We all know that August is the month when Americans are most likely to take time off and exchange the rigors of the workplace and classroom for those of the crowded interstates and national parks. Well, in my usual contrarian southpawed way, I'm doing just the opposite. This is the month I find myself most at home and in the office -- though I admit that I did just return from one 3,000-mile trip that took me to the Appalachians of Pennsylvania and Maryland and the Pine Barrens of New Jersey. Currently I'm doing just what some of you have been encouraging me to do for several years -- I am busily creating a new adult-education initiative I call the Natural History Exploration Guild. (Or at least that's the working title: I'm told that my original wish, to call it the Impromptu Exploration Company after a long-defunct wildcat drilling firm in western Illinois, suggests a slapdash organizational approach that isn't mine.) After years of speculating on how much I'd like to run my own naturalist-education program, I'm going to actually start it this fall.
Having taught forty-five adult-ed courses at various venues in the past half-decade, I can tell you that it has been a rare privilege to work with hundreds of participating students. Still, I've been aware -- and so have the students -- that something is lacking in at least some of those programs. Applicants eager to broaden their knowledge of natural history -- either on a local or grander scale -- find that the course quality varies widely, and are confronted with rather bureaucratically administered and hidebound academic approaches to that field. For example, they're told that they should take a relatively small dose of introductory botany, followed by a small dose of ecology, followed by a small dose of wildflower identification, and so on and so forth. The problem with this traditionally piecemeal approach, however highfaluting the course titles and however convoluted the system of prerequisites and credits may be -- is that it does not adequately address the fact that all of these subjects are part of one larger subject. It is a depressingly reductionist approach to the one least reductionist endeavor in all of modern science.
Accordingly, I am setting up the Guild in order to offer what I call an integrative natural-history approach -- one that will complement rather than compete with existing education programs by offering courses featuring both classroom and field-trip content that each emphasize the links between different organisms, processes, and concepts in natural history. Here's an example of what I'm driving at. Instead of offering a course in just spring wildflower identification, I'd offer a course in which fall wildflowers, along with their woody-plant and lichen neighbors, are studied as a community that interacts with the soils and geologic it inhabits. Further, we'd discuss how these organisms, and the living community they form, have been used and affected by our own opportunistic species. Does this approach sound nonlinear? It should. Does it sound fuzzyheaded? It won't be. Anyone who is already acquainted with my teaching philosophy knows I'm no fan of the Auntie Mame Rhapsodize-About-Everything-and-Comprehend-Nothing School of nature education. These courses will have meat. They will inspire. They will require a certain heartfelt studiousness. And they will be fun. And ah, yes -- students who complete the curriculum -- currently planned to take most students with other substantial family and professional demands about two years to complete -- will get certification to that effect.
I once read a botany text that mentioned that one particular plant genus (Rubus, for those of you who care), is "currently in the process of rapid evolution." Whether this is really true or not, it definitely describes the status of my fledgling Guild. Probably the best way to see what's in store for this program is for you to take my upcoming and most highly recommended class at Lake Forest Open Lands this September through November. (For more on this groundbreaking, site-oriented course, go to my Courses Page.) Incidentally, for this course and others I will teach under the aegis of other organizations, students also enrolled in the Guild will most definitely get Guild completion credits. So will those folks who attend my weekend-long and mini-trek tours.
You can also keep track of the Guild's progress by visiting the new website I am now building. In a short time, I will send an E-mail update to all members of my subscription list, citing the website's URL and giving you much more information on the Guild. (If you're not already on the subscription list, you can sign up for free by contacting me.) I would love to hear from you about this -- do you have comments encouraging or cautionary? If you are an adult-ed student specializing in natural history in the Upper Midwest, how can I make this program more helpful, educational, and relevant to you? And of course I'd be honored to receive advice from my fellow educators.
And now back to the normal format of this newsletter . . .
PART I. NONLINEAR SOLILOQUIES & SERMONS
A. The CO2 Sermon (the third in a continuing series on the constituents of the atmosphere)
What's wrong with the following statement?
We'd all be a lot better off without that notorious gas we call carbon dioxide; after all, it's largely responsible for the Greenhouse Effect that has caused holes to form in our Ozone Layer. While at present it takes up less than 0.04% of the atmosphere, our supply of atmospheric CO2 is causing the Global Warming crisis that now threatens our world's economic and climatic stability.
I hope this is the most egregiously inaccurate passage I ever write. Perhaps you immediately spotted its most obvious misstatement: the suggestion that we'd all be better off without any CO2 at all. In fact, we wouldn't be better; we wouldn't be here at all. As it so happens, this much-maligned gas is crucial for the process of photosynthesis, conducted by billions of algae, cyanobacteria, and plants, to proceed. And without that almost magical biochemical process -- in which carbon dioxide and water are transformed into sugars and free oxygen with the help of light energy -- we members of the intrinsically parasitic Animal Kingdom would perish, too.
But there are other portions of my beginning statement that should raise the hackles of anyone who has taken a physical-geography course containing a substantial meteorology section (Incidentally, I understand Lake Forest College offers just such a course.) While CO2 is indeed a greenhouse gas, and while its percentage cited above is correct, it isn't the substance that harms the Ozone Layer -- despite what most persons are led to believe. The ozone holes are a troublesome but separate issue, linked instead to our previously wanton use of chlorofluorocarbons, or CFCs. These gases, now banned by international treaty, were once widely employed as refrigerants and spray-can propellants.
In contrast, the problem of Global Warming -- which becomes more and more apparent with every passing decade -- is caused by human industrial, automotive, and agricultural emissions of CO2 and other, non-CFC gases. However, it's the responsibility of every well-informed citizen of this planet to distinguish the specific concept of Global Warming, with all of its potentially dangerous if currently unpredictable consequences, from the more general concept we call the Greenhouse Effect. Far from being intrinsically bad, the latter is one of the physical processes that is normally most beneficial to the survival of life on Earth. Should our level of atmospheric carbon dioxide ever drop significantly, Earth's surface temperature would plummet, the oceans would freeze solid, and virtually all life would disappear in the scenario geologists call Icehouse Earth. So don't curse the Greenhouse Effect. Instead, be concerned with heedless and shortsighted human behavior that generates an excess of CO2. That too-much-of-a good-thing factor is the problem. And that's what we call Global Warming.
B. Ode to South Mountain
In the 1860s, the Earth's human population was a mere one-sixth what it is today. Nevertheless, at that time there was something special happening in the Appalachian Highlands of North America: the aggregation of two very large and mobile herds of Homo sapiens. These herds, which both numbered in the tens of thousands, traveled the Blue Ridge province of Virginia, Maryland, and southern Pennsylvania. One of these vast swarms of humanity was relatively well dressed -- more often than not in mass-produced dark-blue attire. The other looked on average decidedly more casual -- some of its members still had the rudiments of gray jackets or trousers, for instance, but lacked such fashion essentials as shoes. Muddy and heavily calloused feet were wrapped in bloodstained rags or in nothing at all.
On 17 September 1862 the blue and the gray met by a little Maryland stream known as Antietam Creek. In that spot, the dominant landform looming in the east was South Mountain, a long ridge that is one of principal features of the Blue Ridge -- that long, north-and-south zone formed from ancient rocks up to one billion years old. The meeting was not a pleasant one. The two groups, led respectively by Robert E. Lee and George B. McClellan, decided to have a rather disorganized and equivocal battle -- equivocal and disorganized, perhaps, but almost unimaginably deadly. At the end of that one day, approximately 23,000 Americans from both the North and the South were dead, wounded, or missing. The Battle of Antietam -- known in the South as the Battle of Sharpsburg -- was and remains the bloodiest single day in American history.
Stratocumulus clouds over the Chisos Mountains at dusk. In Big Bend National Park, in Trans-Pecos Texas. Here as elsewhere in the Earth's mantle of air, carbon dioxide is present in only trace quantities -- yet it plays a crucial role in the maintenance of life on Earth. (Photo by Raymond Wiggers)
Now a National Park Service property, the deceptively bucolic Antietam battlefield stands in clear view of South Mountain (visible to the east, in the background). This great feature of the Blue Ridge served as a shaper of transportation and settlement patterns and even helped to restrict and channel the ebb and flow of Civil War armies. (Photo by Raymond Wiggers)
About nine and a half months after Antietam, Lee had invaded the North once more, and this time he and his army had slipped all the way into southern Pennsylvania. Once again, the routes taken by both his forces and by the pursuing Federal army were powerfully influenced by Appalachian topography and geology. And by South Mountain specifically, for this high ridge extends northward from Maryland into the Quaker State, where it forms high ground between the towns of Chambersburg and Gettysburg. Lee himself traveled up and over the flank of South Mountain on his way to the latter town. On 1-3 July 1863, the gray and the blue conjoined yet again, with much less equivocal results than were achieved at Antietam. After three days of slaughter the Southern army was decisively defeated and was forced to retreat back across the Potomac River.
The view from the Gettysburg National Military Park observation tower. Here, South Mountain stands to the west; instead of being in the Blue Ridge Province, as is the case with Antietam, this famous battlefield is situated in the Triassic Lowland, where, some 200 million years ago, the supercontinent of Pangea began to rip apart. (Photo by Raymond Wiggers)
Nowadays, one of the best places to explore South Mountain and its geology is near the northernmost extension of the Blue Ridge Province, in the wooded confines of Pennsylvania's Pine Grove Furnace State Park. With a trail map in hand, you can find your way up the relentlessly steep path to the admirably scenic Pole Steeple -- a lofty outcrop of resistant white sandstone of the Montalto Member of the Harpers Formation. This half-billion-year-old rock dates to the Cambrian Period -- the first period of extensive animal remains -- and formed in shallow marine conditions. If you look carefully, you'll find abundant evidence of ancient sea life in the form of long, straight tubes created by worms or other creatures that burrowed into the substrate to escape predators. Dubbed Skolithos by paleontologists, these ancient burrows are trace fossils -- they do not reveal the form of the organisms that made them, but rather something about the creatures' behavior, way of life, or type of locomotion.
Scenes from Pennsylvania's Pine Grove Furnace State Park. Above: a chunk of detached Montalto sandstone with Skolithos burrows, excavated a little more than 500 million years ago by marine animals and subsequently fossilized. Right: the summit of Pole Steeple. Note that the Montalto strata have been tilted by the forces of mountain-building and continental collision. (Photos by Raymond Wiggers)
C. Of Boulder Fields and Ringing Rocks
Any state in eastern North America that has the east-west breadth of Pennsylvania is bound to have plenty of natural diversity. Crossing the state from Philly to Ohio on the Pennsylvania Turnpike -- that overcharged and undermaintained Devil's Racecourse -- one passes through the Coastal Plain, the Triassic Lowland, the Blue Ridge, the Great Valley, the Valley and Ridge Province, and finally the Allegheny Plateau. Each have their own grand geologic story to tell. But Pennsylvania also has a north-south zonation, too -- the northwestern and northeastern portions having borne the brunt of the Ice Age, and the rest being unglaciated. In the places the latest, Wisconsin glacier reached, approximately 20,000 years ago, one can see landscape features reminiscent of the Great Lakes states -- kettle lakes, glacial erratics, terminal moraines, and so forth. But there is one type of Ice Age landform, seen in several locales in Pennsylvania, that are unknown to the Midwestern geologist. These features are boulder fields -- wide expanses containing untold thousands of large rocks. These enigmatic deposits, unlike the much more common aprons of talus (rock debris) one finds on the sides of hills and mountains, are essentially flat and level. How did they get there?
One of the best examples of these fields is found in the Pennsylvania Poconos. at Hickory Run State Park. Here, the boulders are derived from the Devonian-period Catskill Formation -- sandstones and conglomerates formed from the eroded sands and stones of the once-mighty Acadian Mountains. As you carefully step farther and farther out into this eerie, treeless stretch, you can actually hear water flowing at the base of the boulders beneath you.
Geologists surmise that these boulder fields, originally talus on the flanks of nearby ridges, were spread out more evenly in lower areas by the slow but effective process of freeze-thaw. In the harsher and wetter conditions of the late Pleistocene epoch, the yearly cycle of melting and refreezing of water between and under the big rocks actually pushed and distributed them far and wide in the low areas. (Processes similar to this can still be observed in far northern locales today.)
While Pennsylvania's boulder fields are characteristically situated closed to where the Wisconsin ice sheet once stood, there is one oddball exception located to the south of the glaciated part of the state, in the Triassic Lowland. This is the locally famous Ringing Rocks County Park -- the county being Bucks, just a short distance from the Delaware River north of Philadelphia. Here the boulders are made of a much harder, igneous rock called diabase. This rock formed when magma welling up from the Earth's interior during the rifting and breakup of the supercontinent of Pangea cooled close to the surface. In this particular park, the boulders are said to produce a variety of ringing tones when struck with a hammer. Personally, I've heard many other rocks ring, thud, thonk, and even groan a bit when hammered, but I'll let you judge the aesthetic qualities of this musical boulder field yourself. I here inset two short .mpeg clips, which may be easier for some of you to play on your PC than others. If you do get these clips to play -- be patient while they load! -- let me know whether you were deeply moved by the concert soloists' interpretations.
The Hickory Run boulder field in northeastern Pennsylvania. (Photo by Raymond Wiggers)
Here your newsletter author plays a cadenza for the left hand; Dr. Timothy Morton, of the Ursinus College Biology faculty, provides the coda at the very end.
Tim Morton demonstrates different tones produced by different boulders; he's accompanied in the background by somewhat younger kids with their own hammers.
PART II. UPCOMING EVENTS
Tours.Dispel those Late-August Blues by taking one of my two-hour Mini-Treks! Also, keep in mind that my most popular weekend trip is coming up -- the one to the Baraboo Hills and Driftless Area of southern Wisconsin, in the first week of October. The fall foliage colors should be splendid then. To get a fuller description of this tour to a geologic and botanical wonderland, and to request a trip prospectus, visit my Tours Page. And if you can, attend the Nachusa Grasslands, Marengo Ridge, and Hyde Park tours I'm doing this fall! They, along with the Mini-Treks, are listed on the Tours Page, too.
Courses. If you want to see what the integrative approach of my new Natural History Exploration Guild involves, enroll now for the Lake Forest Open Lands course devoted to three of the Illinois North Shore's finest ecological restorations. For more information, go to the Courses Page.
Looking across Devil's Lake at the West Bluff, the Southern Baraboo Range, Sauk County, Wisconsin. Note the massive deposits of quartzite talus on the bluff slope. You'll see this view yourself -- with the added attraction of fall foliage colors -- if you attend my weekend trip in early October. (Photo by Raymond Wiggers)
Lectures. I'm back on that long but fulfilling road as a public speaker! This fall, some of my free talks are at hosted by libraries and geological societies; others are held in conjunction with Hyde Park Historical Society and McHenry County Conservation District hikes. Go to my Lectures Page for more on all of these.
PART III. REVIEWS OF BOOKS AND VIDEOS
This section is on summer vacation. I've been reading books on other subjects. Reviews will resume in the next issue.
PART IV. THIS ISSUE'S PARTING QUOTATION
"The public demand that every man remain in his own field. Nowhere would anyone grant that science and poetry can be united. People forgot that science had developed from poetry and they failed to take into consideration that a swing of the pendulum might beneficently reunite the two, at a higher level and to mutual advantage."
- Johann Wolfgang von Goethe
May your final weeks of summer be happy and productive ones for you all.
Best regards,
Ray Wiggers
Gentianella quinquefolia var. occidentalis -- one of the rarer gentians in bloom in Lake Forest's Shaw Prairie during our upcoming Open Lands course. (Photo by Raymond Wiggers)
