Newsletter

Volume 10, Number 5
September - October 1993

Director’s Note

Ten years ago we began an experiment.
With funds from the Mary Flagler Cary
Charitable Trust and administrative
freedom from The New York Botanical
Garden, I assembled a team of remarkable
scientists and support staff to build a small
ecological institute of excellence. This
experiment has gotten off to a superb start
and the Institute of Ecosystem Studies has
had many extraordinary successes.

As the Earth’s environmental systems
increasingly are assaulted at all levels, it is
vital that this experiment succeed.
Ecological understanding and education
offer tangible hope for addressing
multifaceted and potentially devastating
environmental problems. Unraveling
ecological complexity and communicating
the results to decision makers in a useful
way are monumental tasks. Now, facing
the future as a separate and independent
corporate institution, we at lES are excited
by our unique opportunities to address
these challenges.

The lES Newsletter is published by the
Institute of Ecosystem Studies, Millbrook,
New York. 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
Printing: Central Press

INSTITUTE OF ECOSYSTEM STUDIES
Education Program
Box R (Route 44 A)

Millbrook, NY 12545-0178
(914) 677-5359

Ten Years for lES, and a New Beginning

This is a proud and important time for the
Institute of Ecosystem Studies. First, it is
the Institute’s anniversary. Founded exactly
10 years ago as a division of The New York
Botanical Garden, lES is celebrating a
decade during which it has gained interna-
tional recognition for its research and
education programs in ecology and the
analysis of ecosystems.

A second milestone is the Institute’s new
independent status. Three years after the
death of Mary Flagler Cary, the trustees of
the charitable trust created under her will
deeded her property to The New York
Botanical Garden. The Mary Flagler Cary
Arboretum evolved subsequently as a
distinct program 75 miles distant from the
Garden’s Bronx headquarters. Financially
independent of the Garden from the outset,
the program gained new impetus with the
appointment of Dr. Gene E. Likens in 1983
to found the Institute of Ecosystem Studies.
The latest move to full independence simply
affirms the strength and maturity of this
leading center of research and education in
ecology.

While the new corporation was formed in
February 1993 and non-profit status granted
by the Internal Revenue Service in July,
November 1 officially marked the
Institute’s new beginning. The first meeting
of the new lES board of trustees was held in
mid-October. The Institute’s facilities, staff,
research and education programs and day-
to-day activities are not changing with
independence.

Dr. Likens is president of the new corpora-
tion while retaining the title of lES director.
The Institute’s board is chaired by Gretchen
Long Glickman. Millbrook resident
Oakleigh B. Thorne, who previously

chaired the committee of The New York
Botanical Garden that oversaw the program
of the Institute, is vice-chairman.

Institute of Ecosystem Studies
Board of Trustees
Mr. Edward A. Ames, Secretary
Trustee of the Mary Flagler Cary Charitable
Trust, New York, N.Y.

Mrs. John R.H. Blum

Member of the Sharon Hospital board of

trustees, Sharon, Conn.

Dr. Winslow R. Briggs
Faculty member at the Department of Plant
Biology, Carnegie Institution of Washing-
ton, Stanford, Calif.

Ms. Gretchen Long Glickman, Chairman
President of the Greater Yellowstone
Coalition and Vice-Chairman of Green
Seal, Inc., New York, N.Y
Mr. Thomas J. Hubbard
Chairman, The New York Botanical
Garden board of managers; attorney with
Decker, Hubbard & Welden, New York,
N.Y.

Dr. Gene E. Likens, President
Director of the Institute of Ecosystem
Studies, Millbrook, N.Y.

Dr. Thomas E. Lovejoy
Assistant Secretary for External Affairs at
the Smithsonian Institution, Washington,
D.C.

Dr. Paul G. Risser, Treasurer
President of Miami University, Oxford, Oh.

Mr. John E. Rorer

Executive Vice President of The New York
Botanical Garden, Bronx, N.Y.

Dr. Lee M. Talbot

Head of Lee Talbot Associates International
(advisors on the environmental dimensions
of international development), McLean, Va.
Mr. Oakleigh B. Thorne, Vice-Chairman
Chairman of the Board of CT Corporation
System (New York City), Millbrook, N.Y.

Ms. Gretchen Long Glickman, chairman, and Dr. Gene E. Likens, president, review material prior to
the first meeting of the lES board of trustees.

Summer 1993 at the Institute of Ecosystem Studies: Selected Highlights

Cary Summer Fellowships

The Cary Summer Fellowship is an annual
award enabling one or more scientists to
do research at the Institute. Funds for the
award are provided by the Mary Flagler
Cary Charitable Trust and provide Cary
Fellows with the opportunity to pursue
intensive studies, free from academic
responsibilities. The scientists’ work
contributes to and strengthens their
ongoing teaching and/or research pro-
grams at their home institutions. During
summer 1993, Cary Summer Fellowships
were awarded to Dr. Marie-Josee Fortin
and Dr. Erik Kiviat.

As a Cary Fellow, Dr. Fortin used data
from Dr. Canham’s long-term study of a
mixed hardwood forest in northwestern
Connecticut to develop a computer model
that adds a new dimension to the analysis of
forest gaps. Gaps, which are openings in
the forest canopy, allow increased amounts
of light (one of the three main resources,
with water and soil nitrogen, necessary for
plant growth) to reach the forest floor. In
this way they directly affect the develop-
ment of seedlings and saplings. The
computer model recently developed by Dr.
Fortin takes into consideration the spatial
variation of light levels within gaps and
predicts the changes that will occur in and
around gaps over time.

chosen and arrived at the Institute at the end
of May. Working with lES mentor scien-
tists, they conceived and designed their
investigations, did field and laboratory
research and prepared their findings for
presentation at a public symposium late in
August. Along the way they learned about
methods, applications and issues in science
during weekly “Research Strategies” and
“Research in Context” sessions led by
Institute scientists and guest lecturers.
During a mid-July “Forum on Opportuni-
ties in Ecology”, REU students as well as
students from local colleges and universities
learned about the pros and cons of careers
in science from 1 2 professionals represent-
ing research, academia, environmental
activism, protection and management, law,
industry, government and public education.

Above: Dr. Marie-Josee Fortin uses computer
Modeling forest change models to predict forest change.

Cary Summer Fellow Dr. Marie-Josee
Fortin spent two months collaborating with
lES plant ecologist Dr. Charles Canham on
his studies of forest dynamics. A post-
doctoral scientist at the Centre D’Etudes
Nordiques, Universite Laval, Quebec, Dr.
Fortin is a statistical ecologist whose focus
is on spatial statistics and landscape
ecology.

At Universite Laval, Dr. Fortin is doing the
statistical analyses for two major studies.
Working with Dr. Serge Payette, she is
investigating sugar maple decline by
comparing tree ring width with long-term
temperature and precipitation records at 16
sites in southern Quebec. Her second
project deals with the dynamics of natural
fires in the boreal forests and tundra in
northern Quebec. She is developing a
computer model that will relate historical
data, obtained from analyzing fire scars and
charcoal samples, to distribution of fire in
this century. Her model will help scientists
determine the key factors that lead to
deforestation in the tundra.

An article describing research by Dr.
Kiviat on Blanding’s turtles and their
habitats will appear in the next issue of the
newsletter.

Research Experiences for
Undergraduates Program

Fifty-four college undergraduates from
across the United States have experienced
the challenges and rewards of independent
scientific research, thanks to the Research
Experiences for Undergraduates (REU)
program at the Institute of Ecosystem
Studies. The Institute’s REU program,
funded by the National Science Foundation
(NSF), has been in place since summer
1988, and each year the task of selecting the
best-qualified students from among the
many applicants has' become more difficult.

Applications for this year’s program began
arriving in January, and at final count
numbered over 150. Eight students were

The 1993 REU students and their projects
were:

• Joel E. Brown (SUNY College of
Environmental Science and Forestry, N.Y.):
Comparative field studies between an
invasive exotic plant species, Lythrum
salicaria L. (purple loosestrife) and two
native plant species, Solidago spp.
(goldenrod) Eupatorium spp. (boneset)
in a mesic old field. Dr. S.T.A. Pickett,
mentor

• Susan Haddox (Gustavus Adolphus
College, Minn.): The effects of damage on
shoot elongation in Populus deltoides
(cottonwood). Dr. C.G. Jones, mentor.

• Jennifer A. McMahon (Baldwin-Wallace
College, Ohio): The spatial variation in
abundance and reproductive rates of
Bosmina longirostris in the Hudson River.
Dr. M.L. Pace, mentor.

• Keith A. Perchemlides (Bard College,
N.Y.): Vegetational controls on nitrogen
cycling in a Catskill Mountain watershed.
Drs. G.M. Lovett and K.C. Weathers,
mentors.

• Hudson A. Roditi (SUNY New Paltz,
N.Y.): The effects of zebra mussels
(Dreissena polymorpha) on phytoplankton
in the Hudson River. Dr. J.J. Cole, mentor.

• Jasper Steenhuis (Binghamton Univ.,
N.Y.): Patterns of DOC composition and
microbial assimilation in the hyporheic
zone: enzyme analysis. Dr. S.E.G. Findlay,
mentor.

• David A. Steinberg (Cornell Univ.,

N.Y.): The effects of earthworms on
nitrogen mineralization along an urban-
rural land use gradient. Dr. R.A. Pouyat,
mentor. [See following story]

• Carolyn P. Williams (Mississippi Valley
State Univ., Miss.): Patterns of DOC
composition and microbial assimilation in
the hyporheic zone: composition of
dissolved organic carbon. Dr. S.E.G.
Findlay, mentor.

The students’ findings will be published as
an lES Miscellaneous Publication.

The NSF initiated the REU program in the
1 980s to improve science education and to
help assure an adequate supply of top-notch
scientists, mathematicians and engineers for
the future. Many institutions across the
country compete for annual funding for this
program, and lES is proud of its success in
receiving REU grants for six consecutive
years.

REU Study:

Earthworms Make a Difference

REU student David Steinberg helped lES
visiting scientist Dr. Richard Pouyat (U.S.
Department of Agriculture Forest Service)
explore a paradox. In the course of his work
with the Institute’s long-term urban-to-rural
gradient ecosystem studies. Dr. Pouyat had
discovered that while the soils in rural areas
had higher quality leaf litter (more easily
broken down by decomposer organisms)
than did urban soils, the nitrogen mineral-
ization* rates in urban soils were higher.
Normally, in higher quality litter, organic
matter is broken down more quickly and
therefore nitrogen mineralization rates are
correspondingly high. What could explain
the disparity between leaf litter quality and
nitrogen mineralization rates along the
gradient? There may be several explana-
tions, and Mr. Steinberg investigated one
that may prove to be especially significant:

* Nitrogen mineralization is the process
by which organic nitrogen from dead
plants and animals is made available in
inorganic (mineral) form. This active
process is carried out by bacteria, fungi
and other decomposers.

earthworms.

It is hypothesized that all earthworms in
areas of North America that were covered
by glaciers died during the Pliocene epoch
1.6-5 million years ago. Most earthworms
in the U.S. Northeast today, then, were
introduced by European settlers — in soil
used as ballast, for example — over the last
few centuries. Human-modified environ-
ments, such as agricultural, urban and
suburban areas, suited these introduced
species well and they flourished.

Earthworms are scavengers; not only do
they eat rotting leaves and other plant
material, but as they tunnel they eat soil and
digest the tiny bits of organic matter that are
mixed in with particles of rocks and sand.
Their castings contain plant matter mixed
with soil, a mixture that assists decompos-
ers in the further breakdown of organic
material into its inorganic components. In
addition, the worms’ sub-surface tunnels
increase aeration and drainage of the soil.
Can these activities be responsible for the
high nitrogen mineralization rates found in
the urban soils? If so, then introducing
earthworms into rural soils should lead to
even higher mineralization rates since the
litter quality there is higher.

Mr. Steinberg first determined earthworm
density at sites in three areas along the
urban-rural gradient: Bronx, N.Y. (urban),
Westchester County, N.Y. (suburban), and
northwestern Connecticut (rural). He
recorded great variation, but in general
found a significantly higher number of
worms at the urban end of the gradient —
up to 5 1 per square meter, compared to 3 to
4 per square meter at the rural end.

He then attempted to establish
experimentally whether
earthworms can increase
nitrogen mineralization in both
urban and rural soils. He used
mason jars to create 24
microcosms, filling 12 with
urban soil and 12 with rural
soil, and adding earthworms to
six of each type. He determined
that while there was mineral-
ization in all four microcosms,
levels in those with earthworms
were higher with the greatest
response shown in rural soil.
These data, coupled with Mr.
Steinberg's earlier results on
earthworm densities, suggest
that earthworm activity is a
potential explanation for the
disparity between leaf litter
quality and nitrogen mineral-
ization rates along the gradient.

Dr. Pouyat, standing, assists REU student David Steinberg.

High School Student
Receives lES Fellowship

This past spring, Ms. Heather S. York was
named the first lES Summer Research
Fellow under a new Institute program
designed to give selected winners at the
Dutchess County Regional Science Fair an
opportunity to continue doing research. As
a junior at Roy C. Ketcham High School in
Wappingers Falls, N.Y., Ms. York won the
1993 grand prize at the regional fair with a
project on “The Effects of Acidity on
Hatching, Development and Survival of
Anurans*”. Ms. York was also the grand
prize winner in 1992 for her study of the
effects of salt on seed germination, and that
year Institute director Dr. Gene E. Likens
presented her with the lES Best Project in
Environmental Science and Ecology Award.

With laboratory space, equipment and a
stipend provided by the lES fellowship, Ms.
York was free to develop her own research
project. She became intrigued by the
possibility of biological control of the deer
tick, the arthropod that transmits Lyme
disease. After discussing the idea with lES
animal ecologist Dr. Richard S. Ostfeld,
who is studying the ecology of the deer tick,
and her primary mentor Dr. Josh Van
Buskirk, who is developing a computer
model for the ecology of Lyme disease, she
learned that no one knows why ticks are
found on some small mammals in greater
numbers than on others. Do ticks have a
preference? Why are the greatest numbers
of ticks found on the white-footed mouse?

Is it possible that the presence or absence of
ticks is a function of the mammals’
grooming behavior? Ms. York designed a
study to answer these questions.

She collected ticks by dragging a square of
white cloth through a section of forest; most
of the ticks she collected were in the larval
stage, common in mid- to late-summer. She
then did two experiments. First, using a
cage with two chambers, she put a meadow
vole on one side and a white-footed mouse
on the other. Ten ticks were placed between
them, and Tanglefoot® — a sticky material
— was spread on the floor of the enclosure.
Counting trapped ticks suggested that there
was no preference for either of the two
mammals; however, a parallel study using
an enclosure with one empty chamber
showed that at least ticks do recognize the
presence of an animal.

Ms. York’s second study was designed to
learn more about grooming behavior: do

continued on page 4

* Anura is an order in the Class Amphibia
that comprises frogs and toads.

student, from page 3

Heather York with vole for tick study.

“busy” mice and voles groom less than
mice and voles with nothing to do? She put
10 larval ticks on each of two animals, one
of which was in a cage equipped with
wheel, playing tubes and climbing equip-
ment while the other was in an identical
enclosure without toys. She videotaped
behavior for an hour during daylight and an
hour at night and after 24 hours counted the
ticks. When she analyzes her data, she
expects to find that mice and voles with less
to do groom more, and this may result in a
difference in the number of attached ticks.
She notes that voles groom more than mice
do, with special attention to their ears. The
ears of white-footed mice are where most
ticks are found.

Ms. York will be completing her data
analysis and writing up the project results
during her senior year in high school, then
looks forward to a career in biomedical
engineering or veterinary science.

INSTITUTE OF
ECOSYSTEM STUDIES
Education Program
Box R

Millbrook, New York 12545-0178

Newsletter

Volume 10, Number 5
September - October 1 993

Calendar

CONTINUING EDUCATION
The final offerings for the fall semester are:

Dec. 18: Holiday Crafts Classes:

Williamsburg Door Decoration
Fresh Holiday Centerpiece

The winter semester begins the week of January
17, 1994. Call the Gifford House at 914/677-5359
for a free catalogue describing classses, workshops
andexcursions.

SUNDAY ECOLOGY PROGRAMS
Free public programs are held on the first and
third Sunday of each month, except over holiday
weekends. Programs begin at 2 p.m. at the Gifford
House on Route 44A unless otherwise noted. Last-
minute schedule changes are sometimes unavoid-
able, so call 914/677-5359 to confirm the day’s
topic.

The January - July 1994 schedule has not been
finalized, but set aside Sunday, January 16 for the
first program of the new year. For information, call
the number above.

lES SEMINARS

The Institute’s program of scientific seminars
features presentations by visiting scientists. These
free seminars are held each Friday at 3:30 p.m. in
the Plant Science Building. Last-minute schedule
changes are sometimes unavoidable, so call 914/
677-5343 to confirm the day’s topic.

The final seminar for the 1 993 season is:

Dec. 10: Resolving Conflicts Between Needs
for Agricultural Production and Climate
Protection in the 21st Century, Dr. Robert
Harriss, Univ. of N.H.

The 1994 scientific seminar program begins on
Friday, January 14. For information, call the
seminar coordinator at 677-5343.

GREENHOUSE

The lES greenhouse is a year-round tropical plant
paradise as well as a site for controlled environmental
research. The greenhouse is open until 4:00 p.m.
daily except public holidays. Admission is by free
permit from the Gifford House.

GIFT SHOP

Senior Citizens Days: On Wednesdays, senior
citizens receive a 1 0% discount (except sale items).
January “Month-Long Sale”: All regularly priced
gifts discounted 20%, books discounted 1 0% and
most hoi iday items discounted 50%.

HOURS

(Winter hours: October 1 - April 30;
closed on public holidays)

Public attractions are open Mon. - Sat., 9 a.m. -
4 p.m.; Sun. 1 - 4 p.m.; trails and roadways are closed
during the deer hunt.

The Gift and Plant Shop is open Mon..- Sat.,

1 1a.m. - 4 p.m. and Sun. 1 - 4 p.m.

(Closed weekdays from 1 - 1:30 p.m.)
Christmas and New Years: Closed Friday &
Saturday Dec. 24 & 25, and Dec. 3 1 & Jan. 1 ; open
during regular hours on Sunday Dec. 26 and Jan. 2.
•All visitors must pick up a free permit at the
Gifford House Visitor and Education Center on
Route 44 A for access to lES public attractions.
Permits are available until 3:00 p.m. daily.

MEMBERSHIP

Become a member of the Institute of Ecosystem
Studies. Benefits include a member's rate for lES
courses and excursions, a 10% discount on Gift Shop
purchases, a free subscription to the lES Newsletter,
and participation in a reciprocal admissions program,
with benefits at over 1 00 nature centers, forest
preserves, gardens and conservatories in the U.S. and
Canada. Individual membership is $30; family
membership is $40. For information on memberships,
call Janice Claiborne at 914/ 677-5343.

For more information, call the lES Education Program Office at the Gifford House
Visitor and Education Center: 9141677-5359 weekdays from 8:30 - 4:30.

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