruits (or fruitlike growths, if they’re not true angiosperms, like the gingko) which are either very large, very tough, or have very large seeds that are not swallowed by modern animals. Barlow claims that these plants are “haunted” by their departed ecological partners, an evocative analogy that gets repeated many times, long after it’s worn out.

The book is interesting and it held my attention. More importantly, it made me look at the trees around me and wonder at the evolutionary forces that sculpted them, forces now absent, though their sculpture remains. These plants surround us, and one you learn to spot them, it’s hard to pass them on the street without pondering their species’ history.

Walking back to my car after structural geology class at George Mason University last week, I saw some of the pods of the honey locust — big leathery things 15 cm long, 3 cm wide, and 1 cm thick. Some had been cracked open by the pounding action of undergraduate footsteps, and I saw inside the green pulp that Barlow described in the book. I remember she described it as “sugary,” so I grabbed an unmolested pod, and stuck it in my bag. That night, at home, my girlfriend and I cracked it open and tried some. It was sweet! Kind of mango-gummy, I’d say. However, the shell is quite bitter, and so if you try it at home, don’t lick the shell. After I accidentally grazed the shell with my lip and then my tongue, I had to spit and rinse my mouth out. It was nasty.

The Ghosts of Evolution isn’t a perfect book. One criticism I would offer is that it’s a bit repetitive, where the original thesis (a fresh, interesting idea) gets beaten into the ground with endless reiteration. Guns, Germs, and Steel fell victim to the same lack of editorial excision, in my view.

Another problem is that Barlow illustrates her plants with a series of “arty” photographs. The composition of these photos is symmetrical and balanced. They convey beauty, but they aren’t really scientific. Also, the sense of scale she provides is a honey locust seed. This may seem an appropriate sense of scale to a North American botanist, but most of us do not have an intuitive sense of the size of a honey locust seed, even if we are told it’s “about 1 cm long.”

Finally, I would say she needs to be more precise about where the science stops and her own enthusiasm for the idea takes over. The desert gourds she discusses are an exemplar of this: She runs with the idea of ecological anachronisms, and tries to apply its principles to a plant she sees in her own New Mexico neighborhood, but it is unclear how much of this discussion is her own extrapolations and how much has been rigorously researched by botanists. On the other hand, she does things that are beautiful without being scientifically significant: like rubbing a honey locust pod over a mastodon tooth in the American Museum of Natural History, and reflecting how that’s probably the first time that’s happened in more than 10,000 years!

All in all, worth reading if you’re into ecology, evolution, the Pleistocene, or botany. Has anyone else read it? If so, what did you think?