Volume 16 Issue 4 Autumn 2014 SHOOTING THE BREEZE A Publication of Bull Run Mountains Conservancy, Inc. A Geologic History of the Bull Run Mountains As the leaves continue to drop from the trees, the landscape seems to change from an ocean of green vegetation to one of grays and browns and of rocks and wood. It is the time of year that old home sites are clearly visible along with the scars of past land use. As we look at these humanaltered landscapes that are now forested over, it is almost impossible not to reflect on how the underlying geology is not only the shaper of the woods today, but also the determiner of how the land was used by humans in the past. By Michael Kieffer lies on the western edges, the younger thinner bedded quartzite (flaggy-quartzite) lies on the eastern slopes, with the now metamorphic basalt (greenstone) exposed on the valley floors within the BRM and forming the hills to the west of the BRM. This is an oversimplification of the geologic processes that created the BRM, but gives us an idea of how they formed. It also speaks to the human history. If the vast majority of the BRM is a metamorphic sandstone, the soils it creates will It’s a billion years ago, and there are mountains at be dominated by sand. Thus the plants that grow least 25,000 ft. high on it will be able to live with (Grenville Range) located little nutrients and dry about where the present conditions. It also means Blue Ridge Mountains are that farming would be today. There is no life on impossible except in the land, and beautiful white valley floors where sands are pouring off the greenstone is present. The mountains and piling up mountains would be left to where the Bull Run hunting for the American Mountains (BRM) sit today. Indians, to timbering by the It is like Clearwater Beach. early land barons, and Eventually, the sand is eventually to squatting by buried by more material those who worked for from that ancient mountain range, and the landowners whose estates surrounded the pressure becomes great enough to turn it into mountains. sandstone. Flash-forward to 550-600 million years ago (mya) and volcanoes are erupting and The technical geology of BRM: Bull Run belching out basalt as the continental plates shift Mountains (BRM) stand alone as a narrow, forming the Iapetus Ocean, the pre-Atlantic. Some monadnock-like series of ridges, and comprise a of this molten rock will squeeze between the prominent, isolated area of rugged highland layers of sandstone forming the beautiful igneous terrain within the gentle, lower-lying Piedmont. rock we know as quartz, the veins of which we This highland complex extends north from New can still see in the rock outcrops on top of High Baltimore in Fauquier County for approximately Point. Move forward in time to 500-550 mya and 15 miles to Aldie in Loudoun County, varying the beautiful white sandstone is being from about 0.9 to 2.2 miles wide and rising metamorphosed, due to heat and pressure of the conspicuously above the surrounding terrain material above it, into quartzite, a metamorphic (Fleming, 2002). sandstone (metasandstone). Jump now to 230 mya. The pre-Atlantic has disappeared. Africa is While occupying the physiographic Piedmont, colliding with North America, and the present day BRM form part of the eastern limb, or flank, of the Appalachian Mountains are being created. The Blue Ridge anticlinorium, a large fold that Bull Run Mountains mark the eastern edge of this presumably resulted from Late Paleozoic mountain range. The oldest rock, the thickest Alleghanian orogeny. BRM are largely underlain bedded metasandstone (Weaverton quartzite) by metasedimentary rocks of (continued on pg. 5) From Field to Pen SHOOTING THE BREEZE is a publication of Bull Run Mountains Conservancy, Inc. Board of Directors President Andrea Currier Vice-President P. Douglas Fout Treasurer Sandra Kleiman Secretary Marcia Markey Lavinia Currier Kathleen Higgins Jack Kotz David Roos Jonathan L. Shurberg Counsel John McBride Staff Executive Director Michael J. Kieffer Intern Anna Ritter by Anna Ritter Over this past summer, Gary Fleming from the Department of Natural Heritage, Michael Kieffer from Bull Run Mountains Conservancy, and I hiked across the length of the Bull Run Mountains—leaving early morning for the gravel back roads and returning sweaty and tired but successful after another day of resampling vegetation plots. In total we permanently remarked and resampled 40 plots on different areas of the Bull Run Mountains Natural Area Preserve. These plots serve as baseline data on the vegetation for future studies, so trends can be analyzed across the years. As Fleming heads back to his office to formally analyze the results, I shall informally compare what I observed with what Fleming recorded in his original 2001 study as well as with the study botanist H.A. Allard conducted during the 1930s and 1940s. I shall also discuss a major overlying theme apparent in the analyses of the plots—how ecosystems work in a harmonious cycle, with all parts interconnected. When Fleming recording data part of that cycle is removed or influenced, it skews the rest of the system, creating a watershed of reactions. Fire When Allard presented his study on the vegetation of the Bull Run Mountains (BRM) in the early 1940s, he commented on the presence of fire. In the early stages of succession from field to forest, occasional fires cleared the fields of shrubs and small “invading conifers,” resulting in a landscape comparable to an eastern prairie of tall grasses in existence over an extended period of time (Allard, 1943). Historically, fire has always been a factor of every landscape. Native Americans used fire in hunting to flush out game from the forest understory, and it occurred naturally through things like lightning strikes. With the sprawling suburban population, fire prevention efforts turned into fire suppression in an effort to protect homes. The result has been that fire has virtually vanished from the landscape. Without fire, a noticeable layer of duff (old leaves, needles, small sticks) has built up which fire would otherwise normally burn away. This has profound ramifications particularly for pine and oak forests, which “developed under a regime of frequent burning” (Fleming, 2002). Fire removes duff layers to make way for the growth of mosses and lichens and thins out competitors like the red maple that crowd out oaks (Allard, 1943). Fire especially rejuvenates the pine forests, as pines sprout from burned stems and certain pine cones only go to seed after exposure to flame. This summer we found the duff layer was disproportionately large, strangling the growth of new pine seedlings, and blueberry and huckleberry underbrush was prolific. Even in the 2001 study, Fleming reported the increase of red maple and American beech, and this summer pines on certain ridges had begun to die out. Deer By the 1930s, about the same time Allard was studying the BRM, many of the large mammals of the eastern states had been driven near extinction due to overhunting and the effort to protect livestock and crops. This impact included wolves, coyotes—and white tailed deer. Over the latter part of the century, however, efforts to restore the landscape with regards to deer included regulations on hunting and even shipments of deer to boost their population. Unfortunately, as no one wanted to ship wolves back as well, the deer population increased exponentially, unchecked by any natural predators. This was apparent on the landscape this summer as vegetation which would normally have been full grown or in flower were eaten back severely and sometimes simply gone from the area. Solomon’s Seal, for instance, blooms during the summer and reaches heights of two feet. We, however, only found it as small sprigs and encountered it in bloom only once. Invasives Also a factor in altering the landscape, in perhaps the most obvious way, is invasives. Ever since explorers first arrived in the 1400s from Europe and the transference of animals, plants, and diseases began in the Columbian Exchange, foreign plant species have constantly battled the native species. Coffee, tobacco, rice, and indigo were some of the main and purposeful plants brought to North America and the Caribbean and were used as exports and “cash crops” for (continued on pg. 4) Public Programs Autumn/Winter 2014/15 TRAIL WORK SATURDAYS—DATE CHANGED! 2nd Saturday of Every Month 9 a.m.—1 p.m. Join us in our efforts to improve and maintain the trail system on the Mountains. Every month volunteers leave a lasting impression on the Preserve and have fun doing it! Don’t forget this event has changed to the second Saturday of the month. AMPHIBIANS OF SPRING March 4th, 2015—Wednesday, 7–9 p.m. Last year we found hundreds of spring peepers, upland chorus frogs, wood frogs, and spotted salamanders along with lots of egg masses. Grab your red lights and boots. Let’s see what we can find this year! Pre-registration required. Members: $10/non: $15 HIKE WITH A NATURALIST 1st Wednesday of Every Month 9 a.m.—11 a.m. Our first Wednesday of the month hike for those members and nonmembers who prefer to hike in a group. Come and discover some of the flora and fauna of the Bull Run Mountains. This program is free; all are welcome. WOODCOCK WATCH March 7th, 2015—Saturday, 5–9 p.m. Join BRMC and Environmental Studies on the Piedmont for an evening stroll and sit to enjoy the American woodcocks’ spring territorial and courtship flights. We will meet at Clifton Farm at 5 p.m. to watch American woodcocks perform flight displays that would amaze any world traveling birder. Pre-registration required. Members: $10/non: $15 HOMESCHOOL PROGRAMS This autumn and winter, BRMC will be continuing its popular classes for homeschoolers. Pre-registration is required. Cost: $5 per participant including adults. HOPEWELL OBSERVATORY TBA Join us for an evening of stargazing at Hopewell Observatory. Jupiter and some spectacular deep sky objects (Orion nebula and the Pleiades) will be up in the night sky. Dress warmly. Bring flashlights (red light preferred but not necessary) and water. Event subject to clear skies. Space is limited. Pre-Registration required. Members: $15/non: $20 Adaptation and Winter Woods January 7th, 2015— Wednesday, 10 a.m.—12 p.m. Explore the Bull Run Mountains in winter and learn how plants and animals survive the cold and (hopefully) snow. You will observe how life stages of living organisms are adaptations for the survival of both adults and offspring and OLD HOMESITES BREAKFAST how organisms are adapted to survive through seasonal April 25th, Saturday, 8:30a.m.-11a.m. changes. All ages. Go beyond the trails as we explore cemeteries, foundations, and clearings that mark past residences. Then enjoy a hot Birdhouse Workshop breakfast in the woods as Marcia Markey, a local historian, February 11th, 2015—Wednesday, 10 a.m.—12 p.m. We will discuss cavity-nesters’ habits and habitats and learn performs an historical reenactment based on diaries, letters, and other primary sources. Space is limited and spots fill why they are an important part of the ecosystem. It has early. become harder for these birds to find suitable nest sites Pre-registration required. because of loss of habitat—build a birdhouse and help increase their populations while attracting these beautiful Members: $25/non: $30 creatures to your backyard for a close-up look. All supplies Register at www.brmconservancy.org will be provided to build cedar bluebird boxes. (There is an additional charge of $20 per participant for this program to cover supplies and preparation.) Best for 3rd grade and up. OLD HOMESITES EXPLORATION HIKE February 7th, 2015—Saturday 9a.m. –1p.m. BRMC is excited to expand our Old Homesite Program with a winter hike to cemeteries and old home sites well off the beaten path. If you ever wanted to explore more of the preserve beyond the trails, this is your chance. Pre-registration required. Members: $20/non: $25 Gary Fleming & Michael Kieffer –Plot Studies Field to Pen (cont.) (continued from pg. 2) European nations. In fact Kudzu itself was brought purposefully and used by farmers to control soil erosion on their farms (The Nature Conservancy). Japanese Stiltgrass, however, arguably one of the most prevalent invasives in our area, was brought over as packing material for porcelain (NYIS). Now one can recognize its light green carpet in forests across the eastern states. Reaching anywhere from 1 to 3 feet tall, the grass has thin stalks with small, flat, alternating leaves—almost a miniature bamboo (The Nature Conservancy). It can spread Stiltgrass carpeting the forest floor nearly everywhere: if you have ever noticed dead-brownish spots in your lawn in early fall that is stiltgrass, dying back before the wanted grass species. Like all invasives, the grass has nothing to check its advance. It is not eaten by anything—not even the white-tailed deer; it thrives in a diversity of conditions from woods to fields; and the climate suits it well as the North American and Asian hemispheres correspond closely. Thus stiltgrass overwhelms the native species which do have natural checks. Although having only been introduced here during the 1920s, with Allard making no mention of it in his study, by 2001 Fleming had noted its presence. And this summer the grass had begun to appear in previously unaffected plots. Conclusion Managing any of these three factors presents their own respective challenges. The lack of fire is probably the easiest to remedy as it simply requires the reintroduction of fire in the form of prescribed burning. A controlled burn stays in the understory, burning off the duff layer and removing underbrush—like weeding out a garden. The huge canopy fires of the west are of course Photo credit: Emma Burgess not on the list, although interesting observations in Australia have seen forests recovering much quicker than thought possible, as well as the flowering of some species which occur only in the wake of such devastating fires (PBS, Survivors of the Firestorm). Deer offer a more complicated challenge. An interesting observation this summer was that the ridges where hunting has been allowed for years showed even greater browse damage than previously. To test whether this was correlated or simply a coincidence would require further investigation, but handling the deer population is a top priority. Japanese Stiltgrass invasion is also a major concern. As the seeds can remain dormant for up to seven years, removal is a long, arduous process, although doable. Hand pulling for small areas, mowing before the plant goes to seed, and chemical treatments are all current tactics endorsed by the Pennsylvania Department of Conservation and Natural Resources and the National Park Service. BRMNAP’s ecosystems are biological communities of interacting organisms and their physical environment. Aggravating parts of the system causes changes which are reflected in every aspect. Recently, a BRMC member e-mailed a short video about wolves in Yellowstone, called “How Wolves Change Rivers” by Sustainable Human. It follows the reintroduction of wolves in the park, and reveals how one species can have such a profound impact to the point of even rerouting a river. Removing a species, removing a natural process like fire, introducing a foreign species—it all resounds down the chain to affect the entire system. And this summer, we got a glimpse into just how this process is happening on the Bull Run Mountains. References: Fleming, G.P. 2002. Ecological communities of the Bull Run Mountains, Virginia: baseline vegetation and floristic data for conservation planning and natural area stewardship. Natural Heritage Tech. Rep. 0212. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond. Unpublished report submitted to the Virginia Outdoors Foundation. 274pp. Plus appendix . Allard, H.A., Leonard, E.C. “The Vegetation and Floristics of Bull Run Mountain, Virginia.” Castanea. 8.1-3 1943. Japanese Stiltgrass. The Nature Conservancy. Online. Japanese Stiltgrass. New York Invasive Species Information. Online Survivors of the Firestorm. Nature. PBS Videos. Online. Geologic History (cont.) (continued from pg. 1) the Chilhowee Group. Massive, thick-bedded quartzite, from the Weaverton Formation, is erosion resistant and well exposed as it sloughs off the upper west slope of High Point Mountain north of Thoroughfare Gap, and at White Rock north of Hopewell Gap. The strongly eastward-dipping quartzite strata are powerful ridge-forming features. The eastern dip slopes of the ridges are underlain by thin-bedded quartzite with local interbeds of muscovite schist and pyllite. The Catoctin Formation underlies the lower to middle western slope of the Bull Run Mountains, but is generally covered by quartzite-based colluvium (Leahy, M.J. and S.Y. Erdle, 2004). The Bull Run Mountains are remnants of an earlier erosion cycle that occurred when the whole Piedmont was level with their summits. The Piedmont presently is a series of rolling hills dissected by streams and rivers. A plain that is not yet worn entirely smooth by the agents of erosion is geologically called a peneplain. Classified as monadnocks (isolated hills of resistant rock rising above the peneplain), the resistant metasedimentary rock at its highest point is 1,369 feet in elevation, with the peneplain on the western and eastern flanks at approximately 600 feet and 400 feet, respectively. The high, nearly vertical cliffs at Thoroughfare Gap, High Point, and White Rock are unique Piedmont features. In addition, many small quarry operations exploited the geologically younger, thinner bedded “flaggy” quartzite found on the eastern slopes that were used for building stones and flagstones, providing a significant input into the local economy. References: Fleming, G.P. 2002. Ecological communities of the Bull Run Mountains, Virginia: Baseline vegetation and floristic data for conservation planning and natural area stewardship. Natural Heritage Technical Report 02-12. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, Virginia. Unpublished report. 276 pp plus appendices. Leahy, M. J. and S.Y. Erdle. 2004. Management Plan for Bull Run Mountains Natural Area Preserve. Natural Heritage Technical Report #04-09. Virginia Department of Conservation and Recreation, Division of Natural Heritage. Richmond, Virginia. 71 pp. plus appendices. To register for a program, fill out the form below and mail with your payment to: Bull Run Mountains Conservancy, P.O. Box 210, Broad Run, VA 20137 Program registration is also now available online at www.brmconservancy.org/calendar.html. For more information, call us at (703) 753-2631 or visit our web site at www.brmconservancy.org. Name _______________________ Address ______________________ City/ZIP ______________________ Home phone __________________ Work phone __________________ E-mail _______________________ Are you a BRMC member? ______ No. of people registering ________ Fee _________________________ Amount enclosed _______________ Name of child[ren] if registering for youth camp ________________________ ____________________________ Homeschool Programs $5 per participant, including adults Woodcock Watch March 7th Members: $10/non: $15 Adaption and Winter Woods, Hopewell Observatory January 7th TBA Members: $15/non: $20 Birdhouse Workshop, February 11th Old Homesites Breakfast $20 additional charge April 25th Members $25/non: $30 Old Homesites Exploration February 7th Members: $20/non: $25 Amphibians of Spring March 4th Members: $10/non: $15 Bull Run Mountains Conservancy is a membership driven organization. Yes, I would like to become a member of Bull Run Mountains Conservancy. Name _______________________________________________________ Organization _________________________________________________ Address ____________________________________________________ ____________________________________________________________ Phone _________________________ E-mail _______________________ Become a member today and support our programs and support the public preserve. Your membership provides BRMC necessary funds to operate and shows our foundation and corporate supporters that the public values and appreciates the resource. Referred by _________________________________________________  $15 Student $20 Senior $25 Individual $35 Family $75 Group $100 Sustainer $300+ Leadership $1,000+ Benefactor $1,000+ Corporate $5,000+ Conservation Patron   Other_______ Adaption and Winter Woods Old Homesites Exploration Birdhouse Workshop Amphibians of Spring Hopewell Observatory Woodcock Watch Old Homesites Breakfast Directions: January 7 February 7 February 11 March 4 TBA March 7 April 25 Unless otherwise noted, all programs and events will meet at the BRMC Mountain House at 17405 Beverley Mill Drive in Broad Run, VA, across from the Bull Run Mountains State Natural Area Preserve trailhead. Take I-66 to Haymarket exit. Go south on Rt. 15. Go west on Rt. 55 for 2.7 miles. Turn right on Turner Rd., then left on Beverley Mill Dr. to the Mountain House 3/4 mi. on left. Call (703) 753-2631 for more information or visit our Web site at: www.brmconservancy.org 2015 Calendar of Events  Bull Run Mountains Conservancy Please make your tax-deductible contribution to: Bull Run Mountains Conservancy, Inc., P.O. Box 210, Broad Run, VA 20137 Membership Benefits: Support environmental and historical programs for all ages Support research and management of the natural area Discounts on all public programs and camps Quarterly newsletter including our program calendar
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