All summer I’d put off going on local collecting trips, primarily because the Ohio temperatures were in the high 90’s nearly every miserable day. My Nevada trip plans fell through as several events dissolved any opportunities to return to last year’s exciting sites.  Finally as summer was ending, I still had not gone out once!   A call to my trusted partner Ron Rea quickly set up what we’d hoped would make up for lost time - a 4 day trip in the eastern US.  Another set of phone calls gave us access to a private dig site in Virginia.  On the way home we’d examine the myriad of roadcuts that border the roads from Virginia all the way into Tennessee.

            Ron bravely drove his truck on this journey.  Our history of flat tires and vehicle trouble is one that is hard to forget.  Forecasted temperatures were for upper 90’s both in Ohio and Virginia.  Humidity was so high that we could barely see the forested green Appalachian Mountains.  Arriving in Roanoke, Virginia after a 6 hour drive, we secured 2 motel rooms and traveled to the landowner’s home to finalize our permission and plans.  Mrs. C has lived on this property her whole life and truly cherishes her personal trilobite exposure.  As always, she loves to talk about the site and the things she’s found.        
     
     The next morning Ron drove the truck through the front gate and along the path as I walked ahead, opening and closing gates.  After passing through the gauntlet of gates and reluctant groups of bovine we arrived at the shale outcrop, a small exposure in the middle of a cow pasture (complete with cows.)  Dense fog hovered just above the ground creating a surreal view of the valley. 

            We are collecting in the lower Middle Ordovician Liberty Hall Shale, the upper portion of the Edinburg Formation.  Fossils are uncommon except in widely scattered pockets.  This particular exposure is a lagerstaaten of remarkable preservation.  The site is only about 10 X 10 meters; however the density and quality of specimens yield a large number of complete trilobites including Ampyxina powelli, and rarely Edmundsonia typa, Dionide holdoni, and Porterfieldia caecigenus. Fragments of Robergia and the cheiurid Calliops have been found.  Also found are huge numbers of graptolites and less commonly brachiopods, tiny gastropods, cephalopods, and trace fossils.  Many other species of trilobites have been recorded from the Liberty Hall Shale, however this particular site does not have the species diversity that is known from other localities.

            The shale lies at roughly a 45 degree angle.  Since cows are actively wandering around as we work, extreme caution had to be maintained to insure no hole was big enough to harm the animals should they stumble in.   So unlike a typical dig where we would clean off a nice exposure and work a bench deep into the ground, here we kept the holes small and simple.  Fractures and partings run throughout the shale, so it was just a matter of exposing the shale and pulling out the chunk.  Then we split it as completely as possible.

            The rock alternates from nicely laminated shale to nodular mudstone to a nasty storm hash layer.  The Ampyxina seem to predominate in the clean shale while the Dionide are associated with the mudstone.  Graptolites appear at every level and layer.  At the edge of the exposure in finely laminated shale rare Porterfieldia, a Triathrus-like trilobite, were found mixed in with a plethora of graptolites, but associated with no other trilobites.

            Ron and I immediately began finding Ampyxina. They are small, most measuring 10 mm or less.  A complete juvenile possesses a long “nose” spine; the adults do not have the anterior spine. A typical specimen has very thin shell, presenting itself as a positive/negative cast.  The trick was to find a complete one with good, thick shell that was not fragmented between the positive and negative.  The lace-collar trilobites – the Dionide and Edmundsonia - tended to have sturdier shells and split out much nicer.  Some of the Dionide were tiny, however I found a couple that measured 25 mm. The Edmundsonia often possessed long genal spines.

 By 9 am the sun burned through the fog and quickly heated the countryside.  Thistle was in full bloom and hundreds of butterflies  flew from flower to flower, keeping the meadow in constant motion.  Looking out, I could see  the long parallel mountains on my right and left, the lush emerald valley of farms and woodlands extended in between. After a couple hours of kneeling and bending over the shale, a stroll through the meadow offered a pleasant break for both the mind and body.  By the end of the day I took over 100 digital pictures of butterflies and flowers, trying to capture that indescribable feeling of peace within the meadow.

The intense sunshine through the haze created increasingly uncomfortable conditions.  The thermometer on the truck read 98 degrees.  We set up a canopy to afford us a little bit of shade.  The cows migrated to a nearby stand of pine trees.   And suddenly we had several large insects  loudly buzzing just past our ears.  At first I thought they were cicada killers, a large type of hornet.  After 5 minutes of cringing and trying to avoid these creatures, I spotted one that crash-landed in the pasture.  I crept up to it and to my amazement, it was a huge, metallic green beetle!  It was digging into the soil and quickly buried itself.

I have collected this site previously, and the one bug I really wanted to find that I have had absolutely no success was a complete Porterfieldia. Up to this moment, I’d yet to find even a fragment.   Literature indicates I should find Porterfieldia as well as some other unusual species. 

            Early in the afternoon 3 children came through the pasture to visit us and to see what we had found.  They knew all about the trilobites at this spot, and after introductions they began to pick around on the surface.  The youngest of the children was a girl about 4 years old, the others being about 7 and 12.  One at a time the two oldest children brought fossils they found, usually graptolites or fragments of weathered Ampyxina.  Ron and I enjoyed the kids and their enthusiasm, though we wearied looking at their fossils over and over and over again.  Then for the first time the youngest came to me and said “Look at my fossil.”

            I reached for it and after my eyes rejoined my head, I said “How would you like to trade this fossil for a really nice pretty one,” and I offered her a very nice Ampyxina.  Ron spoke up from the shaded canopy, “Young lady,  I’m not sure what you gave him, but you better ask him for two trilobites in trade!”  Yep, that little girl laid into my hand a  negative to a complete Porterfieldia!   I asked her to think very carefully to remember where she found this fossil.  She walked around thinking it was here, then there, then another place, and finally she settled on a spot on the fringe of the shale exposure.

            Not wasting time, I moved over to that area and began to poke around, immediately finding 2 partials!  After working through the top, weathered shale, I found a solid chunk of shale and pulled it out.  It was solid and did not want to split, in spite of the obvious multiple laminations.  Using a tiny chisel, I split the chunk.  The negative showed 2 complete Porterfieldia!  I picked up the positive and wanted to cry – the chisel went through both bugs.

            I worked the shale from this spot for more than an hour with nothing to show but several partial Porterfieldia and thousands of graptolites. Finally I split out the right piece of black shale and out popped a perfect, white Porterfieldia!  By the time the little girl left to go home, she had all sorts of fossil rewards to add to her collection!

            By 6 pm, Ron and I both had filled all the flats we brought on the trip to store specimens.  We filled 5 gallon buckets with shale chunks that would split further after weathering.   The heat and humidity was overwhelming.  We wanted to return the next day, however we had to think about how much room was remaining in the truck, as well as whether we wanted to deal with the weather, which was predicted to be the same or even more oppressive. 

Under a reluctant but agreeable consensus, we decided to quit and head home the next morning.  We made sure the shallow holes we created were completely filled in.  The cows came out from the trees as we policed the area as if checking our work.  Then we eased our way back down the path to the main road.

Mrs. C was anxious to hear how we did.  She spoke again of many of her excellent finds, most having been recently donated to a local university.  I can think of no finer landowner who heartily appreciates and understands the significance of the exposed rock on their property.  We thanked her again for her wonderful hospitality and then headed for our motel.  The air conditioners barely worked, but we were so hot that any coolness seemed like Heaven.

On our journey home we drove the backroads looking for roadcuts, however the State of Virginia made a concerted effort to plant crown vetch to hide those unsightly rock exposures.  Perhaps during the winter months the roadcuts can be collected, but not during summer.   We finally gave up and drove home on the interstate.  The temperature hovered around 100 all the way home.  But there is nothing like a terrific rare find to make a long hot trip home tolerable.

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