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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