Newsletter

Volume 4, Number 4
July - August 1987

At the Arboretum ...

Work on a “Pollution Garden”, the
second lES Research Display, has been
in progress since late spring. This living
display shows the effects of air pollution
on sensitive and resistant plants.

The Fall Adult Education Program
brings new courses, workshops and
excursions. See our catalogue!

Sunday Ecology Programs are held on
the first and third Sunday of each month
(except holiday weekends).

ilH 4c 4( 4c

See the Summer/Fall Calendar on the
last page of this Newsletter for
information on all of our current public
programs.

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 York Botanical Garden
Mary Flagler Cary Arboretum
BoxAB

Millbrook, NY 12545
(914) 677-5343

International Ecology Conference

Ecologists are increasingly aware of the
importance of long-term studies in gaining
a better understanding of ecological
phenomena. On May 10th, 1987, sixty-one
eminent ecologists from eleven nations
gathered at the Institute of Ecosystem
Studies for the Institute’s second Cary
Conference. By the closing session on May
13th, this body of scientists had endorsed
a far-reaching statement of the need for
sustained ecological research.

The importance of long-term studies to
society becomes clear when one looks at
current problems. For example:

* Acid rain in North America was
identified by lES Director Dr. Gene E.
Likens and colleagues in the course of
their long-term research at the Hubbard
Brook Experimental Forest in New
Hampshire.

* Long-term studies demonstrated that

continued use of ammonium fertilizers
had the detrimental effect of acidif 3 dng
soil.

* Have you wondered what the benefits
are from using unleaded gasoline in cars?
Long-term research has demonstrated
declining concentrations of lead in the
environment following the reduction in
use of leaded gasoline.

* Detection of the “greenhouse effect”, a
phenomenon caused by gradual changes
in the amount of carbon dioxide in the
atmosphere, was possible only through
observation over long periods of time.

* The consequences of the introduction of
a new animal species into an area - such
as the gradual movement of the Ljone
tick outwards from its point of discovery
along the New England shore - is best
understood by doing careful measure-
ments year after year.

continued on page 3

Perennial Garden Dedicated

For several years, visitors to the Mary
Flagler Cary Arboretum have watched the
development of the Perennial Garden,
located at the Gifford House Visitor and
Education Center. On June 27th, 175
Arboretum members arid friends attended
a ceremony to formally dedicate this
public garden.

Speakers at the dedication were Dr. Gene
E. Likens, Director of the Institute of
Ecosystem Studies and of the Arboretum;
Dutchess County Legislator Ann L.

Loedy; Town of Washington Supervisor
Augustine Rotunno; Millbrook Mayor

Michael Murphy; Oakleigh B. Thorne, the
Chairman of the Perennial Garden
Committee; and Bradley H. Roeller,
manager of the Arboretum’s display
gardens. During a champagne reception
following the ceremony, guests were
invited to tour the Garden with the
Arboretum’s horticultural staff, to learn
about its history as well as about the
numerous plantings.

The new Perennial Garden demonstrates
the relationship between good horticulture
and sound ecology. Knowledge of the

continued on page 4

Oakleigh Thorne, Gene Likens and Ann Loedy at the Perennial Garden dedication ceremonies.

When Animals Eat Rocks

Snails typically feed using teeth adapted
for scraping material off a surface. Snails
in the Negev Desert are proving to be not
at all typical, however, in that they eat
plants living beneath the surfaces of
rocks. Moreover, recent studies show
that this very unusual form of herbivory
is weathering the desert at a significant
rate.

Using a “snail simulator” - an electric
engraving tool - Dr. Moshe Shachak will scrape
away the top layer of a limestone rock. The
resulting material, identical to the material that
snails are eating, will be chemically analyzed by
Dr. Clive Jones (standing).

The Negev Desert Highlands in southern
Israel provides a harsh climate for its
few resident animals and plants. Rainfall
is slight --3.5 inches a year -- and seventy
percent of the area is covered with
limestone rocks. Each rock is a miniature
ecosystem: abiotic substrate (rock),
herbivores (snails) and a plant
community (lichens). Lichens are really
two organisms - an alga and a fungus --
in a symbiotic relationship. Epilithic
lichens live on the surface of a substrate
such as a rock or tree, while endolithic
lichens -- typical of harsh tundra, alpine
and dessert environments - live beneath
the rock surface. In this ecosystem the
snail eats endolithic lichens, and, while
doing so, has to eat the rock as well.
Eating rock is a form of biological
weathering, and, on the hillsides of the

Negev Desert, soils are produced more
rapidly by this means than by deposition
of wind-borne particles - one way in
which soils are typically formed.

Research on this tiny ecosystem began
when Dr. Moshe Shachak’, in col-
laboration with lES Chemical Ecologist
Dr. Clive Jones, observed two species of
the snail genus Euchondrus foraging on
limestone rocks in the Negev Desert.
These rocks were “home” to large
numbers of both epilithic and endolithic
lichens. Close examination of the
foraging areas showed trails - actual
gouges in the rock - apparently made by
the snails. The white color of the
exposed limestone indicated that the
lichens beneath the surface elsewhere in
the rock were gone from these feeding
areas. Chemical analysis showed that the
snails’ feces, which were also white, had
virtually the same calcium content as the
surface layer of rocks on which they
browsed (calcium carbonate is the major
component of limestone rocks).

Experimentation was done in the Negev
Desert, both in the field and in outdoor
enclosures, to determine the rate of rock
removal. Snails in the field, at densities
of less that one per rock, ate at a rate
which resulted in a disappearance of 4%
of the rock surface (to a depth of about 1
mm) over the course of a year. In the
enclosures the ecologists estimated that
7% of the rock surface was removed in a
year. Based on the estimates of the
annual grazing rates in the field and in
the enclosure, they calculated that the
snails were turning rock into soil at a rate
of approximately 1.89 to 3 tons per acre
each year.

Perhaps this figure can be brought closer
to home by picturing a snail at human
proportions. This giant snail - your
size! “ would need to eat something close
to 2.8 pounds of rock per meal to gain
sufficient nutrition from the resident
population of endolithic lichens.

It is an understatement to say that these
figures are impressive, but the best way
to test their significance is to compare
them with what was generally
considered to be the main source of soil
in the dessert: dust deposition from
wind. By measuring the total dust
deposition on stones in the same area as
the biological weathering was occurring,
Drs. Shachak and Jones estimated a rate
of approximately 0.98 tons per acre per
year, which is essentially one half to one

third of the rate at which the snails form
new soil by eating lichen and rock!

The Negev Desert snails are not lichen
gluttons. However, because lichens are
low in nutrient value, the snails must eat
a large amount of rock to find enough
plant material to survive. Observations in
this snail/lichen/rock ecosystem study
have demonstrated that herbivores --
even those that consume relatively small
amounts of plant material - can play a far
more significant role in the processes
occurring in an ecosystem than had been
thought previously.

Snails and their trails.

itfi il/t Hn

This research was reported in the May
29th issue of the prestigious scientific
journal, SCIENCE (Vol. 236, pp. 1098-
1099). The featured paper, by Moshe
Shachak, Clive Jones and Yigal Granot,
is entitled “Herbivory in Rocks and the
Weathering of a Desert”.

’ Dr. Shachak has visited the Institute of
Ecosytem Studies to collaborate on ecosystem
research three times since 1984, most
recently in September 1986. He is a senior
investigator at The Jacob Blaustein Institute
for Desert Research, Ben-Gurion University
of the Negev in Israel. Funding for Dr.
Shachak’s research at lES was provided by
the Mary Flagler Cary Charitable Trust

New Staff

CAROLE ANNE CORRADO,

research assistant I, is working for
Laboratory Manager John Eaton. A
graduate of the State University of New
York at Plattsburgh with a bachelor’s
degree in biology and chemistry, her
responsibilities at lES include the
inorganic analysis of Hubbard Brook
Ecosystem Study samples.

Shoemaker

Recognized

David R. Shoemaker, an lES summer
project assistant in 1985 and 1986, is the
recipient of the 1987 P.F. English
Memorial Award. This award is presented
annually by The Northeast Section, The
Wildlife Society, to the outstanding
undergraduate student of wildlife biology
or wildlife management in the region.

Mr. Shoemaker graduated in May from
Unity College in Maine with a bachelor of
science degree in wildlife ecology.
Throughout his college career he was
actively involved in a variety of research
projects, including Lyme tick and deer
repellent studies with lES wildlife
ecologists. He is beginning his Ph.D. work
this summer in the Cooperative Wildlife
Research Laboratory at Southern Illinois
University.

DAVID M. WOOD, postdoctoral
associate, is working with lES Plant
Ecologist Dr. Charles Canham. As the
Right-of-Way Project coordinator. Dr.
Wood supervises field experiments and
analyzes resulting data. Dr. Wood’s Ph.D.
research at the University of Washington
in Seattle dealt with primary succession in
high elevation habitats on Mount St.
Helens.

EDWARD A. ROY, left, is forest
manager at The New York Botanical
Garden in the Bronx. Supervised by lES
Terrestrial Ecologist Dr. Mark
McDonnell, Mr. Roy is responsible for
coordinating the scientific and
management activities in the NYBG
Forest. His current emphasis is trail
restoration and replacement of signs, and
coordination of activities at the Lucy
Moses Overlook. He also assists Dr.
McDonnell with studies of sixteen
permanent plots in the Forest. Mr. Roy
has a bachelor of science degree in botany
and plant pathology from the University of
New Hampshire.

lES Wildlife Ecologist Jay McAninch (left),
current president of The Northeast Section, The
Wildlife Society, and award recipient David
Shoemaker.

Mr. Shoemaker was honored at the
Northeast Fish and Wildlife Conference
banquet held on May 5th in Boston. The
purpose of the P.F. English Award is to
acknowledge and encourage exceptional
students, and to perpetuate the memory of
Dr. English, an outstanding educator in
the field of wildlife management.

Research Support

A gift of $100,000 has been received from
the charitable trust created by the will of
Mrs. Marilyn M. Simpson. This bequest
will support research being done by
Institute of Ecosystem Studies scientists.

The trustees’ decision was based on the
similarity between Mrs. Simpson’s
interests and those of the lES research
program. A resident of Katonah, New
York, Mrs. Simpson was very much at
home in the out-of-doors and was
especially interested in ecological and
environmental issues of the Hudson Valley
area.

Conference ...from page i

While ecologists themselves are aware of
the importance of these studies, there is
still a need for increased awareness by
public officials and others. Cary
Conference participants were asked to
consider the topic “Long-Term Studies in
Ecology; Approaches and Alternatives’’
The goal was to bring sustained ecological
research more to the forefront of current
scientific investigation.

At the final session. Dr. Likens introduced
a draft statement prepared by a group of
participants requesting a commitment to
sustained ecological research and a new
partnership between scientists and
resource managers ... groups with
common long-term goals. The conferees
gave the draft unanimous endorsement.

In his closing remarks. Dr. Likens stated
his pleasure at the decisions that were
reached and reemphasized the importance
of sustained ecological research. “The
collection of long-term data will help solve
some of our major environmental
problems on this planet; if we are unable to
solve these problems, the quality of life
will be reduced.’’ Pointing out that the
time is favorable now to promote and do
long-term ecological research, he urged
participants to “grasp these opportunities
and make them work to the betterment of
humankind!’’

i(< « « iK 111

The 1987 Cary Conference was the second
such meeting organized at the Institute of
Ecosystem Studies. In May 1985,
participants met to consider the “Status
and Future of Ecosystem Science”. These
conferences were supported by the Mary
Flagler Cary Charitable Trust and the
National Science Foundation. Proceedings
of the first conference are available in a
report just published by lES. Proceedings
of the second conference will be published
as a book edited by Dr. Likens.

Dedication ... from page 1

ecological principles of plant adaptation
and persistence is combined with the best
in horticultural design. The result: a model
of low-maintenance garden beauty,
appropriate for the Arboretum as home of
the Institute of Ecosystem Studies. The
garden boasts over 4500 plants
representing 800 different species and/or
cultivars, and is therefore one of the
largest collections of herbaceous
perennials to be seen in any public garden
in the northeastern United States.

Designed by Robert S. Hebb, former
Arboretum horticulturist, and Carlton B.
Lees, retired senior vice president of
horticulture at The New York Botanical
Garden, the garden was constructed by
Arboretum staff under Mr. Roeller’s
supervision. Support for the work was
provided by matching grants from the
Millbrook Tribute Garden, Inc. and the
McCann Foundation, as well as by
generous gifts from members of the local
community.

A special Perennial Garden brochure was
prepared by former lES intern Collin
Harty. This brochure, which includes a
map of the plantings, is free to all
Arboretum visitors to increase their
enjoyment of the garden. The garden is
open to the public during Arboretum
hours, with a free access permit from the
Gifford House.

Summer/Fall Calendar

COURSES

Fall Adult Education Program courses in landscape
design, gardening and botany will begin in mid-
September:

Landscape Design Theory
Graphics

Landscape Design III: Planting Design
Construction II: Site Detailing
Surveying for Landscape Design

Fundamentals of Gardening
Soil Science

Plant Propagation and Grafting
Commercial Greenhouse Management

Basic Botany

Special Workshops

Oct. 7th “ Airphoto Interpretation and Land Use:

An Introduction to Basic Techniques
Oct. 31st - Landscape Site Plans: Interpretation and
Review

Nov. 14th - Landscape Preservation: Ecological and
Social Issues

If you would like to receive a catalogue and are not
already on our mailing list, call the Gifford House at
the number below.

FALL ECOLOGICAL EXCURSIONS

Join us for one or more of the following day trips:

Estuarine Ecology: Canoe Exploration of
Constitution Marsh
Catskill Mountain Ecosystems
Hudson River Ecology Cruise on the Sloop
Clearwater

Agricultural Ecology of the Mid-Hudson Valley

For details and registration information, call the
number below.

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. (There will not be a
Sunday Program on the Labor Day weekend.)

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

Sept. 20th: Pond ecology ... another perspective
(Michael Pace) - Walk

Oct. 4th: How do old fields turn into forests?
(Steward Pickett) - Walk

Oct. 18th: The secret life of soils (Alan Berkowitz) -
Walk

Nov. 1st: Topic to be announced
Nov. 15th: Air pollution and the forest
(Gary Lovett) - Walk

For ecology walks, wear long pants and sturdy
footwear with socks; long-sleeved shirts or jackets are
also recommended. In case of inclement weather, call
(914) 677-5358 after 1 pm to learn the status of the
day’s program.

RESEARCH DISPLAYS

lES is setting up displays to introduce Arboretum
visitors to the methods and thinking behind ongoing
ecological research projects. The first of these to be
completed is "Acid Rain Study Ponds’’, behind the
Gifford House. Here, a series of tanks simulating
natural ponds (complete with plants and animals) are
exposed to different chemical treatments and the
results recorded twice a week. This free demon-
stration is open to the public during Arboretum hours
through October; children must be accompanied by an
adult. An lES staff scientist will give special programs
to groups that call the number below for an
appointment.

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 (see below).

SCIENTIFIC SEMINARS

The Institute’s weekly program of scientific seminars
will resume in September. This program 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. 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 enterprising
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 memberships, contact Janice
Claiborne at (914) 677-5343.

For more information, call (914) 677-5359 weekdays from 8:30 - 4:30.

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

Newsletter

Volume 4, Number 4
July - August 1987

Nonprofit Org.
U.S. Postage
PAID

Millbrook, N.Y.
Permit No. 16

100% Recycled
Paper