IES newsletter

• • •

Newsletter

Volume 4, Number 6
November - December 1987

Director’s Note

The October 4th snowstorm was severe
and left very few people in the mid-
Hudson Valley and western New
England untouched. But was it an
environmental disaster?

Major natural disturbances (such as
windstorms and floods) are not
uncommon. Left to their own devices,
plants and animals adapt to the changed
living conditions, and the system
eventually recovers.

One of the Institute’s goals is to study the
effects of disturbance and the process of
recovery in ecosystems of the
northeastern United States. lES
scientists are already well into an
analysis of the effects of the snowstorm,
as you will see from the following article.

The lES Newsletter is published by
the Institute of Ecosystem Studies
at the Mary Flagler Cary Arboretum.
Located in Millbrook, New York,
the Institute is a division of The
New York Botanical Garden. All
newsletter correspondence should
be addressed to the Editor.

Gene E. Likens, Director
Joseph S. Warner, Administrator
Alan R. Berkowitz,

Head of Education

Editor: Jill Cadwallader
Design and Printing: Central Press

INSTITUTE OF
ECOSYSTEM STUDIES
The New Y ork Botanical Garden
Mary Flagler Cary Arboretum
Box AB

Millbrook, NY 12545
(914) 677-5343

Environmental Disaster?
or “Major Pruning”?

On Sunday, October 4th, over 30 cen-
timeters (12 inches) of heavy, wet snow
fell on parts of the Northeast. Nature is
more or less ready for such a storm by the
time the winter months come, but
deciduous trees are not prepared to cope
with this kind of assault before the leaves
fall from their branches. The weight of so
much early snow on the leaves broke off
branches, split trunks and toppled whole
trees.

Within a few weeks, roadside debris had
been removed, homeowners had cleaned
up their yards, and the thousands of
individuals who had lost power had
restocked their freezers and put away
their candles. But, in the forests, the
effects of the storm remained clearly
evident: pale, jagged scars of broken tree-
tops; “widow-makers” (a term coined by
lumberjacks to describe branches
dangling from the forest canopy) at every
turn; leaf-laden branches on the forest
floor.

Tree damage at the Mary Flagler Cary
Arboretum was considerable. Within days
of the storm, Drs. Steward Pickett, Mark
McDonnell, Charles Canham and Alan
Berkowitz, lES ecologists studying
terrestrial plant communities, put together
a team to assess the damage and lay out a
plan for long-term observations of the
recovery process.

It was important to do a survey
immediately to record what direct effects
the storm had on trees in the various
habitats on the Arboretum, especially in
those areas with a closed or nearly closed
canopy. Ten transects for study were set
up: some in the lowlands, along the flood-
plain of the East Branch of the
Wappinger Creek; some in the densely
wooded area behind the Greenhouse; and
the majority in the Cannoo Hills, both in
forest and Oldfields sites.

The transect lines are 300 meters (984
feet) long. There are 15 points along each,
set at random so that an unbiased sample
is guaranteed. The scientists and their
research assistants selected the four trees
closest to each point for their survey.

They identified the species and noted the
extent of the damage, from no damage at
all, to the number of broken branches, to
total uprooting. The points and the
selected trees were permanently marked,
allowing the scientists to make future
observations of the trees’ growth, health
or mortality.

In addition, at each point along the
transect line a 20 meter (65.6 foot) transect
was placed at right angles. The amount of
debris brought down by the storm was
measured along each of these lines. These
transects will be monitored over a period

of time to find out what normally falls from
the trees as well as what comes down in
storms. These data will show how much
biomass is taken from the forest canopy by
different disturbances.

The piles of debris on the forest floor may
alter the ecology of the area, and the
research team will be in the position to
monitor such changes. For example, slash
piles could provide shelter for gypsy
moths. Gypsy moths are always present in
a forest, but their numbers fluctuate and
outbreaks occur only at intervals. Does an
ecological disturbance have any effect on
the timing of outbreaks? Dr. Clive Jones,
lES chemical ecologist involved in long-
term monitoring of gypsy moth
populations at the Arboretum, will be
assisting in this aspect of the team study.
What if, on the other hand, the piles
provide shelter for small mammals that eat
gypsy moths? lES wildlife ecologist Jay
McAninch will be on hand to contribute to
that part of the research effort.

While some trees may eventually die as a
result of storm damage, from such things
as fungal infections in open wood, most of
the forest will adapt and continue to grow.
The lES ecologists choose to look at the
storm as a “major pruning”, not an
environmental disaster. They feel that for
the next five years or so the major effect
will be the increased amount of light
reaching young trees and shrubs on the
forest floor -- perhaps by the end of that

continued on page 4

lES Plant Ecologist Dr. Charles Canham, right,
and Dr. Steve Pacala, a plant ecologist from the
University of Connecticut, surveying storm
damage.

Forest Response to a Natural Catastrophe

When tornadoes hit the Allegheny
National Forest in western Pennsylvania
on May 30th, 1985, they devastated the
forests on 364 hectares of the 1659-
hectare Tionesta Scenic and Research
Natural Area (900 of 4100 acres). This
freak happening ... such events are
estimated to occur in dense forests only
once every thousand years ... provided
ecologists with a rare opportunity to
learn about the role of natural
disturbance in the dynamics of forest
communities.

Forest ecologists want to learn more
about how trees compete for the
resources of soil, water and light. They
are particularly interested in seeing what
happens to seedlings and small trees
when mature trees are removed from the
forest and are therefore no longer
competing for these resources. Research
on forests, however, poses certain
challenges. Greenhouses provide limited
capabilities for observations of trees, and
most disturbances in nature, such as
forest fires or logging, affect the whole
ecosystem - the soils, animals and lower
plants as well as the tree species. It is
rare that ecologists have the chance to
work in an area where disturbance is
primarily limited to the mature trees.

Tionesta, a small part of the Allegheny
Forest, is one of the few remaining large
stands of virgin forest in the eastern
United States. Hemlocks {Tsuga
canadensis) are dominant, and yellow
birch (Betula lutea), black birch (Betula
lenta), beech (Fagus grandifolia), black
cherry (Prunus serotina) and three
species of maple (Acer spp.) are also
common. During the tornadoes, most of
the mature trees - many of them 300 to
400 years old - were either uprooted or
snapped off to leave only stumps. Young
trees under a meter high (approximately

a yard) escaped the fate of their taller
neighbors, although many were flattened
by falling debris.

Dr. Steward Pickett, an lES plant
ecologist, and Chris Peterson, his
graduate student at Rutgers University,
have taken advantage of the research
opportunities provided by the Tionesta
blowdown. Since July 1986 they have
been observing and recording the natural
recovery processes occurring there.
Three parallel transect lines, one
kilometer (0.6 mile) in length each, were
set up across the 0.5 km wide tornado
path, beginning and ending in the
undamaged forest on either side.
Research plots along these transects
were selected to represent the conditions
of light, soil and drainage typical of the
affected areas. Within the plots, each
plant species and its status were
recorded.

In an undisturbed forest, beech trees are
common as ground cover but grow
slowly in the shadows of taller trees. In
the tornado zone, report Pickett and
Peterson, young beech are now
dominant. However, yellow birch, which
grow slightly faster, and the even more
rapidly growing, but less numerous,
black cherry are starting to provide some
competition. Dr. Pickett feels that it is
likely that in a few years the birch and
cherry will overtake the beech, which
may not become dominant until much
later.

The effects of the white-tailed deer on
regeneration of tree species are also being
studied. These mammals are common is
the Tionesta area. Mr. Peterson reported
in a recent article in the British journal
New Scientist that he has “never seen a
hemlock seedling more than 5
centimeters tall ... anything larger than

that, the deer have already eaten”. Deer
prefer hemlock but also like maples and
black cherry and usually avoid beech;
however, the very dense deer herd has
severely browsed even the beech. Since
beech sprout profusely from the roots,
some manage to “escape” even when
severely browsed. But these young
survivors aren’t “out of the woods” yet:
gypsy moth caterpillars prefer beech,
and Peterson noted that “in a few parts
of the blowdown there are beech with no
leaves at all”. Such interactions are
going to be determining factors in the
outcome of the beech - birch - black
cherry competition for dominance.

In addition to making observations of the
natural regeneration processes at the
Tionesta blowdown, Pickett and
Peterson are manipulating the
environment at selected sites along their
transect lines. Wire fences have been put
around some of the plots to keep deer
away from the growing trees; this
protection will show how great an effect
the browsing mammals have on the
survival of individual plant species. In
some other plots, debris has been
removed so that the ecologists can
compare the growth of young trees in
areas exposed to full light with the
growth of those in areas shaded by
debris.

Pickett and Peterson will record their
observations over a four-year period, and
will need to restudy the site for at least
10 years in order to gain a complete
picture of the early stages in the re-
establishment of a forest. Nature has
provided them with an ideal field
laboratory for studying disturbance and
recovery in an ecosystem, and they are
taking full advantage of the opportunity.

lES ecologists are becoming more involved in
public policy issues - zoning, development,
landfills, atmospheric quality as it relates to
questions on a state level, and others. On October
9th at the Institute, the staff met with profes-
sionals experienced in matters of public policy for
an open discussion of these issues as they relate to
lES research goals. The dialogue will be continued
with relevant members of the Department of
Environmental Conservation staff at a meeting to
be held in Albany. Erom left to right: Nicholas A.
Robinson, Professor of Law and Director of the
Center for Environmental Legal Studies, Pace
University (White Plains, NY); Dr. Richard L.
Ottinger, Professor of Law, Pace University; Dr.
Gene E. Likens, Director, Institute of Ecosystem
Studies; and Thomas C. Jorling, Commissioner,
New York State Department of Environmental
Conservation.

Visitors to lES

Dr. David Grover Frey is an internation-
ally known limnologist who recently
retired as professor of zoology at Indiana
University in Bloomington, Indiana. His
research interests were the developmental
history of lakes and the micropaleontology
of lake sediments as well as the
systematics, ecology and evolution of
cladoceran species (microscopic
freshwater animals related to crabs and
crayfish). Over his years of research, Dr.
Frey built on an extensive pre-existing
Indiana University collection of written
materials dealing with limnology - the
study of lakes, ponds and streams - and
upon his retirement wished to donate the
entire collection to a place where it would
be most useful. He and lES Director Dr.

Gene Likens have been acquainted for
many years, and he realized that the
Institute was the proper home for the
collection. The limnology collection
arrived here in July 1986. It is being
catalogued, and Librarian Annette Frank
reports that is contains approximately
20,000 monographs, serial publications
and reprints in eleven languages. The
collection is not only complete, but also
historically interesting: limnology is a
relatively recent research field in the
United States, but this collection includes
European journals that extend back to the
1930’s. Dr. Frey, a Visiting Scientist at the
Institute, was here in late October and was
photographed (right) with Ms. Frank and
Dr. Likens.

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Meteorologist Dr. Lennart Granat is doing
research in atmospheric chemistry at the
University of Stockholm in Sweden. Early
in November he spent a week at the
Institute, working with Dr. Gene Likens
and Lars Hedin, a Yale University
graduate student doing his Ph.D. research
at the Institute and at the Hubbard Brook
Experimental Forest (New Hampshire).
The three are collaborating on a project to
compare long-term records of
precipitation chemistry in Europe and the
northeastern United States. A discussion
group on acid rain during Dr. Granat’s
visit brought together experts in the field.
Shown here are, left to right: Mr. Hedin;
lES Plant Ecologist Dr. Gary Lovett; Dr.
Granat; and Dr. Charles Blanchard, an
atmospheric chemist at Princeton
University.

Volunteer’s Bequest

lES volunteers are a hard-working, loyal
and supportive group, and their interest in
Institute and Arboretum programs is
frequently broad. This is exemplified by
the case of Miss Dorothy Patricia Hough.

Pat Hough, a resident of Pawling, New
York, did volunteer work in the lES
Greenhouse from late 1982 through early
1985. She enjoyed her work
tremendously, thanks in part to the
excellent tutelage of Greenhouse Manager
David Bulkeley, and her interest grew to
include other lES activities as well. She
asked Mr. Bulkeley how she could help
the Institute, and he suggested that the
Perennial Garden was a worthy cause.

She died in November, 1985. Recently,
lES Administrator Joseph Warner
received formal notification that she left
nearly $250,000 to the Institute,
stipulating that the income from this

bequest be used in support of the recently
completed Perennial Garden. Pat Hough’s
bequest will establish an endowment fund,
the income from which will support a
gardener’s position.

New Staff

JUDIANE KOCH (right), research
assistant I, joined the lES rights-of-way
project in June as a summer field research
assistant. She has just accepted a
permanent position working for Plant
Ecologist Dr. Charles Canham, in which
her responsibilities include coordination of
the Greenhouse research for the rights-of-
way vegetation study and of the project’s
laboratory analysis. She will also be
involved in some field work. Ms. Koch has
a bachelor of arts degree in biology from
Vassar College in Poughkeepsie.

Pruning .. • from page 1

period a casual bystander might not even
be aware that there had been such a storm.
As a result of the baseline studies done in
the weeks following the storm, however,
the ecologists will be in a position to see
whatever lasting effects there might be in
the forest community, and to know how
these changes are related to the October
4th transient event. Relevant findings will
be reported in the lES Newsletter.

Protecting Damaged Trees

Bradley Roeller, manager of display
gardens at the Arboretum, has the
following hints for tree owners who want
to protect damaged trees from possible
infection:

1. Make sure that pruning cuts are made
at an angle, especially cuts that are
larger than 15 cm (6”) in diameter.
Angled cuts will shed water, while flat
cuts will catch moisure from rain, ice
and snow, encouraging rot.

2. Cuts greater than 5 cm (2”) in diameter
should be painted with tree wound
paint, to seal the wood from moisture.

3. Where large sections of the tree are
broken, for example major limbs or
parts of the trunk, be certain that cuts
are made to shed water. Often the cut
has to be shaped to create a ‘drain
spout’.

INSTITUTE OF
ECOSYSTEM STUDIES
The New York Botanical Garden
Mary Flagler Cary Arboretum
Box AB, Millbrook, New York 12545

Newsletter

Volume 4, Number 6
November - December 1987

Winter Calendar

ADULT EDUCATION PROGRAM

The Institute is pleased to announce its winter and
spring semester courses in landscape design,
gardening, botany and ecology;

Winter Semester

Landscape Design I. Site Analysis and Schematic
Design
Graphics
Floriculture

Annuals and Perennials for Landscaping
Growing Herbs Indoors
Intensive Organic Gardening
House Plant Clinic
Spring Semester
Landscape Design Theory
Construction I. Grading and Drainage
Landscape Design II. Plan Development
Drawing for Plan Presentation
Insect Pests and Diseases of Plants
Plants for Landscaping: Woody Perennials
Spring Mushrooms
Frontiers in Ecology
Special Workshops

Plant Propagation and Management for Ecological
Landscaping

Ecological Design and Landscape Restoration
Airphoto Interpretation and Land Use: An
Introduction to Basic Techniques
Planting and Transplanting Trees and Shrubs

For registration information, or to be put on the
mailing list for the Adult Education Program
catalogue, call the Gifford House at the number
below.

ECOLOGICAL EXCURSIONS

Join us for one or more of the following trips:

A Lake in Winter: Frozen Ecology (January 31st)
Winter Ecology of the Bald Eagle (February 6th)
Wildlife in Winter: Bear Watch (March 7th)

The New York Flower Show (March 10th)
Archaeology and Implements (May 18th)

Spirit of Northern Waters (May 20th)

Garden in the Woods (June 9th)

The Ecology of Tivoli Bay: An Exploration by
Canoe (June 11th)

SUNDAY ECOLOGY PROGRAMS

Free public programs are offered on the first and
third Sunday of each month. All programs are from
one to two hours long, and begin at 2:00 pm at the
Gifford House unless otherwise noted.

Jan. 17th: Winter Green: Focus on Conifers (Kass
Hogan) - Walk

Feb. 7th: Vegetation of North and Central
America (Steward Pickett) - Talk
Feb. 21st; Identifying and Controlling Wildlife
Damage in Yard and Garden (Ray Winchcombe) -
Walk/Talk

Mar. 6th: Ecosystem Recovery on Mount St.
Helens (David Wood) - Talk
Mar. 20th: Visit to a Tropical Island (Mark
Mattson) - Talk

For ecology walks, dress for the weather conditions;
wear warm, waterproof boots. In case of inclement
weather, call (914) 677-5358 after 1 pm to learn the
status of the day’s program.

Ecology talks are slide presentations or
demonstrations held indoors at the Gifford House.

GREENHOUSE

The lES Greenhouse performs double-duty: it is a
year-round tropical-plant paradise as well as a site
for controlled environmental research. The public is
invited to explore both aspects during Arboretum
hours. There is no admission fee, but visitors should
first stop at the Gifford House for a free permit.

SCIENTIFIC SEMINARS

The Institute’s weekly program of scientific
seminars features presentations by visiting scientists
or Institute staff. All seminars take place in the Plant
Science Building on Fridays at 3:30 p.m. Admission
is free. For a schedule, contact Julie Morgan at
(914) 677-5343.

ARBORETUM HOURS

Monday through Saturday, 9 a.m. to 4 p.m.; Sunday,
1 - 4 p.m. The Gift and Plant Shops are open
Tuesday through Saturday 11 a.m. to 4 p.m.;

Sunday 1 - 4 p.m. Closed on public holidays. (Also
closed during the deer hunting season and when the
internal roads are snow covered.) All visitors must
obtain a free permit at the Gifford House for access
to the Arboretum.

MEMBERSHIP

Take out a membership in the Mary Flagler Cary
Arboretum. Benefits include a special member’s rate
for lES courses and excursions, a 10% discount on
purchases from the Gift Shop, six issues of the lES
Newsletter each year, free subscription to Garden
(the beautifully illustrated magazine for the enter-
prising and inquisitive gardener), and parking
privileges and free admission to the Enid A. Haupt
Conservatory at The New York Botanical Garden in
the Bronx. Individual membership is $25; family
membership is $35. For information on member-
ships, contact Janice Claiborne at (914) 677-5343.

Tentative schedule (please call (914) 677-5358 to
confirm the day’s topic):

For more information, call (914) 677-5358 weekdays from 8:30-4:30.

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