Atlantic White Cedar: Ecology, 

Restoration, and Management

Proceedings of the Arlington 

Echo Symposium

Millersville, Maryland

June 2–4, 2003

Southern 

Research Station

General Technical

Report SRS–91

United States

Department of

Agriculture

Forest Service
December 2005

Southern Research Station

P.O. Box 2680

Asheville, NC 28802

Cover photos: Aerial photos (1,000-foot altitude) of the Penn Swamp clearcut in Wharton State 

Forest, New Jersey, and the site of the subsequent deer-slash experiment: 1990 (top photo, as 

clearcut was being finished), 1995 (middle photo), and 2000 (bottom photo).

Photos and cover design by George Zimmermann.

DISCLAIMER

The use of trade or firm names in this publication is for reader information and does not imply endorsement of any product or 

service by the U.S. Department of Agriculture or other organizations represented here.

Papers were edited to a uniform format and type style; however, authors are responsible for the accuracy and content of their 

papers.

PESTICIDE PRECAUTIONARY STATEMENT

This publication reports research involving pesticides. It does not contain recommendations for their use, nor does it imply that 

the uses discussed here have been registered. All uses of pesticides must be registered by appropriate State and/or Federal 

agencies before they can be recommended.

CAUTION: Pesticides can be injurious to humans, domestic animals, desirable plants, and fish or other wildlife—if they are not 

handled or applied properly. Use all herbicides selectively and carefully. Follow recommended practices for the disposal of surplus 

pesticides and their containers.

Papers published in these proceedings were submitted by authors in electronic media. Some editing was done to ensure a 

consistent format. Authors are responsible for content and accuracy of their individual papers and the quality of illustrative 

materials.
Editors:

Marianne K. Burke, Research Ecologist

USDA Forest Service

Southern Research Station

Asheville, NC 28804

Philip Sheridan, Director

Meadowview Biological Research Station

Woodford, VA 22580

Sponsors:

Anne Arundel County, MD

Arlington Echo Outdoor Education Center, Millersville, MD

Meadowview Biological Research Station, Woodford, VA

Underwood and Associates, Annapolis, MD

U.S. Department of Agriculture, Forest Service,

Southern Research Station, Asheville, NC

Atlantic White Cedar: Ecology,

Restoration, and Management

Proceedings of the Arlington

Echo Symposium

Millersville, Maryland

June 2–4, 2003
ii

I am pleased to write this preface to the proceedings of the symposium on Atlantic white-cedar (AWC) held 

at the Arlington Echo Outdoor Education Center, Millersville, MD, in June 2003, chaired by Keith Underwood 

and Philip Sheridan. 

The theme of the symposium was “Uniting Forces for Action,” and it was clear that the attendees were indeed

united in their desire to study this globally threatened species, gain a more holistic view of the AWC ecosystem,

and cooperate to insure that the scientific work so ably done here and elsewhere translates into action to 

restore and responsibly manage AWC.

More than 15 papers and a number of posters were presented during the symposium, and the attendees 

were able to view AWC sites, including a number of restoration sites. I was very impressed by the State of 

Maryland’s use of educational facilities such as Arlington Echo. These facilities have been used to give 

Maryland’s citizens (especially the children who in turn have educated and motivated their parents) a sense 

of their connection to the environment and the need for their help and stewardship in restoring AWC. 

Symposium attendees from other States can take home valuable lessons about environmental education.

Participants in the symposium came from throughout the range of white cedar, from New England to the Gulf 

coast. There is no doubt that this species, extirpated in many areas, has captured the attention and scrutiny 

of many researchers and other highly motivated individuals.

This publication includes a representative subset of the papers presented at the symposium. Laderman and 

Domozych’s paper expands our knowledge of other life forms inhabiting AWC habitats—a fundamental step 

in understanding the ecosystem as a whole. Papers by Crawford and others, Derby and Hinesley, Mylecraine 

and others, Hopton and Pederson, and Gengarelly and Lee give us more data on the physical aspects of 

white-cedar ecosystems and in some instances their interaction with the biological factors. These papers 

present information that will help us restore and understand AWC and their functioning.

The range, restoration, and stewardship of AWC ecosystems are discussed in papers by McCoy and Keeland,

Underwood and others, and Broersma-Cole. We also present the first of numerous papers by Mylecraine and

others that have given us vital information on range-wide AWC genetics, and finally a paper by Zimmermann

and Mylecraine that discusses the long-term effects of various silvicultural manipulations on the entire 

vegetation community. 

I hope that all of the papers and posters presented at the symposium will eventually find their way into the 

literature; they all contained information important to our understanding of the species, its continued 

restoration, and wise management across its range.

 George Zimmermann

 Professor of Environmental Studies

 Richard Stockton College of New Jersey

Preface
iii

Contents

Page

Chamaecyparis Thyoides (Atlantic White Cedar) 

Wetlands of Cape Cod, Massachusetts, USA: 

A Desmid Diversity Database . . . . . . . . . . . . . . . . . . . 1

Aimlee D. Laderman and David S. Domozych

Performance of Atlantic White-Cedar Plantings 

along Water Table Gradients at Two Sites in the 

New Jersey Pinelands . . . . . . . . . . . . . . . . . . . . . . . . . 7

Kristin A. Mylecraine, George L. Zimmermann,

 and John E. Kuser

Decomposition Dynamics in an Atlantic White 

Cedar Restoration Site. . . . . . . . . . . . . . . . . . . . . . . . . 11

Edward R. Crawford, Frank P. Day, and 

 Robert B. Atkinson

Water Table and Temperature Regime Affect 

Growth of Potted Atlantic White Cedar. . . . . . . . . . . . 17

Scott A. Derby and L. Eric Hinesley

Climate Sensitivity of Atlantic White Cedar at its 

Northern Range Limit. . . . . . . . . . . . . . . . . . . . . . . . . . 22

H. Myvonwynn Hopton and Neil Pederson

Distribution of Atlantic White-Cedar Seedlings in 

a New Hampshire Swamp: Association with 

Microsite Characteristics. . . . . . . . . . . . . . . . . . . . . . . 31

Lara M. Gengarelly and Thomas D. Lee

Page

Geographic Variation in Atlantic White-Cedar: 

Preliminary Provenance Results. . . . . . . . . . . . . . . . . 38

Kristin A. Mylecraine, John E. Kuser,

George L. Zimmermann, and Peter E. Smouse

Locations of Atlantic White Cedar in the Coastal 

Zone of Mississippi . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

John W. McCoy and Bobby D. Keeland

Atlantic White Cedar Species Recovery and

Wetland Enhancement Project at Howard’s Branch,

Anne Arundel County, Maryland . . . . . . . . . . . . . . . . . 54

Keith R. Underwood, William B. Moulden,

Dennis C. McMonigle and David J. Wallace

Regulation and Protection of Peatlands in

Anne Arundel County, Maryland . . . . . . . . . . . . . . . . . 62

Judy Broersma-Cole

Atlantic White-Cedar Regeneration and Vegetation 

Dynamics at Penn Swamp, New Jersey: 

Ten Years of Change. . . . . . . . . . . . . . . . . . . . . . . . . . . 65

 George L. Zimmermann and Kristin A. Mylecraine

Conference Attendees (Photograph) . . . . . . . . . . . . . 73

Author Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
iv
1

INTRODUCTION

The higher flora of acidic wetland forests dominated by 

Atlantic white cedar [Chamaecyparis thyoides (L.) BSP.] (AWC)

have a well-defined taxonomic skewing: they contain many 

species and genera in a few families, but there is a startling 

absence of the most common plants found in surrounding 

areas (Laderman 1987, 1989). Little is recorded of the algae

of AWC swamps: Hannah Croasdale (1935) included cedar

bog sites in “The Freshwater Algae of Woods Hole”; Drouet

and Cohen (1935, 1937) studied Gonyostomum in a Falmouth,

MA, cedar swamp; some New Jersey Pine Barrens algae 

were described by Moul and Buell (1979). An unpublished 

survey of herbarium and literature records included cedarassociated algae (Lloyd and others 1980), and Laderman 

(1980, 1987) reported on the periphytic and planktonic 

microflora of a Falmouth, MA, bog.

Cedar forests are disappearing in our own time in regions 

where they were once plentiful. Their historic distribution is 

indicated in figure 1a. Some go rapidly, replaced by shopping 

malls, commercial cranberry beds or scenic ponds. Others 

go slowly, swamped by an abundance of nutrients that favor 

cedar’s competitors. To reverse this trend of habitat loss and 

to restore Chamaecyparis forests, it is essential to improve 

our understanding of what makes for a healthy cedar swamp. 

By determining the composition of the producers of the associated microscopic community, we hope to gain insights into 

what makes AWC communities unique and what allows them 

to thrive.

Figure 2 summarizes the rigorous environmental factors 

that are known to affect AWC and other coastally restricted 

forests and act to exclude most other biota found in similar 

latitudes (Laderman 1998). The adaptive properties of the 

dominant trees of coastally restricted forests may have parallels in the microbiota.

These factors have been discussed in detail elsewhere 

(Laderman 1998, 2000). Figure 3 indicates proposed interrelationships of the physical, chemical and biological properties 

specific to C. thyoides wetland waters that select for extremophiles. Shallow, acid, poorly aerated waters, rich in organic 

acids and decayed organic matter—all characteristics of 

cedar bogs—are favorable habitat for an abundance of the 

green algal species known as desmids. Many desmids are 

found only in acid bogs, and figure 4 illustrates a few of these 

saccoderm and placoderm desmids.

This article is a report on the preparation of a database and 

Website of microscopic diversity in cedar wetlands using the 

desmid flora of seven Cape Cod bogs as prototype.

Goals of the entire project are: 

• To facilitate and stimulate further biodiversity, ecological, 

genetic and restoration work over the entire range of the 

keystone canopy dominant, C. thyoides, in all its diverse 

ecotypes 

• To lay the groundwork for coordination and support of 

research and restoration in AWC wetlands. The algae 

project is part two of an all-taxon rangewide survey of 

Atlantic white cedar wetlands. Part one, inventory of the 

higher flora, is now published (Laderman and Ward 1987, 

1989) and online http://gosnold.mbl.edu/awc/awcflora.

• To make this information widely available to the scientific 

community and to the public at large

CHAMAECYPARIS THYOIDES (ATLANTIC WHITE CEDAR)

WETLANDS OF CAPE COD, MASSACHUSETTS, USA:

A DESMID DIVERSITY DATABASE

Aimlee D. Laderman and David S. Domozych1

1 Aimlee D. Laderman, Director, Swamp Research Center, Marine Biological Laboratory, Woods Hole, MA 02543; and David S. Domozych, 

Professor, Chairman, Skidmore College, Department of Biology, Saratoga Springs, NY 12866.

Citation for proceedings: Burke, Marianne, K.; Sheridan, Philip, eds. 2005. Atlantic white cedar: ecology, restoration, and management: 

Proceedings of the Arlington Echo symposium. Gen. Tech. Rep. SRS-91. Asheville, NC: U.S. Department of Agriculture, Forest Service, 

Southern Research Station. 74 p.

Abstract—We are developing a database documenting the microscopic biodiversity of all Atlantic white cedar (AWC) 

[Chamaecyparis thyoides (L.) BSP.] wetland forests. A census of the desmid algal species of seven Cape Cod, MA AWC bogs

serves as prototype for the database. Desmids are microscopic unicellular or filamentous green algae (phylum Chlorophyta) 

in the order Zygnematales, families Mesotaeniaceae (saccoderms) and Desmidiaceae (placoderms). Over one dozen wetland

specialists in the AWC biodiversity network contributed Cape Cod samples. Field material is sorted, cultured, photographed 

or drawn, and preserved. Data is fed into two systems: (1) an all-taxon AWC rangewide biodiversity database and Website, 

and (2) an all-protist global database “micro*scope”. This report describes the first system. Information including images, 

genus, species, common names, family, and source is entered in a working Filemaker database and converted to Sequel 

Server format for interactive Web use. The completed database aims to document biodiversity of all taxa in all AWC wetlands 

across their entire range.

Keywords: Algae, Cape Cod, desmids, diversity, Massachusetts.
2

The objectives of the work reported here are:

• To catalog biodiversity of the desmid algae of Atlantic 

white cedar wetlands

• To analyze their taxonomic distribution

• To define a cadre of indicator species that would reflect the 

health of an AWC wetland

• To add to the global record of the distribution of microflora

The overall algae project has three major components: (1) 

field collection and morphological identification of algal flora: 

water, sediment, submerged vegetation and detritus are 

collected by a multidisciplinary network of colleagues (the 

Atlantic White Cedar Network [AWCnet] in AWC sites from 

Maine to Mississippi, and biogeochemical, ecological and 

geographic (GIS and USGS quad) data are gathered for 

each site, (2) archive of ecosystem collections in herbaria at 

Peabody (Yale University), Smithsonian (Washington, DC) 

and Gray Museum (Marine Biological Laboratory/Woods 

Hole Oceanographic Institution, Woods Hole, MA): dried 

unsorted samples from each site are prepared for ecosystem 

collections, (3) development of a Website for an interactive 

database: information for each species and site is stored 

in an electronic relational database designed to be part of 

global biodiversity records. The data will be accessible to the 

scientific community at the herbaria and via a searchable 

(databased) Website maintained at the Marine Biological 

Laboratory, Woods Hole, MA.

This report is restricted to the desmids of seven Cape Cod 

sites, indicated on the Cape Cod map in figure 1b.

PROCEDURES

The AWC biodiversity network specialists (AWCnet) collect 

water, moss, and detritus from cedar wetlands. After sorting, 

algae are cultured, photographed, preserved, identified, and 

this information is entered in a database that is imported 

into a Website linked to a global database. The AWCnet is 

composed of over three dozen limnologists, hydrologists, 

foresters, botanists and mosquito control and soils specialists in Government and private agencies covering the East 

Coast of the United States. 

Field Collection

When possible, all samples are taken from water or saturated

areas where cedar trees are the dominant or sole canopy 

occupant; sampling is done as close to the trees as is practical. The richest harvest is usually found in the photic zone 

associated with solid substrate, e.g., moss, especially 

Sphagnum; bits of detritus; cedar bark. Water levels in cedar

swamps vary from year to year and with the seasons, precipitation, drawdowns from sources outside the swamp but with

a contiguous water table, and tree harvest. Many algae are

found even when surface water is absent. When water is 

present, the surface skim is collected. Fresh material is transported in simple plastic snap-tight or zippered bags, kept cool

as possible, and hand delivered or shipped to the laboratory 

in refrigerated insulated containers by overnight mail. Moss, 

cedar bark, and bits of other submerged or emergent plant

material, folded securely into an unsealed paper envelope 

and allowed to dry, yield excellent specimens. Dry material is 

not as sensitive to temperature and light variation and may 

be shipped by regular mail. Procedures may vary as field 

conditions dictate.

Figure 1a—Map of Chamaecyparis 

thyoides distribution. Counties in which 

AWC has been found are inked in black. 

Compiled from field observations, herbaria, 

published material and personal communications (adapted from Laderman 1989).

Figure 1b—Map of Cape Cod, Massachusetts, USA, indicating collection 

sites. 
3

Figure 2—Cartoon illustrates the rigorous nature of the cedar forest environment that selects for extremophiles and related adaptive 

features of Chamaecyparis species (adapted from Laderman 2000).
4

Figure 4—Photomicrographs of living desmids found in Cape Cod AWC wetlands. These 

algae contain bright green chloroplasts. Magnification 250x-500x. a. Closterium

b. Micrasterias c. Cosmarium d. Tetmemorus.

Figure 3—Cedar wetland dynamics. Flow diagram indicates 

proposed interrelationships of the stringent physical, 

chemical and biological properties of AWC wetland waters 

(from Laderman 1989). *CEC = Cation Exchange Capacity.

Processing, Recording, and Data Transfer

It is preferable to study living algae, but portions of each 

collection are also preserved in three ways: in Lugol’s solution (an iodine-based algal preservative), in 70 percent 

ethanol, and dried in standard herbarium fashion. Samples 

are cultured (Baylson and others 2001) in three different 

media: (a) Woods Hole medium, (b) Waris medium, and 

(c) Desmid medium (Nichols 1973). Media (a) and (b) are 

supplemented with soil extract. 

The photomicrography systems we use are: (a) an Olympus 

BX60 microscope equipped with Nomarski differential interference contrast (DIC), fluorescence and phase optics; Optronics

Magnafire CCD camera, images captured using a Dell computer equipped with Image ProPlus software, and (b) an 

Olympus CK40 inverted culture microscope equipped with 

phase optics; Nikon Coolpix 995 digital camera, images 

captured using Dell computer equipped with Adobe®

Photoshop software.

Data for each photograph is maintained in a Microsoft® Excel

file recording the specimen’s identity, date and site of origin, 

collector, location of relevant notes in the laboratory notebook, and photographic details. Records are entered in a 

Filemaker Pro searchable database containing taxonomic 

(family, genus, species), site and collection data. These data 

are being imported into an illustrated interactive Website 

http://gosnold.mbl.edu/AWC/AWCalgae now under construction using SequelServer. Our data are also being entered 
5

into the queryable illustrated protistan global database 

“micro*scope” http://www.mbl.edu/microscope, which has a 

separate Atlantic white cedar wetland section. Thus information on cedar wetland microflora will soon be available worldwide online. 

Taxonomy, Reproduction, Morphology 

Desmids are classed in two families of the Order Zygnematales: Mesotaeniaceae (commonly: saccoderms) with no 

median constriction, and Desmidiaciae (placoderms) with a 

midline constriction dividing the cell into identical halves. A 

distinctive aspect of the life cycle is that there is a complete 

lack of flagellate stages. The Order Zygnematales usually have

amoeboid reproductive cells that fuse within a conjugation 

tube or gelatinous matrix. They also reproduce by simple cell 

division or with special structures (akinetes or aplanospores). 

The vegetative cells may be single or arranged in a simple 

filament. They may be planktonic, or as epiphytes, attached 

to submerged or emergent vegetation or debris. This order 

is found only in fresh water (Bold and Wynne 1978, PickettHeaps 1975, Whitford and Schumacher 1973).

OBSERVATIONS

Of the 63 algal species identified in Cape Cod AWC wetlands 

to date, 22 are desmids (table 1). All these desmids but one,

Netrium digitus, are in the family Desmidiaceae (placoderms).

The 21 placoderms are members of 11 genera. One genus, 

Staurastrum, is represented by 5 forms in 4 species, with one

Table 1—Desmid Algae of Cape Cod, Massachusetts

Chlorophyta (Green Algae)

Class Chlorophyceae

 Order Zygnematales (Conjugales)

 Family Mesotaeniaceae (Saccoderm desmids)

 Netrium digitus

 Family Desmidiaceae (Placoderm desmids)

 Pleurotaenium subcoronulatum v. detum

 Closterium sp. 1

 Closterium sp. 2

 Tetmemorus laevis

 Euastrum sp.

 Micrasterias truncata

 Cosmarium margaritatum

 C. pachydermum

 C. raciborskii

 C. trilobulatum v. depressum

 Xanthidium antilopaeum v. laeve

 X. cristatum v. uncinatum

 Staurastrum cingulum v. floridense

 S. dickiei v. maximum

 S. dickiei v. duospinum

 S. gracile

 S. quadrispinatum v. spicatum f. furcatum

 Hyalotheca dissiliens

 Desmidium swartzii

 Desmidium sp.

 Spondylosium pulchellum

Organization generally follows Whitford and Schumacher (1973)

Supplementary sources: Bourrelly (1966) and Prescott (1978)

species, S. dickiei, found in two forms. One genus, Cosmarium,

is represented by 4 species. Three genera—Closterium, 

Desmidium, and Xanthidium—are represented by 3 species 

each, and 6 genera—Euastrum, Hyalotheca, Micrasterias, 

Pleurotaenium, Spondylosium, and Tetmemorus—are each 

represented by a single species.

CONCLUSIONS

This preliminary evidence indicates that compared to other 

algal families, the desmids exhibit high species abundance in 

the cedar wetlands with very uneven taxonomic distribution 

(Laderman 1980, 1987). These observations are consistent

with previous findings that the desmids form part of a characteristic taxocene favoring undisturbed Sphagnum-carpeted 

cedar swamps (Croasdale 1935, Laderman 1987) and unpublished observations (Smith 1950). Of the 12 families found in 

our collections to date (unpublished laboratory notes), only 

those in the order Zygnematales are represented by more 

than one genus. Species and subtaxa are very unevenly 

distributed among the 11 placoderm genera, with 5 forms 

clustered in Staurastrum alone. This skewed diversity pattern 

is similar to that of cedar-associated tracheophytes, with 

the great majority of plant species clustered in one family, 

Ericaceae, commonly known as heaths (Laderman and Ward 

1987, 1989). Phyletic skewing reflects the rigorous conditions 

of the ecological-island bog forests. Here most species that 

are common in surrounding moderate sites cannot survive, 

and adaptive extremophilic genotypes appear to have radiated rapidly in the cedar bogs’ available although restrictive 

niches. Genetic analysis will be required to indicate patterns 

of evolution by revealing the true relationships of genera, 

species, and lower taxonomic forms.

Two morphological features may contribute to the desmids’ 

capacity to thrive and speciate so richly in the inhospitable 

cedar wetlands: (1) they often form tough, resistant zygotes 

that remain dormant in adverse conditions (Pickett-Heaps 

1975) and (2) vegetative forms characteristically produce a 

thick mucilage coating (Boney 1981; Gerrath 1993, 2003).

The labor-intensive process of collecting, identifying, and 

documenting the existence of the extremophilic microinhabitants of the cedar wetlands has just begun. The groundwork 

is now in place for expansion of the database to other algal 

taxa, and to cedar sites from Maine to Mississippi. We hope 

that the Website will facilitate not only research, but stewardship and conservation of the freshwater forests dominated by 

Chamaecyparis thyoides.

ACKNOWLEDGMENTS

Those who worked with the authors as contributors to the 

Cape Cod microflora to date are Jennifer Bowen, Jennifer 

Courcy, Rachel L. Donnette, Lael S. Laderman, David 

Patterson, Jonathan Polloni, Pamela Polloni, Gabrielle 

Sakolsky, Donald Schall, and field workers of Cape Cod 

Mosquito Control. Jessica Tallman, Marjorie Parmenter, and

Suzanne Donovan provided valuable technical assistance. 

Micro*scope is designed and maintained by David Patterson 

in Melbourne, Australia and the Bay Paul Center, Marine 

Biological Laboratory, Woods Hole, MA. This paper was 

greatly improved by comments of the reviewers of this 

volume. 
6

LITERATURE CITED

Baylson, F.A.; Stevens, B.W.; Domozych, D.S. 2001. Composition 

and synthesis of the pectin and protein components of the cell wall 

of Closterium acerosum (Chlorophyta). Journal of Phycology. 37: 

796-809.

Bold, H.C.; Wynne, M.J. 1978. Introduction to the algae. Englewood 

Cliffs, NJ: Prentice-Hall. 706 p.

Boney, A.D. 1981. Mucilage: the ubiquitous algal attribute. British 

Phycological Journal. 16: 115-132.

Bourrelly, P. 1966. Les algues d’eau douce: Algues vertes. Paris: 

Boubee and Cie.

Croasdale, H.T. 1935. The fresh water algae of Woods Hole, 

Massachusetts. Philadelphia, PA: University of Pennsylvania. 

134 p. Ph.D. thesis.

Drouet, F.; Cohen, A. 1935. The morphology of Gonyostomum 

semen from Woods Hole, Massachusetts. Biol. Bull. 68: 422-439.

Drouet, F.; Cohen, A. 1937. Further observations on Gonyostomum 

semen. Botanical Gazette. 98: 617-618.

Gerrath, J.F. 1993. The biology of desmids: a decade of progress. 

Progress in Phycological Research. 9: 79-192.

Gerrath, J.F. 2003. Conjugating green algae and desmids. In: Wehr, 

J.D.; Sheath, R.G., eds. Freshwater algae of North America: 

ecology and classification. New York: Academic Press: 353-381.

Laderman, A.D. 1980. Algal ecology of a Chamaecyparis thyoides

bog: an in situ microcosm study. Vestal, NY: Binghamton 

University. State University of New York. Ph.D. Dissertation.

Laderman, A.D., ed. 1987. Atlantic white cedar wetlands. Boulder, 

CO: Westview Press. 401 p.

Laderman, A.D. 1989. The ecology of the Atlantic white cedar 

wetlands: a community profile. U.S. Fish and Wildlife Service. 

Biological Report 85(7.21). 114 p.

Laderman, A.D. 1998. Freshwater forests of continental margins: 

overview and synthesis. In: Laderman, A.D., ed. Coastally 

restricted forests. New York: Oxford University Press: 3-35.

Laderman, A.D. 2000. Why does the freshwater genus Chamaecyparis

hug marine coasts? In: Atkinson, R.B.; Belcher, R.T.; Brown, D.A.; 

Perry, J.E., eds. Atlantic white cedar restoration ecology and 

managemant: Proceedings of a Symposium. Newport News, VA: 

Christopher Newport University: 1-30.

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Chamaecyparis thyoides: a checklist with common synonyms. In: 

Laderman, A.D., ed. Atlantic white cedar wetlands. Boulder, CO: 

Westview Press: 385-397.

Laderman, A.D.; Ward, D.B. 1989. Flora associated with 

Chamaecyparis thyoides: a distribution checklist. In: Laderman, 

A.D., ed. The ecology of Atlantic white cedar wetlands: a 

community profile. U.S. Fish and Wildlife Service Biological Report 

85(7.21): 91-107.

Lloyd, T.; Hastings, R.W.; White-Reimer, J. [and others]. 1980. 

Aquatic ecology of the New Jersey pinelands. Unpublished report 

prepared for the New Jersey Pinelands Commission. Philadelphia, 

PA: T. Lloyd Associates.

Moul, E.T.; Buell, H.F. 1979. Algae of the Pine Barrens. In: Forman, 

R.T.T., ed. New York: Pine Barrens: Ecosystems and Landscape. 

Academic Press: 425-440.

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Handbook of phycological methods. New York: Cambridge 

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 ed. 

New York, Toronto, London: McGraw Hill. 719 p.

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algae. Raleigh, NC: Sparks Press. 324 p.
7

INTRODUCTION

Atlantic white-cedar (AWC) [Chamaecyparis thyoides (L.) 

BSP.] is an obligate wetland tree species (Reed 1988), and is 

restricted to freshwater wetlands along the Atlantic and Gulf 

coasts of the United States. Its wood is durable, light weight, 

aromatic, and usually has an even, straight grain, and has 

been used for a wide variety of timber products (Korstian and

Brush 1931, Little 1950, Ward 1989). AWC ecosystems may 

also provide many ecological benefits including habitat for 

several plant and animal species, maintenance of water 

quality, and stabilization of stream flows. Over the past two

centuries, there has been a significant decline in the area

occupied by AWC in New Jersey (Mylecraine and Zimmermann 2003), as well as throughout its range (Frost 1987, 

Kuser and Zimmermann 1995). As a result, much recent 

interest has focused on the species, its management, and 

restoration. 

The occurrence of AWC wetlands may be limited by unfavorable moisture conditions (Little 1950). Further, inadequate 

hydrologic conditions may be detrimental to AWC regeneration, restoration and growth (Akerman 1923, Harshberger 

1916, Little 1950, Pinchot 1899, Zimmermann 1997), and 

must be considered when choosing sites for these activities. 

Recent greenhouse (Allison and Ehrenfeld 1999) and field 

(Harrison and others 2003, Mylecraine and others 2003) 

studies have begun to quantify the effects of hydrologic variables on AWC regeneration, and have found that both survival 

and growth of plantings are influenced by water table depth. 

This study focused on two highly disturbed, groundwater 

discharge wetlands in the New Jersey Pinelands. Because of 

the nature of these sites, many confounding factors could be 

eliminated allowing us to focus on hydrologic variables. The 

specific objective was to examine the survival and growth of

AWC plantings in relationship to water table depth. Preliminary, first season results of this study have been published 

(Mylecraine and others 2003). However, hydrologic conditions

vary both seasonally and annually, and long-term studies 

will be necessary to address these issues. Here we present 

results after two growing seasons. 

METHODS

Site Descriptions

Two sites were chosen within the Clayton Sand company 

property, located in Jackson Township, Ocean County, New 

Jersey (40° 4' N, 74° 23' W). Both sites were groundwater 

discharge wetlands with significant elevational and water 

table gradients over relatively short distances. Site 1 was 

highly disturbed, lacked vegetative cover, and was located 

adjacent to a current mining operation on a sterile, sandy 

soil. Site 2 was also highly disturbed, has previously been 

used for cranberry production, and had a steep slope leading 

to a small pond. Detailed site descriptions were previously 

described by Mylecraine and others (2003).

Experimental Design

AWC stecklings (rooted cuttings) were planted in fall, 1998, 

along the water table gradients at each site. At site 1, 366 

stecklings were planted in 16 rows. At site 2, 125 stecklings 

were planted in 5 rows. For both sites, stecklings in each row 

represented replicates at the same position along the water 

table gradient. Steckling survival and height growth were 

monitored through two growing seasons.

Water table depth was monitored across each site with a 

series of test wells. Each well was made from PVC piping, 

1.5 m in length and 2.5 cm in diameter. There were 36 wells 

at site 1 and 14 wells at site 2. 

PERFORMANCE OF ATLANTIC WHITE-CEDAR PLANTINGS ALONG

WATER TABLE GRADIENTS AT TWO SITES IN THE NEW JERSEY PINELANDS

Kristin A. Mylecraine, George L. Zimmermann, and John E. Kuser1

1 Kristin A. Mylecraine, Postdoctoral Researcher, Ohio State University, Department of Evolution, Ecology and Organismal Biology, Columbus, 

OH 43210; George L. Zimmermann, Professor, The Richard Stockton College of New Jersey, Division of Natural Sciences and Mathematics, 

Pomona, NJ 08240; and John E. Kuser, Professor Emeritus, Rutgers, The State University of New Jersey, Department of Ecology, Evolution and 

Natural Resources, New Brunswick, NJ 08901.

Citation for proceedings: Burke, Marianne, K.; Sheridan, Philip, eds. 2005. Atlantic white cedar: ecology, restoration, and management: 

Proceedings of the Arlington Echo symposium. Gen. Tech. Rep. SRS-91. Asheville, NC: U.S. Department of Agriculture, Forest Service, 

Southern Research Station. 74 p.

Abstract—This study examines the effect of water table depth on Atlantic white-cedar (AWC) [Chamaecyparis thyoides (L.) 

B.S.P.] plantings at two sites in the New Jersey Pinelands. In 1998, rooted cuttings were planted in successive rows along 

water table gradients, and survival and growth were monitored through two growing seasons. At site 1, there were significant 

differences in height growth across rows (representing different water table depths), but no significant differences in survival, 

although there was a trend toward increased mortality at greater water table depths. At site 2, there were significant differences in survival, but not height growth, across rows. Drought conditions in 1999 decreased survival at higher elevations. 

Slightly higher water tables during 2000 led to significant mortality at lower elevations probably due to long periods of inundation. These results should be considered when choosing sites for future AWC restoration projects. 

Keywords: Chamaecyparis thyoides, Cupressaceae, moisture requirement, water table, wetland. 
8

Relative elevations were measured for all rows of stecklings 

and test wells, using an optical transit. Three elevations were

taken and averaged to calculate the elevation for each steckling row. Test well data were used to establish the relationships

between elevation and mean water table depth at each site. 

These relationships were then used with the row elevations 

to calculate the mean water table depths for each row of 

AWC plantings (Mylecraine and others 2003).

All data analyses were conducted using SAS (SAS Institute), 

and each site was analyzed independently. Chi-square 

analyses were employed to test for significant differences 

in survival across rows. Additionally, repeated measures 

analysis of variance was carried out on steckling height, to 

test for significant variation in the height response through 

time, across rows.

RESULTS

Site 1

Both annual and seasonal variation in water table depth was 

observed throughout the study period. Mean water table 

depths, by row, are presented in table 1. Average values are 

presented for the entire monitoring period (1996–2000), as 

well as for each of the two years included in the current study 

(1999 and 2000). Averaged across all years (1996–2000), 

water table depths ranged from -21 cm (row 1) to -141 cm 

(row 16). Due to drought conditions during 1999, mean 

values were slightly lower than the 5-year average, while 

values during 2000 were close to the 5-year average. For 

both years, mean values during the growing season were 

only slightly lower than the yearly average (table 1). 

There were no significant differences in steckling survival 

across rows, representing different water table depths, 

although there was a trend toward decreased survival at 

greater water table depths. Percent survival through the first 

two growing seasons, by row, ranged from 72 to 100 percent 

(table 2). The row with the greatest water table depth (row 

16) also had the lowest survival—72 percent.

There was a significant time*row interaction for steckling 

height (fig. 1) p < 0.0001 suggesting significant variation in 

performance across rows over time. Mean growth, by row, 

ranged from 0.2 cm to 4.7 cm in 1999, and from 0.3 to 4.1 

cm in 2000 (table 2). Stecklings in rows 1 through 4 exhibited 

the greatest growth rates. In 1999, mean water tables for 

these rows ranged from -26 to -37 cm, with a maximum of 

4 cm and a minimum of -55. In 2000, mean water tables for 

Table 1—Mean water table depths (cm) through study

period at Site 1, by row. Overall mean includes all data

throughout the year, while growing season mean includes

all measurements between April and September

Overall Growing season

 1996-

Row 2000 1999 2000 1999 2000

 1 -21 -26 -22 -27 -22

 2 -26 -31 -27 -32 -27

 3 -25 -29 -25 -31 -26

 4 -32 -37 -33 -38 -33

 5 -40 -44 -40 -46 -41

 6 -42 -46 -42 -48 -43

 7 -49 -53 -49 -54 -50

 8 -53 -57 -53 -58 -53

 9 -57 -61 -57 -62 -57

10 -62 -65 -61 -66 -62

11 -67 -70 -66 -71 -66

12 -72 -76 -72 -77 -73

13 -78 -82 -78 -83 -79

14 -84 -88 -84 -89 -84

15 -97 -101 -97 -102 -97

16 -141 -144 -140 -144 -140

Table 2—Survival and growth of AWC stecklings planted 

at Site 1, by row. Standard errors are in parentheses

 % Survival Height Growth (cm) 

Row N 1999 2000 1999 2000

 1 24 100 100 4.7 (0.7) 4.1 (0.3)

 2 23 91 91 5.0 (0.6) 4.1 (0.5)

 3 23 96 96 3.7 (0.5) 3.7 (0.7)

 4 10 100 100 4.6 (0.9) 2.6 (0.4)

 5 11 100 100 4.6 (0.9) 2.6 (0.4)

 6 11 100 100 1.4 (0.4) 0.7 (0.3)

 7 11 100 100 0.8 (0.1) 0.4 (0.2)

 8 41 98 85 1.0 (0.3) 0.9 (0.1)

 9 28 100 89 1.4 (0.2) 1.0 (0.4)

10 29 90 86 0.9 (0.2) 1.0 (0.3)

11 29 83 79 0.9 (0.2) 0.7 (0.7)

12 39 90 85 0.6 (0.2) 0.8 (0.2)

13 22 86 86 0.4 (0.4) 0.3 (0.3)

14 22 91 91 0.5 (0.6) 1.0 (0.2)

15 21 100 100 0.2 (0.5) 0.7 (0.4)

16 18 78 72 0.5 (0.5) 1.9 (0.4)

Figure 1—Mean heights of AWC stecklings, planted at site 1, 

through the study period, by row. Repeated measures ANOVA 

indicates a significant time*row interaction, suggesting variation in 

performance among rows.
9

these rows ranged from -22 to -33 cm, with a maximum of 

14 cm and a minimum of -45 cm. Stecklings planted in rows 

with a mean water table > -50 cm, exhibited little to no growth 

through the study period.

Site 2

Over 5 years (1996–2000), mean water table depths ranged 

from -6 cm for row 1 to -130 cm for row 5 (table 3). During 

1999, values averaged slightly lower due to drought conditions, ranging from -9 to -137 cm. During 2000, values averaged slightly higher than the 5-year average, ranging from -3 

to -137 cm. Water table depths for row 5 (highest elevation) 

were probably underestimates, as the depth exceeded the 

well length throughout much of the study. 

There were significant differences in survival across rows 

and years (fig. 2) (Chi-square analysis, α = 0.05) in response 

to water table variation. Survival through the 2-year period 

ranged from 12 to 96 percent (table 4). Low water tables 

during 1999, due to drought, decreased survival in row 5—

the row with the highest elevation and deepest water table. 

All stecklings that survived through the first growing season 

also survived through the 2000 season, with the exception of 

row 1. Slightly higher water tables at lower elevations, along

with periods of inundation, led to significant mortality in row 1. 

During 1999, mean height growth ranged from 0.1 cm for 

row 5 to 1.9 cm for row 2. Corresponding values during 2000 

ranged from 0.3 cm for row 5 to 7.0 cm for row 2. Although 

there is a trend toward reduced growth for row 1 (highest 

water table) and row 5 (lowest water table), and greatest 

growth at mid-levels, these differences were not significant 

(repeated measures ANOVA; p = 0.16).

DISCUSSION

As the demand for AWC reforestation and restoration 

increases, it is important to understand the effects of hydrologic variables on such activities, as successful projects will 

depend on adequate hydrologic conditions. We have examined the effects of water table depth on the performance of 

planted AWC stecklings at two highly disturbed sites within 

the New Jersey Pinelands.

Little (1950) observed that first year seedlings grew 2.5 to 

25 cm on favorable sites, with subsequent height growth averaging 30 to 46 cm annually. In the current study, observed 

growth rates at both sites were much lower, probably due 

to the sterile nature of the sites. However, the sterility of the 

sites helped to reduce confounding variables and focus on 

the effects of water table depth on steckling performance 

under field conditions.

Steckling performance was reduced at the greatest water 

table depths, as shown by reduced survival and decreased 

growth rates. At site 1, we found significant differences in 

the height response across rows (each row representing a 

different position along the water table gradient), with the 

greatest growth occurring in rows with an annual mean water 

table depth no greater than -37 cm (fig. 1). At site 2, we 

observed reduced survival at the greatest water table depths 

(row 5; mean water table depth -135 to -140 cm) (fig. 2). 

Steckling performance was also reduced at very high water 

table depths, probably due to long periods of inundation. At 

site 2, we observed reduced survival among row 1 stecklings 

during 2000 (fig. 2). Water table depths during 2000 were 

slightly higher than 1999 and the mean water table depth for 

row 1 was 3 cm below the ground surface. Flooding duration

could not be determined from our data, but may have been 

responsible for the increased mortality. These results, as well

as those of Harrison and others (2003) suggest that newly 

planted AWC individuals are susceptible to high water table 

levels and flooding. Harrison and others (2003) observed 

heavy mortality of seedlings when mean water table depth 

was above the ground surface and suggest that plantings 

Table 3—Mean water table depths (cm) at Site 2, by row. 

Overall mean includes all data throughout the year, 

while growing season mean includes all measurements 

between April and September

Overall Growing season

 1996-

Row 2000 1999 2000 1999 2000

1 -6 -9 -3 -15 -3

2 -25 -29 -24 -34 -24

3 -67 -72 -69 -77 -68

4 -100 -106 -105 -110 -104

5 -130 -137 -137 -141 -136

Figure 2—Percent survival of AWC stecklings, planted at site 2, 

through the study period, by row. 

Table 4—Survival and growth of AWC stecklings planted 

at Site 2, by row. Standard errors are in parentheses

 % Survival Height Growth (cm) 

Row N 1999 2000 1999 2000

1 25 96 28 1.1 (0.5) 1.3 (0.5)

2 25 96 96 1.9 (0.3) 7.0 (1.4)

3 25 64 64 0.3 (0.6) 3.8 (0.9)

4 25 64 64 2.1 (0.7) 4.5 (1.1)

5 25 12 12 0.1 (0.1) 0.3 (0.2)
10

should not be exposed to inundation for more than three 

continuous weeks. Mature stands of AWC commonly experience periods of inundation. Golet and Lowry (1987) studied 

six mature stands in Rhode Island between 1976 and 1982, 

and found that the mean water table depth ranged from 

13 cm above to 11 cm below the ground surface, and the 

duration of surface flooding varied from 18 to 76 percent 

of the growing season. These studies suggest that mature 

individuals may be less susceptible to flooding than young, 

newly planted stock. 

Although we observed variation across sites, similar trends 

are apparent. Best performance was achieved with a mean 

water table depth between approximately -10 and -40 cm. 

Similarly, Harrison and others (2003) found that growth 

increased as the depth to water table increased to -57 cm, 

the maximum depth reported in their study. 

Previous field studies that have examined the effect of water 

table depth on performance of Atlantic AWC regeneration 

have spanned only one season (Harrison and others 2003, 

Mylecraine and others 2003). Our second season results 

indicate significant variability in both water table depths 

and steckling performance across years. This illustrates the 

importance of taking both seasonal and annual variation into 

account when choosing sites based on hydrologic variables.

ACKNOWLEDGMENTS

We would like to thank the late Thorton Hartshorn and 

Clayton Sand and Gravel company for their financial assistance and access to these study sites. We would also like to 

thank Robert Lin for providing water table data from 1996–

1998 and numerous students for help in the field.

LITERATURE CITED

Akerman, A. 1923. The white cedar of the dismal swamp. Virginia 

Forestry Publication 30. Charlottesville, VA: University of Virginia. 

21 p.

Allison, S.K.; Ehrenfeld, J.G. 1999. The influence of microhabitat 

variation on seedling recruitment of Chamaecyparis thyoides and 

Acer rubrum. Wetlands. 19: 383-393.

Frost, C.C. 1987. Historical overview of Atlantic white-cedar in the 

Carolinas. In: Laderman, A.D., ed. Atlantic white-cedar wetlands. 

Boulder, CO: Westview Press: 257-264.

Golet, F.C.; Lowry, D.J. 1987. Water regimes and tree growth in 

Rhode Island Atlantic white cedar swamps. In: Laderman, A.D., 

ed. Atlantic white cedar wetlands. Boulder, CO: Westview Press: 

91-110.

Harrison, J.M.; DeBerry, J.W.; Belcher, R.T. [and others]. 2003. 

Effects of water table on survival and growth of Atlantic white 

cedar swamps in two young, planted sites. In: Atkinson, R.B.; 

Belcher, R.T.; Brown, D.A.; Perry, J.E., eds. Atlantic white cedar

restoration ecology and management: Proceeding of a symposium.

Newport News, VA: Christopher Newport University: 181-196.

Harshberger, J.W. 1916. The vegetation of the New Jersey PineBarrens. Philadelphia, PA: Christopher Sower Company.

Korstian, C.F.; Brush, W.D. 1931. Southern white cedar. Tech. Bull. 

251. Washington, DC: U.S. Department of Agriculture, Forest 

Service. 75 p.

Kuser, J.E.; Zimmermann, G.L. 1995. Restoring Atlantic white-cedar 

swamps: Techniques for propagation and establishment. Tree 

Planters’ Notes. 46: 78-85.

Little, S. 1950. Ecology and silviculture of white cedar and associated hardwoods in southern New Jersey. Yale University School of 

Forestry Bulletin. 56: 1-103.

Mylecraine, K.A.; Zimmermann, G.L. 2003. Atlantic white-cedar: 

Ecology and best management practices manual, 2d

 ed. Trenton, 

NJ: N.J. Department of Environmental Protection, New Jersey 

Forest Service. 

Mylecraine, K.A.; Zimmermann, G.L.; Kuser, J.E. 2003. The effects 

of water table depth and soil moisture on the survival and growth 

of Atlantic white cedar. In: Atkinson, R.B.; Belcher, R.T.; Brown, 

D.A.; Perry, J.E., ed. Atlantic white cedar restoration ecology and 

management: Proceeding of a symposium. Newport News, VA: 

Christopher Newport University: 197-212.

Pinchot, G. 1899. A study of forest fires and wood production in 

southern New Jersey. In: Annual report of the State geologist for 

the year 1898. Trenton, NJ: MacCrellish and Quigley: Appendix 

1-102.

Reed, P.B. 1988. National list of plant species that occur in wetlands: 

Northeast (Region 1). Washington, DC: U.S. Department of the 

Interior, Fish and Wildlife Service.

Ward, D.B. 1989. Commercial utilization of Atlantic white-cedar 

(Chamaecyparis thyoides, Cupressaceae). Economic Botany. 43: 

386-415. 

Zimmermann, G.L. 1997. The Atlantic white-cedar (Chamaecyparis 

thyoides) regeneration experiments: Final report. Pomona, NJ: 

Richard Stockton College of New Jersey. 190 p.
11

INTRODUCTION

Atlantic white cedar [Chamaecyparis thyoides (L.) B.S.P.] 

distribution is restricted to a narrow band of freshwater 

wetlands along the Eastern coastal United States ranging 

from Maine to Mississippi (Laderman 1989). Historically, the 

largest known stand of Atlantic white cedar, estimated at 

26,000 – 45,000 ha, was found in the Great Dismal Swamp 

of Virginia and North Carolina (Frost 1987, Moore and Allen 

1998). 

Historically, Atlantic white cedar has been a valuable timber 

species on the Albemarle-Pamlico peninsula in North Carolina.

Elaborate networks of roads, canals and ditches were constructed to provide direct access to these stands (Laderman 

1989) and these areas have endured draining, nutrient loading, and fire suppression over the centuries (Richardson 1991).

Alligator River and Pocosin Lakes National Wildlife Refuges 

were established to conserve and manage the area’s unique 

wetlands, including Atlantic white cedar forests (Bryant 1999).

They currently contain over 10,000 acres of Atlantic white 

cedar clearcuts and scattered disjunct remnants of Atlantic 

white cedar stands (Eagle 1999). The absence of post-harvest

forest management coupled with poor logging practices and 

hydrologic modifications have resulted in poor Atlantic white 

cedar regeneration in many areas (Eagle 1999). 

Typically, Atlantic white cedar is found on deep organic soils,

as a result of extended hydroperiods and high litter production rates coupled with slow decomposition rates (Day 1987).

Ehrenfeld (1995) has identified the development of a deep peat

substrate as a key component of the structure and function 

of Atlantic white cedar wetlands. Peat deposits strongly affect 

the hydrology of Atlantic white cedar wetlands by increasing 

the water holding capacity of the soil (Levy and Walker 1979)

and are required for seedling recruitment (Beull and Cain 

1943). The wetter hydrologic conditions can lead to anaerobic

conditions and reduced soil pH, which can lead to decreasing

decay rates (Day 1982, Tupacz and Day 1990) ultimately 

affecting nutrient availability and production. As a result, 

hydrologic regimes and carbon cycling are tightly coupled 

mechanisms that either directly or indirectly affect other 

ecosystem functions. The regeneration and development of 

Atlantic white cedar wetlands is dependent on the interplay 

of several environmental drivers including the catastrophic 

disturbance of fire, fire intensity, and ground water elevation 

at the time of fire (Laderman 1989). 

While there are many recent studies examining various 

aspects of Atlantic white cedar restoration (see Shear and 

Summerville 1999), there are no studies documenting decay

processes occurring in Atlantic white cedar restoration sites

(Crawford 2002). Soil organic matter accumulation and 

sequestration are regarded as critical components to 

ecosystem function and self maintenance of these wetlands. 

The objectives of this study were to quantify and compare 

aboveground and belowground decomposition rates within a 

restoration site at Pocosin Lakes National Wildlife Refuge. 

METHODS

Study Site

This study was conducted within a restoration area on a 

former Atlantic white cedar wetland. The site was 3 km south 

of Lake Phelps on F2 road within Pocosin Lakes National 

Wildlife Refuge. The stand was planted with Atlantic white 

cedar seedlings during the fall of 1998. The site was burned 

by fire of unknown cause two years prior to planting and was 

colonized by bracken fern (Pteridium aquilinum [L.] Kuhn.) an 

DECOMPOSITION DYNAMICS IN AN ATLANTIC WHITE CEDAR

RESTORATION SITE

Edward R. Crawford, Frank P. Day, and Robert B. Atkinson1

1 Edward R. Crawford, Instructor, Virginia Commonwealth University, Department of Biology, Richmond, VA 23284; Frank P. Day, Professor, 

Old Dominion University, Department of Biological Sciences, Norfolk, VA 23529; and Robert B. Atkinson, Associate Professor, Christopher 

Newport University, Department of Biology, Chemistry and Environmental Science, Newport News, VA 23606.

Citation for proceedings: Burke, Marianne, K.; Sheridan, Philip, eds. 2005. Atlantic white cedar: ecology, restoration, and management: 

Proceedings of the Arlington Echo symposium. Gen. Tech. Rep. SRS-91. Asheville, NC: U.S. Department of Agriculture, Forest Service, 

Southern Research Station. 74 p.

Abstract—Decomposition dynamics play an important yet little-studied role in organic matter accumulation in Atlantic white 

cedar [Chamaecyparis thyoides (L.) B.S.P.] wetlands. A root decomposition study using a modified litterbag approach and 

a leaf litter decay study using standard litterbags, were conducted within restored Atlantic white cedar wetlands in Pocosin 

Lakes National Wildlife Refuge, North Carolina. The objectives of this study were to quantify aboveground and belowground 

decomposition rates within a restoration setting. Chamaecyparis thyoides (L.) B.S.P. root and leaf litter were deployed as a 

standard substrate. Native leaf litter decay (k = 0.79 yr-1) was significantly higher relative to C. thyoides leaf litter decay (k = 

0.36 yr-1). Across a vertical soil profile, native root decay rates were significantly faster compared to C. thyoides root decay 

rates. These results suggest that within this restoration site, the current status of belowground carbon storage function 

appears to be deficient. Continued long-term study of this and similar restoration sites are need to provide greater insight into 

appropriate recovery models for various wetland functions of Atlantic white cedar.

Keywords: Carbon sequestration, decomposition, histosols, wetland restoration.
12

unidentified Solidago spp. and barnyard grass (Echinochloa 

crusgalli [L.]). The site is on acidic organic soils, which are 

ombrotrophic, and classified as typic haplosaprists (U.S. 

Department of Agriculture 2000). 

Study Design

Two 10 m x 15 m plots (each one containing 48 evenly dispersed 1 m X 1 m subplots) were established for above and 

belowground processes and microenvironmental measurements. Within each subplot, nylon mesh litterbags containing 

native roots and separate bags containing C. thyoides roots 

were inserted into the soil profile during November 1998. The 

litterbags were constructed to integrate the decay process 

over a vertical soil profile (Conn and Day 1997, Tupacz and 

Day 1990). Belowground plant materials (roots and rhizomes, 

where applicable) were collected from pit excavations during 

the summer of 1998 from sites that were representative of 

the dominant community. At this site, Atlantic white cedar 

roots (0.03 grams) were placed into each bag to represent 

the dominant woody component. Upon harvesting, and prior

to placing in litterbags, the root material was washed free of

peat and air dried. Air dry weights were recorded and converted to oven dry weights using conversion factors obtained 

from subsamples of the original belowground material. 

Roots of C. thyoides seedlings donated by Weyerhaueser Corp.

were used as a standard substrate for comparison with decay

rates for the native substrate. Within site comparison of C.

thyoides root decay rates with native root decay rates demonstrated litter quality influences under similar environmental 

conditions. Known weights of air-dried roots were placed in 

nylon mesh litterbags constructed of 1 mm pore size nylon 

mesh and were 40 cm long by 5 cm wide and divided into 

four 10 cm sections. The litterbags were inserted lengthwise

into a vertical slit in the soil with the top of the litterbag positioned at the soil-atmosphere interface. Approximately 3 grams

of root material was placed in each of 4 10-cm sections in 

each litterbag. All roots were between 0.2 and 1.0 cm diameter. Subsamples were oven dried for 48 hours at 75 °C to 

constant mass for air dry:oven dry mass ratios. 

Six root litterbags were collected at each sampling interval

from randomly selected subplots (within each plot) throughout the course of the study. Root samples were installed in 

the field in November 15, 1998 and sampling continued on a

regular basis through January 2000. Over the course of the

study, sampling intervals were approximately 1 month (when

logistically possible). Upon retrieval, the root bags were rinsed

with tap water to remove adhering peat and roots growing 

into the bags were plucked out using forceps. The decomposing substrate was oven dried and weighed to determine 

mass loss. In order to determine ash free dry weight conversion ratios for the samples, individual samples were ground 

in a Wiley mill (40 mesh) and ashed in a muffle furnace at 

550 °C for 5 hours (Allen and others 1986).

Decay rates of leaf litter were also measured. Recently 

senesced leaf litter was collected on site, brought back to 

the lab, and air-dried during the fall of 1998. Approximately 3 

grams of the collected air-dried leaves were placed in 20 cm 

x 20 cm nylon mesh (1 mm hole size) bags. A second group 

of litterbags that contained C. thyoides leaf litter served as 

site controls. The C. thyoides leaf litter was collected during 

the fall of 1998 from an individual tree that fell during late 

summer within the Great Dismal Swamp National Wildlife 

Refuge. Leaf litterbag samples were placed in the field on 

January 15, 1999 and collection coincided with root sample 

collection dates from January 1999 through January 2000. 

Six litterbags of native leaf litter and six litterbags of C. 

thyoides leaf litter were removed from onsite following the 

same protocol described earlier for the root litterbags. Onsite 

water table was determined by the oxidation depth on steel 

rods and soil pH was evaluated over a 0 to 40 cm soil profile. 

Collection of steel rods and soil materials for pH determination coincided with leaf and root litterbag collection. 

Statistical Analyses

The data were evaluated using both linear and exponential 

decay models to test for the best fit. Relative decomposition 

rates (-k [yr-1]) for native and standard leaf litter and roots 

were derived from a fixed-intercept negative exponential 

decay model (Weider and Lang 1982) according to the 

following formula:

X = e-kt (1)

where 

X = the proportion of initial mass remaining

k = the decay constant

t = time 

Significant differences in decay coefficients between 

Chamaecyparis roots and native roots and Chamaecyparis

leaf litter and native leaf litter were detected by t-tests (Zar 

1998). Using the derived k values, time required to reach 1 

percent mass remaining was extrapolated. 

RESULTS

Native leaf litter exhibited greater mass loss relative to 

Chamaecyparis leaf litter over the course of this study (fig. 1).

Native leaf litter decay rates were twice as fast compared 

to Chamaecyparis litter, with time to reach 1 percent mass 

remaining also doubled for Chamaecyparis litter (table 1). 

Figure 1—Percent mass remaining for native and Chamaecyapris 

thyoides leaf litter at Pocosin Lakes National Wildlife Refuge. Values 

represent means with one standard error. Percent mass remaining 100

80

60

40

20

0

Days

 0 50 100 150 200 250 300 350 400

Native litter

Chamaecyparis litter
13

T-tests between native leaf litter and Chamaecyparis leaf 

litter revealed significant differences (p = 0.05) between 

decay rates (table 1). 

Native roots exhibited greater mass loss over time relative to

Chamaecyparis roots (fig. 2). There was a trend of decreasing

mass loss with increasing depth of the vertical soil profile for

both native and standard roots (fig. 2). Native root decay rates

were more than doubled in the 0 to 10 cm depth interval and

nearly doubled in the 10 to 20 cm depth interval relative to

Chamaecyparis roots (fig. 2). Across all depth intervals, t-tests

revealed significant differences (p = 0.05) between native 

root decay and Chamaecyparis root decay (table 1). 

Mean soil pH was 3.5, and there was little temporal or spatial 

variation over the soil profile throughout the study (fig. 3). 

Depth of water table, as indicated by oxidation depth on steel 

rods, varied seasonally with water table deepest during the 

summer of 1999 and most shallow during the winter and fall 

of 1999 (fig. 4). 

DISCUSSION

Regeneration of Atlantic white cedar in the mid-Atlantic region

has been hindered due to shade intolerance, hydrologic modifications (Hinesley and Wicker 1999) and herbivory by deer, 

mice, and rabbits (Guidry 1999). These hindrances were 

present at the Pocosin Lakes restoration site during this 

study (personal observation). 

Decay rates were faster for native leaf litter relative to Chamaecyparis leaf litter at Pocosin Lakes National Wildlife Refuge. 

This was not unexpected as the native leaf litter was dominated by graminoids and forbs and Benner and others (1985) 

found that the lignocelluloses from herbaceous plants were 

mineralized several times faster relative to woody species 

under similar environmental conditions. The decay rate of 

Chamaecyparis litter (k = 0.36 yr-1) was well within the range 

of values reported for other regional restored and regenerating sites (Crawford 2002) and similar to those reported 

for Atlantic white cedar by Day (1982) and Yates and Day 

(1983).

The average soil pH was also within the range of those 

reported for other restored/regenerating stands in the region 

(Crawford 2002, Thompson 2001) and also within the range 

found for other regional Atlantic white cedar stands (Tupacz 

and Day 1990, Whigham and Richardson 1988). Based on 

hydrology data inferred from rusting depth on steel rods, with 

the exception of summer drought during 1999, antecedent 

and post drought water tables were comparable with other 

East Coast Atlantic white cedar wetlands (Golet and Lowry 

1987). 

Both native and Chamaecyparis roots had decreasing root

decay rates with increasing depth in the soil profile, however,

native root decay was significantly faster than Chamaecyparis

root decay within each depth interval. Similar trends were 

also exhibited in other Atlantic white cedar restoration sites 

in the study region (Crawford 2002). Native root decay rates 

at Pocosin Lakes National Wildlife Refuge were similar to 

those of other regional restoration sites. Decay rates of 

Chamaecyparis roots were similar to those found in a similar 

study of stands within Great Dismal Swamp and Alligator 

River National Wildlife Refuges (Crawford 2002). In that study,

the highest rates of both native and Chamaecyparis root 

decay occurred in the 0 to 10 cm depth interval and is likely a 

result of aerobic conditions found at that interval. Oxidation 

depth on steel rods within the study site was consistently 

greater than 10 cm below the soil surface over the course of 

the study. 

Table 1—Decay rate constants [-k (per year)], coefficient of determiniation 

(r2), time to reach 1 percent mass remaining (t0.01), and percent mass 

remaining after 370 days of decay (percent M)a 

 

Litter Depth Final

type class k SE r2 t0.01 mass

cm year percent

Leaf

Native 0.79A 0.05 0.96 5.82 47.50

Chamaecyapris 0.36B 0.07 0.98 12.79 69.54

 

Root

Native 0 – 10 0.78A 0.03 0.98 5.82 48.76

10 – 20 0.57A 0.04 0.95 8.07 62.97

20 – 30 0.54A 0.02 0.97 8.52 62.59

30 – 40 0.50A 0.03 0.95 9.21 63.06 

Chamaecyparis 0 – 10 0.36B 0.03 0.93 12.79 75.64

10 – 20 0.34B 0.02 0.95 13.54 76.14

20 – 30 0.30B 0.01 0.96 15.35 76.60

30 – 40 0.28B 0.02 0.96 16.44 77.63

a All regressions are significant at p = 0.0001. Different uppercase letters indicate significant 

differences (p = 0.05) between native and Chameacyparis litters. 
14

Figure 2—Percent mass remaining of native and Chamaecyparis thyoides root litter at Pocosin Lakes National 

Wildlife Refuge. Values represent means with one standard error.

Figure 3—Vertical gradient in soil pH within Pocosin Lakes National Wildlife Refuge. Values represent 

means with one standard error. Sampling interval refers to nine collection periods between January 1999 

and January 2000.
15

Findings of this study suggest that decomposition of native 

roots and leaf litter is faster relative to Chamaecyparis root 

and leaf litter decay. Future increases in above and belowground production of Atlantic white cedar coupled with the 

low decay rates of cedar litter could result in increased 

contributions to soil organic matter pools and greater carbon 

sequestration as this restored site matures. 

AKNOWLEDGMENTS

The authors wish to thank two anonymous reviewers for 

their helpful comments and suggestions. Thanks to LeRoy 

Rodgers, Todd Herbert, Jeff DeBerry, Bob Belcher, Darren 

Loomis and Mark Kalnins who all provided capable assistance

in the field. Dr. Gary Whiting provided assistance and guidance in the field and laboratory. We gratefully acknowledge 

the logistical support and assistance from the refuge staff 

of Pocosin Lakes National Wildlife Refuge. Funding for this 

research was provided by a subcontract to Frank Day at Old 

Dominion University from Christopher Newport University 

through the U.S. Environmental Protection Agency STAR 

grant No. R825799.

LITERATURE CITED

Allen, S.H.; Grimshaw, H.M.; Rowland, A.P. 1986. Chemical analysis. 

In: Moore, P.D.; Chapman, S.B., eds. Methods in plant ecology. 

London, England: Blackwell Scientific: 285-344.

Benner, R.M.; Moran, A.; Hodson, R.E. 1985. Effects of pH and 

plant source on lignocellulose biodegradation rates in two wetland 

ecosystems, the Okeefenokee Swamp and a Georgia salt marsh. 

Limnology and Oceanography. 30: 489-499.

Beull, M.F.; Cain, R.L. 1943. The successional role of southern white 

cedar (Chamaecyparis thyoides) in southeastern North Carolina. 

Ecology 24: 85-93.

Bryant, M.R. 1999. Linking ecosystem management, refuge management and Atlantic white cedar restoration. In: Shear, T.H.; 

Summerville, K.O., eds. Atlantic white-cedar: Ecology and management symposium. Gen. Tech. Rep. SRS–27. Asheville, NC: U.S. 

Department of Agriculture, Forest Service, Southern Research 

Station: 8-9.

Conn, C.E.; Day, F.P. 1997. Root decomposition across a barrier 

island chronosequence: Litter quality and environmental controls. 

Plant and Soil 195: 351-364.

Crawford, E.R. 2002. Decomposition dynamics in restored and naturally recovering Atlantic white cedar (Chamaecyparis thyoides) 

wetlands. Norfolk, VA: Old Dominion University. Ph.D Dissertation.

Day, F.P. 1982. Litter decomposition rates in the seasonally flooded 

Great Dismal Swamp. Ecology 63: 670-678.

Day, F.P. 1987. Production and decay in (Chamaecyparis thyoides) 

swamps in southeastern Virginia. In: Laderman, A.D., ed. Atlantic 

white cedar wetlands. Boulder, Colorado: Westview Press: 

123-132.

Eagle, T.R. 1999. Atlantic white-cedar ecosystem restoration on 

Alligator River National Wildlife Refuge and United States Air 

Force Dare County Range. In: Shear, T.H.; Summerville, K.O., eds. 

Atlantic white-cedar: Ecology and management symposium. Gen. 

Tech. Rep. SRS–27. Asheville, NC: U.S. Department of Agriculture, 

Forest Service, Southern Research Station: 13-17.

Ehrenfeld, J.G. 1995. Microsite differences in surface substrate 

characteristics in (Chamaecyparis) swamps of the New Jersey 

pinelands. Wetlands 15: 183-189.

Frost, C.C. 1987. Historical overview of Atlantic white cedar in the 

Carolinas. In: Laderman, A.D., ed. Atlantic white cedar wetlands. 

Boulder, CO: Westview Press: 257-264.

Golet, F.C.; Lowry, D.J. 1987. Water regimes and tree growth in 

Rhode Island Atlantic white cedar swamps. In: Laderman, A.D., 

ed. Atlantic white cedar wetlands. Boulder, CO: Westview Press: 

91-110.

Guidry, J.L. 1999. Effects of herbivore pressure on Atlantic white 

cedar rooted-cutting survival on a North Carolina Coastal Plain 

peatland. In: Shear, T.H.; Summerville, K.O., eds. Atlantic whitecedar: Ecology and management symposium. Gen. Tech. Rep. 

SRS–27. Asheville, NC: U.S. Department of Agriculture, Forest 

Service, Southern Research Station: 18-21.

Hinesley, E.; Wicker, M. 1999. Atlantic white-cedar restoration project

at Pocosin Lakes National Wildlife Refuge. In: Shear, T.; Summerville, K.O., eds. Proceedings: Atlantic white-cedar: Ecology and 

management symposium. Gen. Tech. Rep. SRS–27. Asheville, 

NC: U.S. Department of Agriculture, Forest Service, Southern 

Research Station: 27-33.

Laderman, A.D. 1989. The ecology of Atlantic white cedar wetlands: 

a community profile. U.S. Department of Interior, Fish and Wildlife 

Service, Research and Development, National Wetlands Research 

Center. Biological Report. 85(7.21).

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In: Kirk, P., ed. The Great Dismal Swamp. Charlottesville, VA: 

University Press of Virginia: 101-126.

Moore, S.E.; Allen, H.L. 1998. Vegetative composition and height 

growth of a 4-year old Atlantic white cedar (Chamaecyparis 

thyoides) stand under varying combinations of above- and belowground competition. In: Rose, R.K., ed. The Natural History of the 

Great Dismal Swamp. Madison, WI: Omni Press.

Richardson, C.J. 1991. Pocosins: an ecological perspective. 

Wetlands 11: 335-354.

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Ecology and management symposium. Gen. Tech. Rep. SRS–27. 

Asheville, NC: U.S. Department of Agriculture, Forest Service, 

Southern Research Station.

Thompson, G.S. 2001. Assessment of soil biochemistry in regional 

Atlantic white cedar swamps. Newport News, VA: Christopher 

Newport University. M.S. thesis.

Tupacz, E.G.; Day, F.P. 1990. Decomposition of roots in a seasonally 

flooded swamp ecosystem. Aquatic Botany 37: 199-214.

Figure 4—Depth to standing water at Pocosin Lakes National Wildlife 

Refuge as determined by rusting depth on steel rods. Values represent means with one standard error. Sampling interval refers to nine 

collection periods between January 1999 and January 2000. Depth to standing water (cm)

0

-10

-20

-30

-40

-50

-60

-70

Sampling interval

 0 = soil surface
16

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Service. 2000. National Soil Survey Center. http://rmhost.cpd.

state.neus/~nslsoil/soil.html. [Date accessed: March 25, 2001].

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used in examining decomposition data obtained from detritus 

bags. Ecology 63: 1636-1642.

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of an Atlantic white cedar wetland on the inner Coastal Plain of 

Maryland. Canadian Journal of Botany. 66: 568-576.

Yates, F.R.; Day, F.P. 1983. Decay rates and nutrient dynamics in 

confined and unconfined leaf litter in the Great Dismal Swamp. 

The American Midland Naturalist 110: 37-43.

Zar, J.H. 1998. Biostastical Analysis. Upper Saddle River, NJ: 

Prentice Hall.
17

INTRODUCTION

Atlantic white cedar [Chamaecyparis thyoides (L.) B.S.P.] is 

an evergreen conifer that grows in fresh water swamps and 

bogs along a narrow coastal belt from southern Maine to 

northern Florida and west to southern Mississippi (Laderman 

1989). The wood is lightweight, fragrant, straight-grained, 

easily machined, extremely resistant to decay, and is not 

prone to crack or check (Hinesley and Wicker 2003). All these

traits made it highly prized for boats, siding, and shingling in 

the past. Historically, white cedar was the most valuable tree 

in the Albemarle Peninsula in the coastal plain of eastern 

North Carolina (Krinbill 1956). It had a stumpage value up to

five times greater than other species, and special effort was

made to accurately locate all stands so they could be reached

with minimum construction of railroad spurs (Krinbill 1956). 

Current demands for the lumber include telephone poles, 

piling, ties, siding, and boat railing. The acreage of Atlantic 

white cedar (AWC) today is only a small fraction of the 

original (Davis and others 1997, Frost 1987, Kuser and 

Zimmermann 1995, Lilly 1981) due not only to logging, 

but also wildfires and drainage of peatlands for agricultural 

purposes (Hinesley and Wicker 2003). 

Restoration of AWC ecosystems is a high priority in the 

forested wetlands of eastern North Carolina. However, a 

serious obstacle in replenishing AWC is lack of planting stock;

until that problem is resolved, little progress will be made. 

AWC is relatively easy to vegetatively propagate from stem 

cuttings (Boyle and Kuser 1994, Hinesley and others 1994, 

Hinesley and Snelling 1997), but that method has drawbacks, 

including high labor intensity and costs. Comparisons of 

growth for seedlings and rooted cuttings the first few years in 

the field have yielded mixed results (Kuser and Zimmermann 

1995, Phillips and others 1998). In addition, seedlings 

have more genetic diversity that serves as a buffer against 

environmental and biotic adversity (Kuser and Zimmermann 

1995). However, also unknown is the long-term performance 

of rooted cuttings.

In North Carolina, production of AWC in outdoor nursery 

beds has been hampered by several problems including low 

utilization efficiency of seed, and poor control of seedbed 

density. Current efforts are focused on production of containerized seedlings and transplants from seed. 

Atlantic white cedar is an obligate wetland species (Reed 

1988) that can tolerate an elevated water table. An important issue in refining the science of container production 

is frequency and quantity of irrigation. Too much water is 

not good, whereas too little water can stress seedlings and 

reduce their growth. Consequently, our objective was to 

examine the growth and morphology of white cedar seedlings in response to varying water table depths, at or near 

saturation, over a range of temperature regimes.

MATERIALS AND METHODS

On January 29, 2002, containerized AWC seedlings were 

graded by size and planted into standard 1 gallon pots 

(Nursery Suppliers Classic 300, height = 18.5 cm) containing 

a substrate of pine bark (filled to depth of 17 cm) with one 

seedling per pot. The planted pot was then nested inside 

another Classic 300 pot without drainage holes. Four equally 

spaced 1.3-cm drainage holes were previously drilled into 

the outer pot according to assigned water table level: no 

water table (well drained), one-third full, two-thirds full, and 

flooded (water at the surface of the substrate). Ten additional 

seedlings were randomly sampled for initial height (cm), and 

stem diameter (mm) was determined with a digital caliper 

near ground line. Roots and shoots were dried to constant 

weight gram at 65 °C.

WATER TABLE AND TEMPERATURE REGIME AFFECT GROWTH OF 

POTTED ATLANTIC WHITE CEDAR

Scott A. Derby and L. Eric Hinesley1

1 Scott A. Derby, Research Technician, and L. Eric Hinesley, Professor, North Carolina State University, Dept. of Horticultural Science, Raleigh, 

NC 27695-7609.

Citation for proceedings: Burke, Marianne, K.; Sheridan, Philip, eds. 2005. Atlantic white cedar: ecology, restoration, and management: 

Proceedings of the Arlington Echo symposium. Gen. Tech. Rep. SRS-91. Asheville, NC: U.S. Department of Agriculture, Forest Service, 

Southern Research Station. 74 p.

Abstract—Atlantic white cedar [Chamaecyparis thyoides (L.) B.S.P.] seedlings were grown for 16 weeks at 18/14 °C, 22/18 

°C, or 26/18 °C in controlled-environment chambers. Four water table treatments were used in 20-cm pots (pot-in-pot) 

containing a pinebark substrate: (1) control (fully drained), (2) one-third full, (3) two-thirds full, and (4) completely full. Pots 

were watered twice daily with deionized water. They were fertilized once weekly with a modified Hoagland’s solution (3 to 

4 hours); then, flushed and refilled with deionized water. Growth (height, stem diameter, and dry weight) increased with 

increasing temperature regime, but temperature effects were minimal for flooded plants. For most variables, the relationship 

of water table to growth was quadratic; linear for temperature. Maximum height and dry weight occurred when pots were onethird to two-thirds full of water. Flooded plants yielded far less growth and had lower height/diameter ratios compared to other 

water regimes. Root systems of flooded plants tended to form a mat near the soil surface. 

Keywords: Chamaecyparis thyoides, containerized plants, controlled-environment, flooded, irrigation, root system, seedlings, 

wetland restoration.
18

Plants were fumigated overnight in the Southeastern Plant 

Environment Laboratory at North Carolina State University. 

The next day, pots were set on mobile carts and placed in 

three walk-in growth chambers: 18/14 °C, 22/18 °C, and 

26/22 °C day/night temperatures, all under long-day conditions. Day lighting occurred for 9 hours and was derived from 

cool white fluorescent and incandescent lighting providing a 

photosynthetic photon flux density (PPFD) of 639 μmol m-2 

s-1. Plants received a 3-hour night interrupt with 58 μmol m-2 

s-1 of incandescent lighting from 2300 to 0200 hours (Downs 

and Thomas 1991).

The study design was a randomized complete block within 

each chamber. The four water tables represented treatments,

and each replication had four, single-tree plots, i.e., pots. 

Each cart held two replications (eight pots), and each chamber had five carts for 10 replications (40 plants). Plants were 

hand watered with deionized water twice daily. Once each 

week, the outer pot was removed from each container to 

allow drainage, and the substrate was saturated with a modified Hoagland’s nutrient solution (Downs and Thomas 1991). 

After 1 hour, pots were thoroughly rinsed of the fertilizer solution; then, water tables were restored.

Plants were measured for height and stem diameter once 

monthly. The study was concluded on May 30, 2002, after 16 

weeks. Following final measurement, plants were divided into 

roots and shoots, and dried to constant weight at 65 °C prior 

to weighing.

Using SAS (SAS Institute 2000), data were checked for 

normality and homogeneity of variance, and then analyzed 

using GLM procedures. Owing to several “temperature x 

flood treatment” interactions, the analysis was also carried 

out for each temperature regime separately (table 1). Linear 

and quadratic effects were tested for temperature, and a 

cubic effect was included with flood treatments.

Table 1—GLM analysis for growth of potted Atlantic white cedar seedlings subjected to four water table levels and three temperature regimes Stem Ht/diam Dry weight

Source df Height diam. ratio Root Shoot Total 

18/14 °C 

W 3 ** * * ** ** **

 lin 1 NS NS * **  

 quad 1 **  ** NS   ** 

 cubic 1 * NS NS NS NS NS

Error 27 — — — — — — 

 R2 0.60 0.49 0.57 0.65 0.51 0.58 

22/18 °C 

W 3 ** NS   **  **

 lin 1 NS NS ** ** * **

 quad 1 ** NS   **  **

 cubic 1 NS NS NS NS NS NS

Error 27 — — — — — — 

 R2 0.54 0.39 0.54 0.73 0.54 0.64 

26/22 °C 

W 3   **  **  

 lin 1 **  NS **   ** 

 quad 1 ** ** * ** ** **

 cubic 1 NS NS NS NS * *

Error 27 — — — — — — 

 R2 0.60 0.61 0.55 0.87 0.82 0.85 

Combined 

T 2 **   **  ** **

 lin 1   **  **  

 quad 1 **  NS NS NS * NS

Rep(T) 27 — — — — — — 

W 3 **   **  ** **

T x W 6 ** NS * NS ** **

Error 81 — — — — — — 

 R2 0.76 0.71 0.61 0.81 0.82 0.83

W = water table level; T = temperature regime; **, *, NS = significant or not 

significant at P < 0.01 or 0.05 respectively.
19

RESULTS

In general, there was a quadratic relationship between water 

table level and various indices of growth, with maximum 

values in pots that were one-third to two-thirds full (table 1) 

(fig. 1). Saturated conditions sharply reduced height and dry 

weight (fig. 1). 

The relationship between temperature and growth was 

quadratic for shoot weight and height, but linear for stem 

diameter, root weight, and total weight (table 1) combined 

analysis. The temperature effect was most evident in unsaturated conditions (pots ≤ one-third or two-thirds full) (fig. 1) 

(all panels), i.e., going from 22/18 °C to 26/22 °C increased 

growth more than an increase from 18/14 °C to 22/18 °C. 

Under unsaturated conditions, 26/22 °C yielded about 50 

percent more shoot weight (fig. 1A) and 30 percent more 

root weight (fig. 1B) than 22/18 °C. Root weight of flooded 

plants was 35 to 40 percent of the maximum values for lower 

water tables (fig. 1B). Plants at 26/22 °C had 50 percent and 

80 percent more total weight (roots plus shoot) than those 

at 22/18 °C and 18/14 °C, respectively (fig. 1C). Total weight 

of flooded plants was only 36 to 49 percent of the maximum 

values for other water table levels. 

Figure 1—Shoot weight, root weight, total weight, height, stem diameter, and height/diameter 

ratio for potted Atlantic white cedar seedlings grown for 16 weeks at 18/14 °C, 22/18 °C or 

26/22 °C. (A) shoot dry weight, (B) root dry weight, (C) total dry weight, (D) height, (E) stem 

diameter, and (F) height/diameter ratio. Each “temperature x water table” mean was based on 

10 plants, and in general, the standard error of the mean was 2 percent to 5 percent of the 

mean value.
20

Maximum height (30 cm) occurred at 26/22 °C (water table = 

1/3), 78 percent more than the saturated treatment (17 cm), 

and 13 percent more than the control treatment (fig. 1D). 

Height was smallest at 18/14 °C, where plants in pots that 

were two-thirds full were 34 percent taller than flooded plants 

(18.0 vs. 13.4 cm, respectively).

Maximum stem diameter occurred in pots that were twothirds full (fig. 1E). For all water table levels, stem diameters 

were about 30 percent larger at 26/22 °C compared to 18/14 

°C. As with other measures of growth, height/diameter (h/d) 

ratios were highest for water table levels of one-third and 

two-thirds (fig. 1F). H/d ratios were sharply lower—and very 

similar—under saturated conditions, indicating that those 

plants were stouter than others in relation to their height. By 

the end of the experiment, all treatments had h/d ratios lower 

than the initial value of 5.8. 

DISCUSSION

In forested wetlands, water tables fluctuate seasonally as 

well as in response to isolated storm events. The ability of 

plants to tolerate flooding is affected by many factors, e.g., 

species, season, water temperature, oxygen content, and 

water movement. It would likely require a long series of 

experiments to determine the response of AWC to various 

combinations of factors bearing on this question. Even though

our experiment did not simulate natural conditions, owing 

to constant water tables, it still allowed inferences about the 

response of AWC to water tables at or near the soil surface.

In general, the response of various growth indices to water 

table depth was quadratic (table 1) (fig. 1). The best growth, 

which occurred in moderately flooded treatments, was 

consistent with published data stating that water table levels 

in white cedar stands are typically within 10 to 20 cm of the 

soil surface during the growing season (Harrison and others 

2003, Little 1950, Reynolds and others 1981), though there 

can be considerable variation from site to site (Atkinson and 

others 2003, Duttry and others 2003, Mylecraine and others 

2003) and year to year (Golet and Lowry 1987). 

Saturation resulted in little growth except for stem diameter,

with treatment differences most dramatic in root dry weight 

and total dry weight (fig. 1). This verifies published data in 

which AWC and nine other taxa were flooded for 28 days 

during the growing season (Holland and others 2003). Relative root growth declined 10 percent at 22/18 °C and 22 

percent at 30/26 °C. In both temperature regimes, AWC 

was least negatively impacted by flooding. While no plants 

died in our experiments, Harrison and others (2003) found 

a negative relationship between flooding and survival in 

natural stands, where inundation was present for half of 

the growing season. Growth of AWC tends to decrease on 

excessively wet sites (Little 1950), likely due to inadequate 

aeration of the rhizosphere. In our study, plants growing in 

a saturated substrate developed a mat of roots at the soil 

surface, suggesting a degree of morphological adaptability in 

response to waterlogged conditions.

In general, growth of seedlings increased linearly in response

to temperature (table 1), confirming previous research with 

AWC seedlings (Jull and others 1999). It would be interesting

to examine the response to temperature regimes of say 

30/26 °C or slightly greater, more representative of the 

plant’s southern range mid-growing season temperatures.

We showed that production of containerized AWC can supply 

planting stock for future regeneration efforts and that white 

cedar not only tolerates but also thrives with heavy irrigation 

as long as plants are not flooded. Under experimental conditions, potted plants subjected to shallow water tables yielded 

as much or more growth than well-drained plants. Clearly, it 

would be difficult to overwater AWC in drained containers. 

Heavy watering would not impair growth, although it might 

lead to excessive leaching of nutrients. Conversely, applying 

too little water, resulting in a dry substrate, would probably 

reduce growth.

ACKNOWLEDGMENTS

This research was partly funded by U. S. Fish & Wildlife 

Service grant No. 1448-40181-01G041.

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Atkinson, R.B.; DeBerry, J.W.; Loomis, D.T. [and others]. 2003. 

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restoration. In: Atkinson, R.B.; Belcher, R.T.; Brown, D.A.; Perry, 

J.E. eds. Proceedings Atlantic white cedar restoration ecology 

and management symposium. Newport News, VA: Christopher 

Newport University: 137-150.

Boyle, E.D.; Kuser, J.E. 1994. Propagation of Atlantic white cedar by 

seed and cuttings in New Jersey. Tree Planters’ Notes 45: 104-111.

Davis, K.N.; Henderson, B.; Daniels, S. 1997. Inventory of Atlantic 

white cedar remnant stands in North Carolina. U.S. Air Force. BPA 

No. F31610-95-AV026.

Downs, R.J.; Thomas, J.F. 1991. Phytotron procedural manual for

controlled-environment research at the Southeastern Plant 

Environment Laboratory, rev. North Carolina Agricultural Research 

Service. Tech. Bull. 244.

Duttry, P.M.; Atkinson, R.B.; Whiting, G.J. [and others]. 2003. Soil 

respiration response to water levels of soils from Atlantic white 

cedar peatlands in Virginia and North Carolina. In: Atkinson, R.B.; 

Belcher, R.T.; Brown, D.A.; Perry, J.E., eds. Proceedings Atlantic 

white cedar restoration ecology and management symposium. 

Newport News, VA: Christopher Newport University: 165-174. 

Frost, C.C. 1987. Historical overview of Atlantic white cedar in the 

Carolinas. In: Laderman, A.D., ed. Atlantic white cedar wetlands. 

Boulder, CO: Westview Press: 257-264.

Golet, F.C.; Lowry, D.J. 1987. Water regimes and tree growth in 

Rhode Island Atlantic white cedar swamps. In: Laderman, A., ed. 

Atlantic white cedar wetlands. Boulder CO: Westview Press: 91-110.

Harrison, J.M.; Deberry, J.W.; Belcher, R.T. [and others]. 2003. 

Effects of water table on survival and growth of Atlantic white 

cedar in two young planted sites. In: Atkinson, R.B.; Belcher, R.T.; 

Brown, D.A.; Perry, J.E., eds. Proceedings: Atlantic white cedar 

restoration ecology and management symposium. Newport News, 

VA: Christopher Newport University: 181-196.

Hinesley, L.E.; Blazich, F.A.; Snelling, L.K. 1994. Vegetative propagation of Atlantic white cedar by stem cuttings. HortScience 29: 

217-219.

Hinesley, L.E.; Snelling, L.K. 1997. Rooting stem cuttings of Atlantic 

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Hinesley, L.E.; Wicker, A.M. 2003. Research at N.C. State University 

related to regeneration of Atlantic white cedar and baldcypress. 

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Holland, B.T.; Warren, S.L.; Ranney, T.G. 2003. Evaluating recovery 

of cupressaceae taxa after flooding at contrasting temperatures. 

Journal Environ. Horticulture 21: 51-55.

Jull, L.G.; Ranney, T.G.; Blazich, F.A. 1999. Heat tolerance of 

selected provenances of Atlantic white cedar. Journal American 

Society Horticultural Science. 124: 492-497.

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22

INTRODUCTION 

Atlantic white cedar (AWC), [Chamaecyparis thyoides (L.)] 

ecosystems in the Northeastern United States are deemed 

threatened because of their rarity in the landscape. New 

Jersey’s AWC population has decreased 74 percent from its 

estimated historic area (from 47,000 ha down to 12,100 ha) 

(New Jersey Department of Environmental Protection 2003). 

In the glaciated Northeast, only 5,300 ha of AWC swamp 

remain (Motzkin 1991). The primary causes of their net loss 

over the last two centuries are logging and habitat destruction (Laderman 1989).

Atlantic white cedar is important commercially and has been 

heavily logged since colonial times because of its workability 

and resistance to decay and insects. AWC has been historically used for shingles, barrels, and boats. Today it is still 

an important commercial tree in New Jersey, Virginia, the 

Carolinas, and Florida, and is often used for telephone poles, 

piling, ties, and siding (Little and Garrett 1990). 

Atlantic white cedar ecosystems are ecologically important 

because they provide unique cover, habitat, and food for a 

variety of fauna. For example, a plant survey of a recently 

discovered AWC community in west central Georgia contributed significantly to the knowledge of rare plant occurrence 

within the region (Sheridan and Patrick 2003). The larva of 

the endangered Hessel’s Hairstreak butterfly (Callophrys 

hesseli Rawson and Ziegler) feed solely on AWC leaves in 

Maine (Kluge 1991). White-tailed deer (Odocoileus virginianus Boddaert) preferentially eat AWC seedlings as a food 

source (Dickerson 2002). Therefore, studying, protecting, and 

managing AWC ecosystems is beneficial both for commercial 

and ecological reasons.

Atlantic white cedar grows along the Eastern Coast of the

United States no more than 130 miles inland, with its northern

range limit in south central Maine (Little and Garrett 1990). 

Because of its economic and ecological value and threatened

status as an ecosystem, it is important to understand what 

factors limit the growth of AWC for future management and 

conservation. Studying AWC’s climatic sensitivity is especially important in the face of potential rapid climate change 

although the species is not traditionally used in dendrochronological research. Nevertheless, Golet and Lowery (1987) 

found that changes in measured relative ring width could 

be explained by variations in water level in several Rhode 

Island AWC swamps. However, they concluded that their 

findings were wetland specific without a strong regional 

climatic signal. Pederson and others (2004) found AWC to be 

very temperature sensitive in southern New York State and 

northern New Jersey region. It is not known if this sensitivity 

can be extended to a regional scale. 

The objectives of this study were to: (1) identify how well AWC

crossdate (agreement in population’s annual radial growth 

variations), (2) improve our understanding of the climate 

response of AWC, and (3) study its growth over the last 100 

years. Specifically we tested whether the trees along their 

northern range limit show sensitivity to climate and if so, 

which climatic variables account for variations in annual ring 

widths. Although not often tested in temperate regions, it is 

thought that trees are more sensitive climatically at range 

limits. Research on loblolly pine (Pinus taeda L.) indicates 

that cool temperatures only became a growth-limiting factor 

at its northern range limit (Cook and others 1998). Therefore, 

we hypothesized that radial growth at the northern range limit 

for AWC was most limited by temperature of the previous 

and current growing season.

PROCEDURE

Increment cores were collected from seven different sites 

along the northern edge of Atlantic white cedar range limit:

CLIMATE SENSITIVITY OF ATLANTIC WHITE CEDAR

AT ITS NORTHERN RANGE LIMIT

H. Myvonwynn Hopton and Neil Pederson1

1 H. Myvonwynn Hopton, Consultant, and Neil Pederson, Graduate Research Assistant, Lamont-Doherty Earth Observatory, Columbia University, 

Tree-Ring Lab, Palisades, NY 10964.

Citation for proceedings: Burke, Marianne, K.; Sheridan, Philip, eds. 2005. Atlantic white cedar: ecology, restoration, and management: 

Proceedings of the Arlington Echo symposium. Gen. Tech. Rep. SRS-91. Asheville, NC: U.S. Department of Agriculture, Forest Service, 

Southern Research Station. 74 p.

Abstract—Atlantic white cedar is a wetland tree species with ecological and commercial importance that is distributed 

primarily along the Atlantic seaboard to south central Maine. The number of AWC swamps has declined due to human 

impacts. The potential for rapid climate change and AWC’s threatened status make it important to study factors affecting 

its growth, especially climate. The objectives of this study are to determine the usefulness of AWC for tree-ring analysis, its 

sensitivity to climate along its northern range limit, and to study its growth rates. Seven AWC populations from northern New 

Jersey to southern Maine were found to be sensitive to changes in its environment. Growth was most commonly correlated 

to prior May and June, winter through spring, and current July and August temperatures. Decadal variations in temperature 

closely mirror variations in AWC growth suggesting that temperature is the primary limiting factor across the region from 1902 

to 1995.

Keywords: Climate change, northern range limit, temperature, tree growth, tree productivity. 
23

Appleton Bog, ME, Saco Heath, ME, Westminster, MA, 

Monson, MA, North Madison, CT, High Point, NJ, and 

Uttertown, NJ (fig. 1). To characterize forest composition at 

each site, four measurements of basal area (BA) using a 

cruise prism were taken at every fourth or fifth tree cored and 

averaged. Here we report only those species making up > 10 

percent of stand BA (table 1).

Cores were collected and processed using standard dendrochronological techniques (Fritts 1976, Stokes 1968). Dr. 

Thomas Siccama and his students at Yale University collected

cores from North Madison Cedar Swamp, Connecticut in 

1988, 1991, and 1992. The cores were loaned to the LamontDoherty Tree Ring Lab for this study. Basal area measurements

were not available for this site. From each of the other sites, 

cores were collected from at least 20 different trees using 

a hand-operated increment borer, except for Monson, MA 

due to its lack of old trees. Since climate response was the 

focus of this study, healthy dominant older looking trees were 

selected for coring so as to maximize the climate response. 

This non-random selection may not fully represent the standlevel climate response. However, some research suggests 

that competition can obscure the temperature signal in trees 

(Cescatti and Piutti 1998). Also, trees in declining health may

be unresponsive to climate. Therefore, in keeping with the

study’s main goal we avoided sampling understory or 

unhealthy appearing trees. To maximize the geographic 

coverage while minimizing field and laboratory time, a single 

core was taken from each tree sampled. A second core 

was occasionally taken if the tree appeared old to increase 

sample replication and strengthen the cross-dating. This is 

less than the typical tree ring protocol of two cores per tree. 

However, tree replication is more efficient than core replication in reducing estimated mean standard error (Fritts 1976). 

Once the cores were extracted, they were stored in labeled 

plastic straws for transport back to the Lamont-Doherty Tree 

Ring Lab, Palisades, NY. 

Figure 1—Atlantic white-cedar populations sampled in the Northeastern United States: 

1 - Appleton Bog, ME; 2 - Saco Heath, ME; 3 - Westminster, MA; 4 - Monson Cedar Swamp,

MA; 5 - North Madison Swamp, CT; 6 - High Point, NJ; 7 - Uttertown Bog, NJ. Stippled area 

represents the northern distribution of Atlantic white-cedar as adapted from Little (1971).

1

2

3

4

5

6

7
24

At the lab, the cores were air-dried and then glued to wooden 

mounts. The cores were sanded with increasingly finer sandpaper up to 600 grit. The cores were then examined under a 

microscope and visually cross-dated. Rings were measured 

to the nearest 0.001 mm. Visual cross-dating was verified 

using the program COFECHA (Holmes 1983). Correctly dated

time-series of growth were standardized using a double 

detrending method with the intent to preserve as much low 

frequency information as possible unrelated to competition

(Cook and Kairiukstis 1990). First, a negative exponential 

curve or linear regression was used to remove geometric 

growth trends caused by the narrowing of rings as stem diameter increases. If a step change in growth was observed, a 

second detrending was done using a two-thirds spline to

remove increases in growth related to changes in local competition (Lorimer and Frelich 1989). Standardized ring widths 

were then averaged to create an index of growth for each 

site. 

Chronology signal strength was characterized using series 

intercorrelation (SNC) and the between tree expressed 

population signal (EPS). SNC indicates the strength of the 

common signal within a sample population and is derived 

from the correlation between all time-series of growth. EPS is 

a function of the mean correlation of all growth series within 

a population and sample size (Wigley and others 1984). It 

describes how well a finite sample size estimates the infinite, 

hypothetical population. These statistics are among the most

commonly used indicators of agreement in year-to-year growth

among trees within a population (Cook and Kairiukstis 1990).

The climatic sensitivity of each population was found by 

correlating the standardized ring index chronology against 

mean monthly temperature and total monthly precipitation 

from prior March to October of the current growth year. We 

chose a 20-month period of climate for correlation analysis 

as climate of the prior year can influence ring width of the 

current year (Fritts 1976). Because long-term meteorological 

records of minimum and maximum temperatures are lacking 

in the Appleton Bog region of ME, we chose to use gridded 

meteorological data from the Climatic Research Unit (CRU) 

of the University of East Anglia, UK (Jones 1994, New and 

others 2000). Grid points are located every 0.5 degrees and 

are interpolated climatic data from the eight nearest stations. 

For our purposes, data from the grid point closest to the 

sample site was used. Data is available from 1901 to 1995. 

Correlations were considered significant at p < 0.05 unless 

otherwise stated.

Regional Temperature and Growth Trends

To test if the climate signal in AWC is potentially regional, 

we compared a time-series of regional temperatures with a 

time-series of regional growth. Using CRU data, the months 

of temperature most commonly correlated to growth (prior 

May and June, prior November though current May and 

current July and August) were averaged using a mean and 

variance corrected arithmetic average procedure. This timeseries covers 1902 to 1995 because 1 year is lost due to the 

combination of months from the prior and current years (e.g. 

May, June, November and December 1901 combined with 

January to May and July and August 1902). An arithmetic 

average was made of the standardized chronology of each 

population to create the regional time-series of growth. 

RESULTS

Appleton Bog, ME

Appleton Bog is unique in that it is the northernmost known 

stand of AWC (Stockwell 1999). The forest floor is covered 

with Sphagnum moss and fern species. AWC dominates the

canopy, comprising 77.3 percent of the basal area (BA), with

occasional red maple [Acer rubrum L. (13.6 percent)] and black

spruce [Picea mariana Mill. (12.5 percent)] present. Maximum

tree age was 141 years with more than one-half of the trees 

older than 119 years (table 2). The SNC was r = 0.616, which

is well above the 99 percent confidence level of 0.328 (Holmes

1983). EPS value for the Appleton Bog chronology was 0.929,

which is above the accepted level of 0.85 (Wigley and others 

1984). The standardized ring index chronology showed below 

average growth in the early 1920s and 1960s while above 

average growth occurred in the mid-1920s through the mid1950s and from the mid-1970s until the mid-1990s (fig. 2A). 

Appleton Bog AWC was positively correlated with temperature during the prior May, June, September, November, 

and current January through April (table 3). These months 

accounted for 29.6 percent of the ring width variations. Only 

3 months show positive correlation with precipitation: prior 

August, current March and July accounted for 8.80 percent of 

the growth variation.

Table 1—Site information for the Atlantic white cedar stands sampled

 Stand BA

Site County Latitude/longitude Elevation (STD)

m m2

/ha

Appleton Bog, ME Knox N43°33’ W70°28’ 120 66.0 (15.3)

Saco Heath, ME York N44°20’ W69°16’ 40 35.5 (24.0)

Westminster, MA Worcester N42°32’ W71°57’ 250 47.3 (22.8)

Monson, MA Hampden N42°03’ W72°18’ 260 48.0 ( 6.9)

Madison, CT New Haven N41°21’ W72°38’ 80 —

High Point, NJ Sussex N41°38’ W74°39’ 460 54.8 (17.9)

Uttertown, NJ Passaic N41°10’ W74°25’ 300 79.2 (15.7)

BA = basal area.
25

Table 2—Statistical characteristics of the final Atlantic white-cedar chronologiesa 

 Date when 

 Number of sample 

 Median samples depth = 

Site Trees Cores Interval ageb Rbar EPS EPS = 0.85 0.85 EPSc

 - - - number - - - years min/max 

Appleton Bog, ME 21 29 1862 – 2002 119 (63/141) 0.375 0.929 10 1879

Saco Heath, ME 20 30 1874 – 2002 100 (69/129) 0.583 0.933 5 1879

Westminster, MA 26 29 1859 – 2002 111 (82/200) 0.378 0.922 10 1887

Monson, MA 16 17 1865 – 2002 116 (53/138) 0.531 0.926 5 1870

Madison, CT 21 22 1819 – 1992 142 (92/174) 0.608 0.974 4 1831

High Point, NJ 20 31 1807 – 2002 150 (104/196) 0.393 0.936 9 1830

Uttertown, NJ 20 20 1762 – 2002 125 (72/242) 0.257 0.863 17 1897

EPS = expressed population signal.

a

 Rbar is the average correlation between all trees. EPS is the expressed population signal. See text for more details.

b Tree ages are likely higher than shown since several sites had some rot, especially Westminster, MA and High Point, NJ.

c This column refers to the date when the sample depth equals the number of cores required to reach an EPS value of 0.85 for each chronology. 

Before this date, sample depth declines and it is expected that the EPS value would drop below 0.85.

Figure 2—Standardized radial growth chronologies for: (a) Maine (b) Massachusetts (c) Connecticut, and (d) New Jersey. See text for 

details of each site within each State. Growth is standardized about a dimensionless index of one represented by the horizontal flat line.

YEAR

Radial Growth Index

c

a

b

d

Radial Growth Index

c

a

b

Radial Growth Index

YEAR

Radial Growth Index

c

a

b

d

Saco Heath, ME

Saco Heath is the only known domed-bog to support AWC 

(Laderman 1989). Saco Heath is composed of scattered 

aggregations of trees through out a dense shrub layer dominated by blueberry (Vaccinium spp. L.). In the forested areas, 

AWC is the dominant tree comprising 82.9 percent of the 

BA, while white pine (Pinus strobus L.) is present to a lesser 

extent at 12.7 percent. Maximum tree age at Saco Heath 

was 129 years with more than one-half of the trees older 

than 100 years (table 2). The SNC was r = 0.567 while the 

EPS was 0.933. The ring index chronology had growth trends 

similar to Appleton Bog. The early 1920s and 1960s were 

a decade of below average growth (fig. 2A). The low growth 

in the 1960s was followed by a period of unprecedented 

above-average growth that lasted to the present. March to 

August and November to December temperatures of the 

previous growing season, and January to February and April 

to August temperatures of the current growing season were 

positively correlated with growth (table 3) and accounted 
26

for 44.46 percent of the annual growth variation. Growth at 

Saco Heath was also positively correlated to mean monthly 

precipitation data for August and November of the previous 

growing season, and March to April and August of the 

current growing season. These months accounted for 27.68 

percent of the growth variation.

Westminster, MA

The Westminster forest is comprised of AWC (60.3 percent 

BA), tamarack [Larix laricina (Du Roi) K.Koch (38.1 percent)], 

red maple (16.9 percent), and red spruce [Picea rubens Sarg.

(14.8 percent)]. Maximum tree age in this population was 

200 years with more than one-half of the trees older than 111 

years (table 2). The SNC was r = 0.565 while the EPS was 

0.922. Radial growth was generally below the average value 

between the 1900s and the mid-1950s (fig. 2B) and above 

the average value after the 1950s. Growth of the Westminster 

population was positively correlated to the previous year’s 

May to June, September, and November temperatures, as well

as current March, May, August, and September temperatures 

(table 3). Growth was positively correlated with precipitation 

of the current July and September. Temperature accounted 

for 30.54 percent of ring width variation, while precipitation 

accounted for 11.23 percent.

Monson, MA

At Monson, AWC comprises 42.2 percent of the BA, with 25.0

percent red spruce, 25.0 percent eastern hemlock (Tsuga 

canadensis L.), 18.8 percent eastern white pine (Pinus 

strobus L.), and 16.7 percent red maple. Monson has field 

evidence of logging within the last 70 years. Maximum tree age

at Monson was 138 years with more than one-half of the 

trees older than 116 years (table 2). The SNC was r = 0.622 

while the EPS was 0.926. Radial growth was generally below

average growth from the 1900s to the mid-1950s (fig. 2B). 

The radial growth index showed a period of decreasing ring

width from the 1890s to the early 1920s. Growth from 1970 

through the mid-1980s was above average and has since 

decreased considerably. Growth in the Monson AWC popu

-

lation was positively correlated to the prior year’s March, 

September, November and current February temperatures 

(table 3) and accounted for 16.37 percent of the ring width 

variations. Only a wet prior November was correlated to growth

and accounted for 4.02 percent of the annual growth variation.

North Madison Cedar Swamp, CT

The North Madison Cedar Swamp is a late-successional 

bog-forest dominated by AWC, with scattered red maple 

(Andrews and Siccama 1995). Maximum tree age in the 

North Madison Cedar Swamp was 174 years with more than 

one-half of the trees older than 142 years (table 2). The SNC 

was r = 0.616 while the EPS was extremely high at 0.974. 

Radial growth was below average from the 1840s through 

the early 1920s, after which growth was above average except

for a dip in the 1960s (fig. 2C). Growth in the North Madison 

AWC population was positively correlated to prior May to July 

and December, and current February to July temperatures

(table 3). These months accounted for 19.49 percent of annual

growth variations. A wet current October was positively correlated to growth accounting for 5.71 percent variance in ring 

width. 

Table 3—Significant correlation between Atlantic white cedar growth and mean monthly temperatures

Site M A M J J A S O N D J F M A M J J A S OAppleton Bog, ME ** ** ** * ** * * * Saco Heath, ME ** *** ** * ** * ** ** *** *** ** ** * ** *** Westminster, MA   **  ** * * * * Monson, MA ** * * * Madison, CT ** ** * * * * * * * * High Point, NJ * ** *** * * *** ** * *** Uttertown, NJ * * ** * 

Number of sites  with significant  correlation 1 2 6 4 2 2 3 0 5 4 3 5 4 5 3 2 3 3 1 0* = a significant relation between 0.01< and < 0.05; ** = significance between 0.001< and < 0.01; *** = significance between < 0.001.
27

High Point State Park, NJ

High Point’s AWC population is growing at the highest 

recorded elevation for the species (Laderman 1989). AWC 

makes up 73.9 percent of the total BA with eastern hemlock 

(13.7 percent) and red maple (10.9 percent) as the next most 

dominant trees. Maximum tree age in the High Point was 

196 years with more than one-half of the trees older than 

150 years (table 2). Several of these trees were hollow, and 

this prevented analysis of growth in older wood. Hence, age 

structure is a bit older than what can be reported here. The 

SNC was r = 0.549 while the EPS was 0.936. The standardized chronology shows a decline in ring width from the 1850s 

until the 1950s, after which ring width was above average 

(fig. 2D). This population was very sensitive to temperature

(table 3), and growth was positively correlated to prior April,

August, November, December, and current January, February,

April, July and August. Temperature accounted for 37.54 

percent of the ring width variation. Only 2 months, May and 

November of the prior growing year was positively correlated 

with precipitation and accounted for 11.43 percent of the ring 

width variation. 

Uttertown Bog, NJ

Uttertown Bog is one of New Jersey’s few remaining peatlands (Kuo 2003). AWC represents 80.3 percent of the BA, 

with eastern hemlock representing 18.0 percent. Maximum 

tree age in Uttertown Bog was 242 years with a majority of

the trees between 110 and 140 years old (table 2). The SNC

was r = 0.566 while the EPS was only 0.863. Radial growth

increased from the 1860s until the 1910s, followed by a period

of decline until the 1950s (fig. 2D). Following a slight dip in 

the 1960s, growth has increased since the 1970s. Uttertown 

was one of the least climate-sensitive populations studied 

here. Prior April and December and current January and April

temperatures were positively and significantly correlated to 

climate (table 3) accounting for only 10.07 percent of the ring 

width variation. Prior May and December and current May 

and June precipitation were significant and positively correlated to growth. Precipitation accounted for 13.88 percent of 

the variation in ring width.

Regional Temperature and Growth Trends

There was a strong agreement between regional temperature and AWC growth (r = 0.66; p < 0.0001) from 1902 to

1995 with temperature accounting for 42.9 percent of 

variation in growth. The agreement is especially evident at 

decadal time scales (fig. 3). 

DISCUSSION

Usefulness of AWC for Dendrochronology 

Our results show that AWC growth is very sensitive to environmental conditions, making it useful for tree-ring analysis. 

The between-tree EPS was high (> 0.920) in six of the seven 

populations and suggests a strong common signal. Though 

not the focus of this study, individual trees from several populations showed possible release from competition that was 

likely related to canopy disturbance. Standard disturbance 

detection methods may be used to reconstruct stand history 

using AWC (Lorimer and Frelich 1989). 

The primary limitation for the dendroclimatological use of 

AWC at the sites studied is its current age structure. Most 

stands sampled were < 130 years in age. The Uttertown site 

appears to be essentially an even-aged 120 year-old forest 

with a few scattered old trees. North Madison, CT and High 

Point sites had the least disturbed forests of the sites studied 

and yet no trees older than 200 years were found. If available,

sub-fossil or relict wood samples could be analyzed in an 

attempt to extend stand disturbance history and chronology 

length. Given AWC’s responsiveness to environmental variation, it is likely worth the effort and expense of relict wood 

recovery. Such a collection would greatly enhance our knowledge of long-term climate variability and AWC ecology in a 

heavily populated region, which may be useful for restoration 

of AWC ecosystems.

Climate Response

In general, AWC has a positive correlation to temperature at 

its northern range limit (fig. 4). Across all sites the monthly 

temperatures most frequently correlated with growth were 

prior May and June, prior winter through current spring 

(November to May), and current July and August temperatures (table 3). The strongest correlations between growth 

and temperature were during winter months. More than onehalf of the sites sampled had levels of temperature sensitivity 

similar to the trees used for the only Eastern United States 

temperature reconstruction (Conkey 1982). Temperature 

accounted for 29.6 percent or more of annual growth variation at four sites making AWC one of the most temperature 

sensitive trees in the Eastern United States. 

Of the sites sampled, correlations were strongest at Saco 

Heath, Appleton Bog, and Westminster Swamp, indicating 

that temperature is most important near the northernmost end

of AWC’s range limit. More southerly populations at North 

Madison and Uttertown had a lower sensitivity to temperature variation. These results are similar to the temperature 

Figure 3—Regional temperatures (solid line) versus regional 

standardized growth of Atlantic white cedar (dashed line with solid 

diamond symbols). See text for further details.
28

sensitivity for growth documented previously for loblolly pine 

(Cook and others 1998).

High Point, NJ is an exception to the geographic trend in 

temperature sensitivity. While High Point was one of the more 

southern sites sampled, AWC growth was one of the most 

sensitive to climate, but this population is growing at the highest known elevation for the species and likely experiences 

lower temperatures than other populations at that latitude. 

Using the CRU meteorological data, mean annual winter and 

summer temperatures from 1901 to 1995 for High Point fall 

close to those for Saco Heath, ME. Average summer and 

winter temperatures at High Point are 21.06 °C and -1.66 °C,

respectively. At Saco Heath summer and winter temperatures

averaged 20.06 °C and -3.66 °C. However, there is a significant difference between the elevation of the High Point AWC

population (460 m) and the closest meteorological station 

most likely to have been heavily weighted in the CRU interpolation data (Point Jervis, NY, 143 m). Assuming an average 

environmental lapse rate of 0.65 °C cooling per 100 m in 

elevation, the mean summer and winter temperatures at 

High Point would actually be roughly 19.00 °C and -3.72 °C, 

respectively. Thus, the temperatures in which the High Point 

AWC trees live would fall within the range of temperatures 

of the Maine AWC sites, possibly explaining the exception in 

the geographic trend.

If AWC responds like other tree species, the reduced temperature sensitivity of populations at more southern sites may be

the result of location in the species’ range (Cook and others 

1998) or greater competition with other plants (Cescatti and 

Piutti 1998). The current age structure at the Monson site 

suggests stands are still in the stem exclusion stage during 

which competition induces self-thinning and excludes tree 

recruitment (Oliver and Larson 1996). As a result, stand 

development at Monson may be contributing to AWC’s 

reduced temperature sensitivity at this site.

The Uttertown site was the only site where growth was more

sensitive to precipitation than temperature. Also, it was the

southernmost site sampled. In addition to a warmer climate 

than experienced by the more northern populations, increased

competition may cause tree growth to be more limited by precipitation as was shown in another tree species by Cescatti 

and Piutti (1998). While the Uttertown site has the highest 

estimated BA of the sites sampled, it is similar to the BA of 

Appleton Bog, near the species’ northern range limit. More 

work is needed to determine if stand densities (a proxy for 

competition) within one climate region has an influence on 

AWC’s climate sensitivity.

It is interesting to note sites that showed the highest sensitivity to temperature also showed the highest sensitivity to 

precipitation (fig. 4). The Saco Heath population showed the 

greatest overall sensitivity to climate. Since Saco Heath is 

a domed-bog, a unique wetland type for AWC (Laderman 

1989), perhaps the site’s physical characteristics along with 

its range position made it the most sensitive to climate. A 

domed-bog results from the build up of peat over time, which 

eventually serves to elevate the area from its surroundings 

so that it is perched above the water table. Surface water 

does not drain into domed bogs, making precipitation the 

primary source of water. The physical structure of a domed 

bog and the resulting hydrological regime would seem to 

explain Saco Heath’s high sensitivity to precipitation. Saco 

Heath’s low stand density (table 1) could also have been a 

factor in the high temperature sensitivity, following the same 

logic in the previous paragraph. 

Growth Trends

Most sites showed similar decadal variations in growth over 

the last century, especially over the last 30 years indicating a 

growth trend for the region (figs. 2 and 3). The recent period 

of common increased radial growth suggests large-scale 

influences on growth, such as climate, nitrogen deposition 

or elevated CO2

. Temperature seems the most plausible 

0%

5%

10%

15%

20%

25%

30%

35%

40%

45%

Saco Heath,

ME

High Point, NJ Westminster,

MA

Appleton

Bog, ME

N.Madison,

CT

Monson, MA Uttertown,

NJ

Sample Sites

Temperature

Precipitation

Percent

Figure 4—Sites are listed from left to right in the order of decreasing temperature 

sensitivity. The y-axis represents the amount of annual ring width variation that can 

be accounted for (r-squared) by temperature (open bars) and precipitation (black 

bars). See text for further details.
29

explanation for much of the last 100 years. A decline in 

regional growth trends during the 1960s (fig. 3) in concert 

with declines in regional and global temperatures (Jones 

and Moberg 2003) suggest temperature is controlling radial 

growth. In fact, the CRU meteorological data for our study 

region and Northern Hemisphere data show that winter 

and spring temperatures have been rising over the recent 

decades (Jones and Moberg 2003, Lugina and others 2003) 

suggesting temperature may be linked to increased radial 

growth in recent decades. 

Minimum temperatures have increased more rapidly than 

maximum temperatures (Karl and others 1993), which may 

be an important attributing factor to the increasing growth 

trend. AWC research of populations in the southern New 

York State and northern New Jersey region suggests growth 

is consistently correlated with minimum July and August 

temperatures (Pederson and others 2004). To date, we don’t 

know if this local sensitivity to growing-season minimum 

temperature occurs at the regional scale as well.

The Monson site remained the exception to general regional 

patterns, and had a sharp decline in growth over the last 15 

years. The lack of synchronicity in the Monson population may

again be attributed to its disturbance history or inadequate 

sampling for detection of trends. 

CONCLUSION

Atlantic white cedar growth is sensitive to changes in its environment. All populations tested showed strong interseries

correlation and EPS values, indicating that the trees are 

responding to a common signal in their environment. More 

importantly radial growth in AWC at its northern range limit was

positively correlated with monthly mean temperature data 

over the prior and current year. Atlantic white cedar growth 

also was positively correlated with variations in monthly mean

precipitation data, but correlations were not as strong. The 

sites most sensitive to temperature were also found most 

sensitive to precipitation. 

The forecast of future climatic warming does not appear to 

pose any immediate threat to growth of this species along 

its northern range limit. If temperature trends proceed as 

expected increasing 1.7 to 4.9 °C over the next century 

(IPCC 2001, Wigley and Raper 2001), growth would likely 

increase assuming moisture availability does not become a 

more important limiting factor. This could have implications 

for future ecosystem management and carbon sequestration 

modeling. However, how climate change will influence relative competitive ability is unknown. 

ACKNOWLEDGMENTS

Fellowship provided to NP by the U.S. Department of Energy

Global Change Education Program. We would like to thank:

Susan Ask [Maine Chapter of The Nature Conservancy 

MTNC)], Glen Colburn (Monson Cedar Swamp Conservancy),

Dr. Rosanne D’Arrigo [Lamont-Doherty Tree Ring Lab (TRL)], 

Nicole Davi (TRL), Dr. Aimlee Laderman (Yale University), 

Dr. Les Lynn (Uttertown Bog), John Keator [High Point State 

Park (HPSP) supervisor], Erika Mashig (TRL), Kate Monihan 

(HPSP), Glen Motzkin [Harvard Forest (HF)], Dr. Dave Orwig

(HF), Dee and Calla Pederson (Columbia Univerity), Charles

Pernaa (MA Dept. of Environmental Management), Parker 

Schuerman (MTNC), Dr. Thomas Siccama and his Yale 

Forestry students, and Nancy Sferra (MTNC). This is LamontDoherty Earth Observatory contribution number 6661.

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31

INTRODUCTION

Atlantic white-cedar [Chamaecyparis thyoides (L.) BSP] populations have decreased in number and size since colonial 

times, a pattern that has generated much concern for cedar 

conservation (Laderman and others 1987, Motzkin 1990, 

Mylecraine and Zimmermann 2000, Sperduto and Ritter 1994).

Some of this loss has been attributed to inadequate recruitment under a closed canopy and subsequent successional 

change (Hickman and Neuhauser 1977, Korstian and Brush

1931, Little 1950, Motzkin 1990, Stoltzfus and Good 1998).

However, a closed cedar canopy may not be the primary 

limiting factor to cedar establishment (Kuser and Zimmermann

1995). In fact, there are conflicting reports concerning the

shade tolerance of Atlantic white-cedar (Hickman and 

Neuhauser 1977, Korstian and Brush 1931, Little 1950, 

Motzkin 1990, Stoltzfus and Good 1998). Other potentially 

limiting factors, including microtopography, soil moisture, and 

substrate may better explain the lack of successful cedar 

recruitment in some wetlands (Allison and Ehrenfeld 1999, 

Ehrenfeld 1995a).

As remaining populations of cedar are confined to public and

private conservation lands, the decline of cedar due to inadequate seedling recruitment has become a management concern (Allison and Ehrenfeld 1999, Kuser and Zimmermann 

1995, Motzkin 1990, Mylecraine and Zimmermann 2000). In 

fact, recently there has been interest in cedar’s recruitment 

requirements and techniques for regenerating and restoring 

cedar populations (Ehrenfeld 1995b, Kuser and Zimmermann 

1995, Mylecraine and Zimmermann 2000). There is still uncertainty in the habitat requirements for successful restoration. 

Typically, natural Atlantic white-cedar swamps are defined by 

a network of elevated hummocks and frequently water-filled

depressions or hollows (Ehrenfeld 1995a, Stoltzfus and Good

1998). Cedar commonly occurs on hummocks and it has been

suggested that hummock microtopography, as it affects moisture availability, may be an important factor explaining how 

cedar seedling distribution occurs on hummocks (Ehrenfeld 

1995a, 1995b). According to Ehrenfeld (1995b), cedar seedlings were most common at intermediate elevations on hummocks, avoiding the lowest and highest elevations. Perhaps 

seedling recruitment is unsuccessful at the top of hummocks 

and at the lowest elevations in the hollows because of drought

and prolonged flooding respectively (Mylecraine and Zimmermann 2000). Moisture is considered one of the critical factors 

for Atlantic white-cedar regeneration (Laderman 1989, Little 

1950). Both excessive and insufficient moisture may prevent 

germination and seedling growth (Kuser and Zimmermann 

1995). According to Little (1950), moisture conditions were 

optimal for seedling growth if the water table was within 

13 cm of the ground surface. In a more recent greenhouse 

experiment, growth of cedar seedlings was greatest in moist, 

drained soil; was intermediate in saturated soil; and least in 

inundated soil conditions (Allison and Ehrenfeld 1999).

In addition, Atlantic white-cedar recruitment is affected by the

understory light regime (Little 1950). While cedar’s shade

tolerance is debated in the literature (Hickman and Neuhauser

1977, Motzkin 1990, Stoltzfus and Good 1998), Little (1950)

observed a strong decline in cedar seedling survival when 

seedlings were beneath the heavy shade of a closed canopy.

Other studies indicated that open seed beds free of competing vegetation are necessary for cedar establishment (Buell 

and Cain 1943, Korstian and Brush 1931).

The frequency of occurrence and growth of cedar seedlings 

is greater in organic peat soils, i.e., histosols with moss and 

DISTRIBUTION OF ATLANTIC WHITE-CEDAR

SEEDLINGS IN A NEW HAMPSHIRE SWAMP:

ASSOCIATION WITH MICROSITE CHARACTERISTICS

Lara M. Gengarelly and Thomas D. Lee1

1 Lara M. Gengarelly, Lecturer, University of New Hampshire, Department of Education, Durham, NH 03824; and Thomas D. Lee, Associate 

Professor of Forest Ecology, University of New Hampshire, Department of Natural Resources, Durham, NH 03824.

Citation for proceedings: Burke, Marianne, K.; Sheridan, Philip, eds. 2005. Atlantic white cedar: ecology, restoration, and management: 

Proceedings of the Arlington Echo symposium. Gen. Tech. Rep. SRS-91. Asheville, NC: U.S. Department of Agriculture, Forest Service, 

Southern Research Station. 74 p.

Abstract—The distribution pattern of Atlantic white-cedar seedlings was studied at Brown Mill Pond in Rye, NH, in order to 

identify which biological or physical factors were associated with seedling presence. Seedlings occurred on hummocks that 

rose above the water-filled hollows. However, some hummocks lacked seedlings and most others were only partly covered 

by seedlings. We chose 171 20 by 20 cm plots in which seedlings were surveyed as either present, absent (not present 

anywhere on the hummock), or missing (not present in the plot, but present elsewhere on the hummock). Elevation relative to 

the water table, percent canopy cover, substrate type, herb and shrub density, and distance to nearest probable parent tree 

were measured in each plot. To determine if seedling presence and absence could be predicted from the measured environmental variables, a standard discriminant function analysis was performed and explained 86 percent of the variance in cedar 

distribution. The most discriminating factors in explaining seedling presence were (1) moss-litter substrate rather than tussock 

sedge peat substrate, and (2) elevation within 30 cm of the water table.

Keywords: Atlantic white-cedar, environmental variables, New Hampshire, seedling distribution, substrate type, water table. 
32

litter substrate compared to other substrates (Allison and 

Ehrenfeld 1999, Laderman 1989, Little 1950) However, Haas 

and Kuser (1999) established cedar seedlings on a sandy 

mineral soil. These conflicting results illustrate that there is 

still uncertainty in our understanding of cedar germination 

and seedling establishment requirements with regard to 

substrate.

The objective of this research was to identify which biological 

or physical conditions were associated with Atlantic whitecedar seedling presence at Brown Mill Pond in Rye, NH. 

More specifically, this study investigated the presence and 

absence of seedlings among microsites in relation to elevation above the water table, percent canopy cover, hummock 

substrate type, shrub density, and distance to nearest probable parent tree.

METHODS

This study was conducted during the summer of 2000 in a 

Nature Conservancy-owned cedar wetland at Brown Mill 

Pond in Rye (Rockingham County), NH. The soils have 

been classified as a Chocorua mucky peat and hummockhollow microtopography is well-developed (Kelsea and Gove 

1994). The average difference between hummock tops and 

hollows was 52 cm + 7, with a maximum difference of 85 

cm (Gengarelly 1999). Cedar dominates some areas of this 

45 ha wetland while in others it mixes with Acer rubrum L. 

(red maple), Tsuga canadensis (L.) Carr. (eastern hemlock), 

and Picea rubens Sarg. (red spruce). In previous fieldwork 

(Gengarelly 1999), the site was divided into five communities 

or stands based on tree species composition, cedar diameter, and cedar height.

The field survey of seedlings was conducted in the pond edge

community, which borders Brown Mill Pond and its tributary, 

Bailey Brook (Gengarelly 1999). This area was selected 

because it was characterized by an uneven-aged cedar 

stand with continuous cedar establishment, a discontinuous 

cedar-red maple canopy and the highest water table on the 

study site (Gengarelly 1999). Two types of hummocks were 

present, categorized by the dominant surface ground cover 

(substrates). Tussock sedge hummocks were characterized 

by a tussock sedge (Carex stricta Lam.) substrate consisting 

of a network of vertical rhizomes intertwined with fine roots 

and decomposing organics, such as leaf litter (Lord and Lee 

2001). Moss-litter hummocks were characterized by a carpet 

of mosses, including Sphagnum spp., Dicranum spp., and 

other taxa, and areas lacking mosses; i.e., litter-covered 

substrate). Moss-litter covered hummocks are commonly 

described in other cedar wetlands, especially in New Jersey, 

and are referred to simply as peat hummocks (Ehrenfeld 

1995a).

The sampling design included thirteen transects (~ 15 m in 

length), randomly located in the pond edge community such 

that they extended perpendicular to and away from the pond 

and brook. Hollows were not sampled because seedlings were

never found in them. All hummocks with surfaces > 15 cm in

elevation above the water level and within 2 m of either side

of the transect were mapped, numbered, characterized for

substrate type, surveyed for cedar seedlings, and the area was

measured. Hummock area was determined by measuring the 

length and width of a hummock and using the ellipse formula 

(Area = π Length*Width/4). Any cedar displaying some scalelike foliage (suggesting that seedlings were at least in their 

second growing season) and a height between 5 and 30 cm 

was considered a seedling. The number of seedlings and 

substrate type was recorded for each hummock.

Along each transect approximately 15 randomly located 20 

by 20 cm plots were established on the mapped hummocks. 

Plots fell into one of three categories: (1) seedling absent, 

(2) seedling missing, and (3) seedling present. New random 

locations on hummocks were generated until an equal 

number of plots of each type was sampled. Seedling absent 

plots were situated on hummocks that did not contain cedar 

seedlings. Seedling missing plots, while not containing any 

seedlings, were located on hummocks that supported seedlings elsewhere. All seedling missing plots were a minimum 

of 30 cm from any cedar seedling. Seedling present plots 

contained at least three cedar seedlings. Plots with one 

or two seedlings were omitted. In the end, 57 of each type 

of sampling plot; i.e., absent, missing, or present were 

observed.

Microsite Characteristics 

Within each plot, selected environmental variables were 

measured. Percent cover of substrate types—tussock sedge, 

leaf litter, moss—was determined by projecting 100 dots over 

the 20 by 20 cm plot and recording the substrate intercepted 

by each dot. Densities of all herbaceous and shrub species 

were measured. In order to determine elevation, the vertical 

distance from the center of the plot to the water table was 

measured using a line level and meter stick. Elevations were 

adjusted to a single water table height in July (July 3, 2000). 

Thus, the July 2000 water table was used as the reference 

elevation. Percent open canopy was quantified using a digital 

camera with a fish-eye lens and images were processed with 

Gap Light Analyzer (Frazer and others 1999). Parent tree 

proximity was the mean distance between the center of the 

plot and the two closest reproductive adult cedars.

Statistical Analysis 

In order to determine if plots with cedar seedlings, without 

seedlings, and missing seedlings could be predicted from the 

measured environmental variables, a standard discriminant 

function analysis was performed; i.e., all predictors entered in

one step. The analysis was performed with SPSS 9.0 for PC

(Norusis 1999). The seven predictor variables were: (1) elevation relative to the water table, (2) percent open canopy, 

(3) percent moss substrate, (4) percent leaf litter substrate, 

(5) percent tussock sedge substrate, (6) herbaceous and 

shrub density, and (7) distance to nearest probable parent. 

Three seedling groups were tested, with group membership 

established prior to the analysis and based on seedling plot 

type. Group 1 consisted of the seedling present plots (n = 57),

group 2 consisted of the seedling missing plots (n = 57), and 

group 3 consisted of seedling absent plots (n = 57).

A standard multiple regression was performed between 

cedar seedling number per hummock as the dependent variable and hummock substrate type (tussock sedge vs. mosslitter), hummock area, and the appropriate interaction term; 

i.e., substrate type x area, as independent variables. In order 

to improve the normality and linearity of the residuals, square 
33

root transformations were used on the seedling number and 

hummock area measures. This analysis was made using 

SYSTAT 5.2 for PC (Wilkinson and others 1992).

RESULTS

Discriminant Function Analysis

The three seedling groups—present, absent, missing—

differed in their relationship with the environmental variables as

described by the discriminant functions. As there were three 

groups (seedling present, seedling missing, and seedling 

absent) two discriminant functions were created in this analysis. Together, these discrimant functions successfully explained

86 percent of the variance in the discriminant scores. Furthermore, each discriminant function alone explained a significant

proportion of the variance in the discriminant scores (rc = 0.85

and 0.70, respectively, p < 0.001). 

The first discriminant function (DF1) discriminated among 

seedling distribution class based on plot substrate type: 

seedling-absent plots occurred most often on hummocks 

with tussock sedge substrate while the other two kinds of 

plots occurred most often on hummocks with either moss 

or litter substrate. High scores on DF1 were associated with 

both tussock sedge substrate (table 1) and the seedling 

absent group (fig. 1). Low scores were associated with moss 

or litter substrate (table 1) and both the seedling present and 

seedling missing groups (fig. 1). The second discriminant 

function (DF2) showed that on hummocks with moss-litter 

substrate, seedlings were more likely to be found at elevations within 30 cm of the water table than at higher elevations 

(table 1). High scores on this function were associated with 

greater elevations while low scores were associated with 

lower elevations. Points with high scores on DF2 and thus 

high scores on elevation were predicted to be in the seedling 

missing group (fig. 1).

The discriminant analysis results were confirmed with univariate one-way analyses of variance (ANOVA) that tested each 

substrate variable across all three seedling groups (table 2).

Seedling absent plots had significantly greater percent tussock substrate (mean = 76 percent) than either seedling 

present plots (mean = 3 percent) or seedling missing plots 

(mean = 3 percent) and mean percent cover of both moss 

and litter substrate were significantly lower for the seedling 

absent group than for the other seedling groups (table 2).

Univariate tests also confirmed that elevation was a predictor 

of seedling presence at Brown Mill Pond. The mean elevation 

of seedling missing plots was significantly greater (mean = 

33.9 cm) than the elevations of the seedling present (mean =

17.6 cm) or seedling absent plots (mean = 19.0 cm) (table 2).

A larger number of plots with cedar seedlings was located at

low to intermediate elevations (10 to 25 cm) than at either the

lowest (< 5 cm) or highest (> 30 cm) elevations on hummocks

with moss-litter substrate (fig. 2A). While plots were less 

common at elevations < 10 cm, all four of these plots 

contained cedar seedlings (fig. 2B).

Regression Analysis 

Only one of the independent variables contributed significantly to prediction of number of seedlings per hummock. 

Specifically, square root of hummock area had a standardized regression coefficient that differed significantly from zero 

(Beta = 0.68, t = 2.15, p = 0.03) (table 3) while coefficients 

associated with substrate type and the interaction did not 

differ significantly from zero (p > 0.05) (table 3). Mean area 

of moss-litter hummocks was 1.104 m2

, while mean area of 

tussock sedge hummocks was 0.349 m2.

Table 1—Discriminant function analysis of seedling 

presencea 

 

Standardized canonical

discriminant function 

Predictor coefficients

variable Function 1 Function 2

Elevation relative to 

 water table (cm) 0.170 0.958

Open canopy (percent) 0.016 -0.099

Moss substrate (percent) -0.471 -0.251

Litter substrate (percent) -0.482 0.103

Tussock substrate (percent) 0.378 0.043

Herb and shrub density 0.254 0.109

Distance to nearest 

 parent tree (cm) 0.356 0.180

a Results of discriminant function analysis that predicted Atlantic 

white-cedar seedling groups (seedling present, seedling absent, 

seedling missing) at Brown Mill Pond, Rye, New Hampshire, based 

on several environmental predictor variables (July 2000). The 

standardized canonical discriminant function coefficients for each 

predictor variable and each discriminant function are presented.

Figure 1—Discriminant function analysis testing predictability of 

Atlantic white-cedar seedling groups (seedling present, seedling 

absent, seedling missing) at Brown Mill Pond, Rye, NH based on 

several environmental variables (July 2000). Discriminant axes 

scores for all plots in each membership group (n = 57). The x-axis 

represents scores on discriminant function one. The y-axis represents scores on discriminant function two. Italicized labels indicate 

the predictor variable most strongly related to low or high scores on 

each function.

Present plots

Missing plots

Absent plots
34

DISCUSSION

Cedar seedling distribution was not random at Brown Mill 

Pond. Seedlings were absent from hummocks with tussock 

sedge substrate and present on hummocks with some alternative substrate such as moss or leaf litter. On the moss-litter 

hummocks, seedlings were present most often 10 to 25 cm 

above the water table and missing from the highest elevations (> 30 cm).

Substrate Type

In agreement with the work by Allison and Ehrenfeld (1999) 

cedar seedlings in this study appeared to prefer a peatbased substrate with overlying moss or litter more than a 

graminoid-based substrate with overlying sedge and grass. 

Historically, organic peat has been considered a suitable site 

for cedar seedlings (Little 1950) but few seedling surveys 

have addressed the distribution of established seedlings 

Table 2—Mean differences in predictors among seedling presence classesa

 Classification group mean

Seedling Seedling Seedling 

Predictor present missing absent 

variable (n = 57) (n = 57) (n = 57) F p

Elevation 

relative to 17.61a 33.91b 19.01a

water table (cm) (5.30) (8.47) (9.32) 74.77 < 0.001

Open canopy 10.39a 8.28b 11.71a

(percent) (3.32) (2.38) (3.78) 16.49 < 0.001

Moss substrate 35.14a 20.21b 2.25c

(percent) (26.89) (24.04) (6.14) 34.66 < 0.001

Litter substrate 47.26a 74.79b 10.96c

(percent) (30.26) (28.44) (28.47) 69.11 < 0.001

Tussock substrate 3.32a 3.53a 76.33b

(percent) (17.35) (15.98) (38.15) 150.59 < 0.001

Herb and shrub 2.93a 4.46a 51.11b

density (6.53) (9.08) (38.11) 81.29 < 0.001

Distance to nearest 64.61a 82.55a 203.02b

parent tree (cm) (59.31) (101.55) (102.39) 39.84 < 0.001

aThe group mean for each predictor variable used in a standard discriminant analysis that 

tested the predictability of Atlantic white-cedar seedling group membership at Brown Mill Pond, 

Rye, New Hampshire (July 2000). Standard deviations are reported in parentheses. F and p 

values are for the main effect of one-way analyses of variance comparing a predictor variable 

across all 3 seedling classification groups. Means with the same letter are not significantly 

different according to a Tukey’s multiple comparison test (p < 0.05).

Table 3—Multiple regression of hummock area and substrate typea

Unstandardized Standardized 

Independent coefficient coefficient 

variable (b) (ß) t-ratio p

Square root of 

hummock area 0.024 0.682 2.15 0.03

Hummock 

substrate type -0.678 -0.178 -1.08 0.29

Square root 

area x substrate 

type -0.006 -0.188 -0.63 0.53

Constant 1.1663 0 1.29 0.20

a

 Results of standard multiple regression performed between Atlantic white-cedar 

seedling number per hummock as the dependent variable and hummock substrate 

type, area, and their interaction as the independent variables at Brown Mill Pond, 

Rye, New Hampshire (July 2000). Hummock area and seedling number were 

square root transformed prior to analysis.
35

in relation to soil type. Although germination studies alone 

may not determine long-term establishment requirements, 

greenhouse experiments indicate stronger germination on 

peat moss than sand (Mylecraine and Zimmermann 2000). 

The factor explaining this difference in germination is still 

unknown (Mylecraine and Zimmermann 2000). Even though 

cedar seedlings appear to grow best in peat substrate, 

sphagnum moss, moist mineral soil, and rotten wood have 

also been reported as suitable cedar seedbeds (Mylecraine 

and Zimmermann 2000).

There are three possible explanations for a lack of cedar 

establishment on tussock hummocks relative to moss-litter

hummocks. First, tussock hummocks may differ from mosslitter hummocks in elevation relative to the water table. 

However, elevations of tussock hummocks were statistically 

similar to elevations on moss-litter hummocks where seedlings were established.

Second, the unsuitability of tussock substrate for germination and growth was discounted during specific experimental 

tests in the field (Gengarelly 2003).

The third possible explanation is the most plausible: the lack 

of cedar on tussocks may be due to the relatively small size 

of tussock hummocks, which on average were 32 percent as 

Figure 2—Results of Atlantic white-cedar seedling survey conducted in the pond edge community at Brown Mill Pond, 

Rye, NH. (A) The number of plots with cedar seedlings for each elevation class on moss-litter hummocks. Elevations were 

adjusted to a single water table height in July (July 3, 2000). (B) Percent of plots at each elevation with cedar seedlings. 

Number above elevations gives sample size of that class. Number of plots with seedlings at each elevation

25

20

15

10

5

0

0–5 5.1–10 10.1–

15

15.1–

20

20.1–

25

25.1–

30

30.1–

35

35.1–

40

40.1–

45

45.1–

50

50.1–

55

55.1–

60

Plots at each elevation with seedlings (percent)

120

100

80

60

40

20

0

0–5 5.1–10 10.1–

15

15.1–

20

20.1–

25

25.1–

30

30.1–

35

35.1–

40

40.1–

45

45.1–

50

50.1–

55

55.1–

60

4

15

24

17

14

14

15 8 1 1 1

Elevation relative to the water table (cm)
36

large as moss-litter hummocks. Wind-dispersed cedar seed 

is more likely to encounter a larger hummock than a small 

one. The multiple regression analysis including hummock 

substrate type and hummock area offered support for this 

hypothesis, as substrate was not a significant predictor of 

seedling number per hummock when hummock area was 

included in the model (table 3). This analysis overall only 

explained 40 percent of the variance in seedling number per 

hummock, so hummock area may only partially explain the 

lack of seedlings on tussocks at Brown Mill Pond. Additional 

factors limiting cedar establishment on tussock hummocks 

remain unclear. The multivariate analysis suggested that 

neither density of competing herbs and shrubs nor percent 

canopy cover played a strong determining role in cedar seedling distribution.

Elevation Relative to the Water Table

At Brown Mill Pond, seedlings were less likely to occur at the 

lowest and highest elevations of the moss-litter hummocks. 

Most seedlings were found 10 to 25 cm above the water table.

Similar to the pattern at Brown Mill Pond, Ehrenfeld (1995b) 

suggested that cedar seedlings were absent from lowest 

microsites, especially the bottom 20 cm of hummocks relative

to the hollow surface, studied in New Jersey. In fact, a band 

of cedar seedlings at the intermediate zone was reported in

New Jersey by Ehrenfeld (1995b) (Personal communication.

2001. J.G. Ehrenfeld, Professor, 126 Environment and Natural

Resource Sciences Building, Cook Campus, 14 College Farm

Road, New Brunswick, NJ 08901-8551) in sites where hummock height was large enough to include an intermediate 

elevation (∼ 35 to 55 cm above the hollow surface). Similarly, 

Akerman (1923) indicated cedar survival was best at the 

mid-section of rotting stumps.

Ehrenfeld (1995a, 1995b) suggested that microtopography 

may affect cedar seedling distribution on hummocks through 

its effects on water availability. The lack of seedlings in the 

hollows is attributed to frequent flooding in these depressions 

(Allison and Ehrenfeld 1999, Mylecraine and Zimmermann 

2000). In general, wetland woody species establish on 

elevated microsites, avoiding standing water (Huenneke and 

Sharitz 1990, Titus 1990). Conversely, the highest elevations of hummocks at Brown Mill Pond may be too dry for 

establishment of cedar, which requires sufficient moisture for 

survival (Allison and Ehrenfeld 1999, Little 1950). 

Other Factors

Previous research offers conflicting evidence regarding competing vegetation and light requirements (Buell and Cain 1943,

Hickman and Neuhauser 1977, Korstian and Brush 1931, 

Little 1950, Motzkin 1990, Mylecraine and Zimmermann 

2000). According to Buell and Cain (1943) open seedbeds 

free of competing vegetation in North Carolina were optimal 

for cedar establishment. However, Korstian and Brush (1931) 

found that seedlings become established under the shade 

of shrubs. The present survey was conducted in a habitat 

where light probably is not limited. 

Herbivory may also limit seedling presence and absence in

certain parts of cedar’s geographic range. In New Jersey deer

browse has contributed to great losses of cedar seedling 

presence in many wetlands (Kuser and Zimmermann 1995, 

Zimmermann 1997). Although herbivory was not measured 

at this site herbivory appeared to be rare or uncommon at 

Brown Mill Pond during the course of this study.

Distance to the nearest probable parent tree was not as 

strong a factor as elevation and substrate in determining 

cedar seedling presence. Perhaps the proximity of seed 

source was not as important as other factors because the 

pond edge canopy was dominated by both Atlantic whitecedar and red maple (Gengarelly 1999). However, in a study 

that compared six wetlands, Allison and Ehrenfeld (1999) 

suggest that cedar establishment was associated with a 

cedar canopy that served as a dependable cedar seed 

source.

In general, disturbance (e.g., windthrow, commercial harvesting, fire, drought, or flooding) is expected to alter the available

habitats in a wetland. For instance, extensive drought during 

the growing season may permit seedling establishment in 

the lowest elevations, typically areas devoid of seedlings due 

to standing water (Allison and Ehrenfeld 1999). Ehrenfeld 

(1995b) showed that sites with a history of more frequent 

windthrow had taller hummocks and the distribution of tree 

seedlings, including cedar, shifted to slightly higher elevations in these wetlands. Thus, if Brown Mill Pond experiences 

a disturbance in the near future, then the current seedling 

distribution patterns are likely to change.

CONCLUSION

This study describes the microsite conditions associated with

the cedar seedling distribution at Brown Mill Pond. Specifically, cedar seedlings occurred in scattered clumps on mosslitter hummocks typically 10 to 25 cm above the water table. 

Seedlings were absent from tussock sedge hummocks; however, tussock sedge hummocks were smaller than moss-litter 

hummocks. These patterns suggested that seedling distribution may be controlled by moisture as a function of elevation 

and edaphic conditions associated with different substrates. 

However, these relationships are statistical associations 

and only manipulative field experiments that rigorously test 

the exact microhabitat conditions will determine the causal 

factors in cedar establishment.

ACKNOWLEDGMENTS

We gratefully acknowledge Mr. and Mrs. Carroll Brown for 

their encouragement and funding, The Nature Conservancy 

who allowed us to conduct research at Brown Mill Pond, 

Drs. R.T. Eckert, L.A. Lord, C.D. Neefus, F.T. Short, and A.W. 

Stork for their support and advice, as well as the reviewers 

for their helpful comments on earlier drafts.

LITERATURE CITED 

Akerman, A. 1923. The white cedar of the Dismal Swamp. Virginia 

Forestry Publication 30: 1-21.

Allison, S.K.; Ehrenfeld, J.G. 1999. The influence of microhabitat 

variation on seedling recruitment of Chamaecyparis thyoides and

Acer rubrum. Wetlands 19(2): 383-393.

Buell, M.F.; Cain, R.L. 1943. The successional role of Southern white 

cedar, Chamaecyparis thyoides, in southeastern North Carolina. 

Ecology 24(l): 85-93.
37

Ehrenfeld, J.G. 1995a. Microtopography and vegetation in Atlantic 

white-cedar swamps: the effect of natural disturbances. Canadian 

Journal of Botany. 73: 474-484.

Ehrenfeld, J.G. 1995b. Microsite differences in surface substrate 

characteristics in Chamaecyparis swamps of the New Jersey 

Pinelands. Wetlands 15(2): 183-189.

Frazer, G.W.; Canham, C.D.; Lertzman, K.P. 1999. Gap Light 

Analyzer: imaging software to extract canopy structure and gap 

light transmission indices from true-color fisheye photographs, 

users manual and program documentation. Milbrook, NY: Simon 

Fraser University, Burnaby, British Columbia, and the Institute of 

Ecosystems Studies.

Gengarelly, L. 1999. Structure and dynamics of Atlantic white-cedar 

stands, Brown Mill Pond, Rye, New Hampshire. Durham, NH: 

University of New Hampshire. M.S. thesis.

Gengarelly, L. 2003. Factors associated with Atlantic white-cedar 

seedling recruitment on microtopographic and landscape scales, 

Brown Mill Pond, Rye, New Hampshire. Durham, NH: University of 

New Hampshire. Ph.D. thesis.

Haas, M.J.; Kuser, J.E. 1999. Effects of propagule type, geographic 

origin, and fertilization on first year performance of Atlantic whitecedar (Chamaecyparis thyoides) in New Jersey. Gen. Tech. Rep. 

SRS–27. In: Shear T.H.; Summerville, K.O., eds. Atlantic whitecedar: ecology and management symposium. Asheville, NC: U.S. 

Department of Agriculture, Forest Service, Southern Research 

Station: 22-26.

Hickman, J.C.; Neuhauser, J.A. 1977. Growth patterns and relative 

distribution of Chamaecyparis thyoides and Acer rubrum in 

Lebanon State Forest, New Jersey. Bartonia 45: 30-36.

Huenneke, L.F.; Sharitz, R.R. 1990. Substrate heterogeneity and 

regeneration of a swamp tree Nyssa aquatica. American Journal 

of Botany. 77: 413-419.

Kelsea, R.J.; Gove, J.P. 1994. Soil survey of Rockingham County, 

New Hampshire. United States Department of Agriculture.

Korstian, C.F.; Brush, W.D. 1931. Southern white cedar. Tech. Bull. 

251. Washington, D.C.: U.S. Department of Agriculture.

Kuser, J.E.; Zimmermann, G.L. 1995. Restoring Atlantic white-cedar 

swamps: techniques for propagation and establishment. Tree 

Planters’ Notes 46(3): 78-85.

Laderman, A.D. 1989. The ecology of the Atlantic white cedar 

wetlands: a community profile. U.S. Fish Wildlife Service. Biolog. 

Rep. 85 (7.21).

Laderman, A.D.; Golet, F.; Sorrie, B.; Woosley, H. 1987. Atlantic white 

cedar in the glaciated Northeast. In: Laderman, A.D., ed. Atlantic 

White Cedar Wetlands. Boulder, CO: Westview Press: 19-34.

Little, S. 1950. Ecology and silviculture of white cedar and 

associated hardwoods in southern New Jersey. Yale University 

School of Forestry Bulletin 56: 1-103.

Lord, L.; Lee, T.D. 2001. Interactions of local and regional processes: 

species richness in tussock sedge communities. Ecology 82(2): 

313-318.

Motzkin, G. 1990. Age structure and successional status of the 

Marconi Atlantic Cedar Swamp, Cape Cod National Seashore, 

So. Wellfleet Massachusetts. Amherst, MA: University of 

Massachusetts. M.S. thesis.

Mylecraine, K.A.; Zimmermann, G.L. 2000. Atlantic white-cedar 

ecology and best management practices manual. Trenton, NJ: 

New Jersey Forest Service.

Norusis, M.J. 1999. SPSS 9.0 guide to data analysis. Upper Saddle 

River, NJ: Prentice-Hall Publisher.

Sperduto, D.D.; Ritter, N. 1994. Atlantic white cedar wetlands of 

New Hampshire. Boston, MA: Environmental Protection Agency 

Wetlands Protection Section-Region 1.

Stoltzfus, D.L.; Good, R.E. 1998. Plant community structure in 

Chamaecyparis thyoides swamps in the New Jersey Pinelands 

Biosphere Reserve, USA. In: Laderman, A.D., ed. Coastally 

restricted forests. NY: Oxford University Press: 142-155.

Titus, J.H. 1990. Microtopography and woody plant regeneration 

in hardwood floodplain swamp in Florida. Bulletin of the Torrey 

Botanical Club. 117: 429-437.

Wilkinson, L.; Hill, M.; Welna, J.P.; Birkenbeuel, G.K. 1992. SYSTAT 

Statistics. Version 5 edition. Evanston, Illinois: SYSTAT.

Zimmermann, G. 1997. The Atlantic white-cedar regeneration 

experiments: Final Report. Submitted to the NJDEP and U.S. 

Department of Agriculture Forest Service. Pomona, NJ: Richard 

Stockton College of New Jersey.
38

INTRODUCTION

Significant decline of Atlantic white-cedar [Chamaecyparis 

thyoides (L.) B.S.P.; AWC] over the past two centuries (Frost

1987, Harshberger 1916, Kuser and Zimmermann 1995, Little

1950, Mylecraine and Zimmermann 2003) has led to much 

recent interest in its management and restoration in New 

Jersey (Haas and Kuser 1999, Mylecraine and Zimmermann 

2003, Mylecraine and others 2003b) and throughout the species range (Bryant 1999, Eagle 1999, Hinesley and Wicker 

1999, Laderman 1989). Several important factors need to 

be considered, including optimal site conditions to promote 

cedar regeneration, appropriate restoration techniques, and 

the type and source of propagules used. The geographic 

source material for introduction should be a major consideration (Handel and others 1994), as the ultimate success of a 

project may depend on choosing genetically adapted material (Lesica and Allendorf 1999). 

Patterns of genetic variation and the degree of localized adaptation vary among species, and must be determined by analyzing both genetic and phenotypic data. Genetic markers, 

such as allozymes, microsatellites, and AFLPs (amplified 

fragment length polymorphisms) may be used to determine 

the amount of population and regional differentiation in a 

species, and we have used allozyme data to establish that 

significant regional variation is present within white-cedar 

(Mylecraine and others 2003a). It is well known, however, 

that neutral genetic markers may underestimate the degree 

of variation in morphological, growth and/or reproductive 

traits, as these latter traits will likely be more influenced by 

natural selection pressures (Lewontin 1984, Pfrender and 

others 2000, Wheeler and Guries 1982). Analysis of phenotypic variation and field performance of different provenances 

in different localities would be more relevant for determining 

potential restoration success. 

Provenance variation is evident in AWC, although relatively 

few populations have been examined to date, and the extent 

and pattern of the differences remain unclear. Haas and 

Kuser (1999) found first year growth of the high elevation 

(457 m) stand at High Point, NJ, to be significantly lower than 

that of other source populations in the State, when grown 

in a common garden experiment in central New Jersey. A 

North Carolina population grew about the same as two of 

the New Jersey populations in the first year (Haas and Kuser 

1999), but exceeded the New Jersey populations in height in 

subsequent years (Dugan and Kuser 2003). Jull and others 

(1999) examined growth rates of seedlings from six AWC

provenances under controlled conditions and found differences in temperature optima among provenances. In another 

study, stratification requirements for seed germination varied 

among provenances (Jull and Blazich 2000). Summerville 

and others (1999) examined variation among several North 

Carolina populations from three different soil types and 

found that seedlings from parent trees occupying wet mineral 

soils were frequently the best performers on mineral sites. 

Conversely, seedlings from parent trees occupying organic 

soils were frequently among the best performers on organic 

sites, indicating some association between environmental 

and genetic factors within the species. Prior to the current 

study, no rangewide provenance trials had been established 

for AWC. 

To examine geographic patterns of adaptive variation in 

AWC, we have established three rangewide provenance 

plantations, two in New Jersey and one in North Carolina. 

GEOGRAPHIC VARIATION IN ATLANTIC WHITE-CEDAR:

PRELIMINARY PROVENANCE RESULTS

Kristin A. Mylecraine, John E. Kuser,

George L. Zimmermann, and Peter E. Smouse1

1 Kristin A. Mylecraine, Postdoctoral Researcher, Ohio State University, Department of Evolution, Ecology and Organismal Biology, Columbus, 

OH 43210; John E. Kuser, Professor Emeritus, Rutgers, the State University of New Jersey, Department of Ecology, Evolution and Natural 

Resources, New Brunswick, NJ 08901; George L. Zimmermann, Professor, The Richard Stockton College of New Jersey, Division of Natural 

Sciences and Mathematics, Pomona, NJ 08240; Peter E. Smouse, Professor, Rutgers, the State University of New Jersey, Department of 

Ecology, Evolution and Natural Resources, New Brunswick, NJ 08901.

Citation for proceedings: Burke, Marianne, K.; Sheridan, Philip, eds. 2005. Atlantic white cedar: ecology, restoration, and management: 

Proceedings of the Arlington Echo symposium. Gen. Tech. Rep. SRS-91. Asheville, NC: U.S. Department of Agriculture, Forest Service, 

Southern Research Station. 74 p.

Abstract—We present first year results from rangewide provenance plantations of Atlantic white-cedar [Chamaecyparis 

thyoides (L.) B.S.P.], established at (1) Richard Stockton College of New Jersey, (2) Brendan T. Byrne State Forest, New Jersey,

and (3) Hofmann Forest, North Carolina. Each plantation includes rooted cuttings from thirty different source populations. During

the first year, we observed reduced winter survival among extreme southern provenances (Georgia, Florida, and Mississippi 

populations) planted at Richard Stockton college. We also observed significant differences in height growth among planting 

sites and provenances, with stecklings planted at Hofmann Forest growing significantly more than those at the two New 

Jersey locations. Provenances originating from mid-latitudes performed best at all three planting locations. These results 

should be taken into account when choosing stock materials for regeneration and restoration throughout the species range.

Keywords: Adaptive variation, Chamaecyparis thyoides, Cupressaceae, growth, phenotypic variation.
39

Our specific objectives are (1) to quantify the extent and 

pattern of provenance variation within AWC, and (2) to identify appropriate source populations for restoration in North 

Carolina and New Jersey.

METHODS

Populations

Between August 1999 and January 2001, we collected 

foliage material from approximately 20 individuals from each 

of 34 populations, throughout the entire range of Atlantic 

white-cedar. The locations of these populations are listed in 

table 1. 

Propagation

From each individual, we made approximately 10 cm foliage 

cuttings, stripped the bark from the lower 2 cm, along one 

side of the branch, and dipped the branches in rooting 

hormone (Hormodin number 3, Geiger companies). We 

rooted these cuttings in pine cells (1.0 inch diameter by 6.3 

inches long; Stuewe & Sons, Inc.) in a mistbed at the New 

Jersey Agricultural Experiment Station research greenhouse 

(Rutgers University), where they received mist for 6 seconds 

every 6 minutes until roots developed. After cuttings were 

successfully rooted, we applied a 20–20–20 fertilizer formulation about once a month. The cuttings grew fast enough 

so that we subsequently had to transplant many of them 

into larger pots (D40 Deepot Cells, 2.5 inch diameter by 10 

inches long; Stuewe & Sons, Inc.), before outplanting.

Plantations

We have established three provenance plantations to date 

(fig. 1). We planted the first, located at the Natural Sciences 

and Mathematics (NAMS) arboretum at the Richard Stockton 

College of New Jersey (39°29 N, 74°33 W), during fall 2001. 

This planting is located on an upland site, with sandy soil, 

and is irrigated during the growing season. To deter whitetailed deer browsing, the site is surrounded by an electric 

fence, and individual cuttings are protected with individual 

tree shelters (12 inches wide by 36 inches tall; Terra Tech). 

Table 1—AWC populations included in rangewide provenance plantations at Richard Stockton College of New Jersey 

(SC), Brendan T. Byrne State Forest, NJ (BB) and Hofmann Forest, NC (HF)

Abbr. Population Lat. Long. SC BB HF

ME-AB Appleton Bog TNC Preserve, ME 44o20’N 69o16’W X X X

ME-SH Saco Heath TNC Preserve, ME 43o33’N 70o28’W X X X

NH-RYE Rye Cedar Stand, NH 42o59’N 70o47’W X X X

MA-WH Woods Hole, MA 41o32’N 70o39’W X X X

CT-PF Pachaug State Forest, CT 41o35’N 71o53’W X X X

NY-CB Cranberry Bog Preserve, NY 40o54’N 72o41’W X X X

NY-SF Sterling Forest, NY 41o11’N 74o17’W X X X

NJ-BB Brendan T. Byrne State Forest, NJ 39o53’N 74o30’W X X X

NJ-BR Bass River State Forest, NJ 39o38’N 74o26’W X X X

NJ-BP Belleplain State Forest, NJ 39o11’N 74o51’W X X X

DE-MN Middleford North TNC Preserve, DE 38o40’N 75o33’W X X X

MD-AE Arlington Echo, MD 39o04’N 76o37’W X X X

MD-CC Cypress Creek, MD 39o04’N 76o32’W X X

MD-SC Sullivan’s Cove, MD 39o04’N 76o33’W X X

VA-IP Franklin, VA 36o35’N 76o54’W X

NC-DS Great Dismal Swamp NWR, NC 36o32’N 76o28’W X X X

NC-D Alligator River NWR, NC 35o48’N 75o54’W X X X

NC-BC Bladen, Cumberland Counties, NC 34o50’N 78o44’W X X X

NC-ML Moore, Lee Counties, NC 35o19’N 79o11’W X X X

NC-BR Brunswick County, NC 34o05’N 78o20’W X X X

SC-W Waccamaw River, SC 33o54’N 78o43’W X X

SC-SH Sand Hills State Forest, SC 34o33’N 80o04’W X X

SC-SP Shealy’s Pond Heritage Preserve, SC 33o52’N 81o14’W X X X

SC-C Cheraw State Park, SC 34o38’N 79o54’W X

SC-G The Bishop Gravatt Center, SC 33o44’N 81o35’W X X

SC-P Poinsett Electr. Bombing Range, SC 33o47’N 80o28’W X X

GA-WC Whitewater Creek, GA 32o28’N 84o16’W X X X

GA-JC Juniper Creek, GA 32o31’N 84o32’W X

FL-ONF Ocala National Forest, FL 29o12’N 81o39’W X X X

FL-ANF Apalachicola National Forest, FL 30o08’N 84o53’W X X X

FL-TH Tates Hell State Forest, FL 29o51’N 84o51’W X X X

FL-YR Yellow River, FL 30o34’N 86o57’W X X X

FL-BW Blackwater River State Forest, FL 30o51’N 86o51’W X X X

MS-BC Bluff Creek, MS 30o32’N 88o41’W X X X
40

We planted the second plantation within Hofmann Forest, 

North Carolina (34°52 N, 77°18 W), during spring 2002. This 

is a lowland site, with organic soil, and is surrounded by 

loblolly pine plantations. Prior to planting, all existing vegetation was removed. Although there is little evidence of deer 

damage in the area, we have again protected the plantings 

with individual tree shelters. We established the third plantation at Brendan T. Byrne State Forest, New Jersey (39°56 N, 

74°28 W), in spring 2002. This plantation is embedded within 

a 20 ha Atlantic white-cedar mitigation project (Mylecraine 

and others 2003b) and occupies an organic sandy soil. 

Experimental Design

For each of the three planting locations, we selected a 

total of 30 provenances to include in the design (table 1). 

Twenty-five provenances were included at all three planting 

locations, but the remaining five provenances varied across 

sites due to the availability of sufficient rooted material. 

Each site was divided into three replicates, within each of 

which we established six blocks. Within a single replicate, 

we planted cuttings into a randomized block design, with 

each block containing one steckling from each of 30 populations, randomized (as single-tree plots) within the block. We 

planted ramets from six different genets from each provenance, a different genet for each of the six blocks. Thus, we 

had 180 genotypes (6 from each of 30 provenances) planted 

within a replicate, each genotype replicated once. The entire 

design was then replicated three times per site. Overall, each 

of 6 genets is represented 3 times at each site, for a total of 

18 stecklings from each provenance. We planted stecklings 

at 1.8 m by 1.8 m spacing, with 2.4 m between blocks. The 

physical layouts of the planting designs varied slightly among 

the three locations due to site-specific spatial configurations.

Survival and Growth Measurements

For the Richard Stockton college plantation, planted during 

fall 2001, we were able to assess first winter survival. The 

other two plantations were planted in spring, so we were 

not yet able to assess winter hardiness. For all three plantations, we monitored first season survival and growth. We 

measured cutting height at the time of planting and again at 

the end of the first growing season (2002), to calculate first 

season height growth. We performed four separate analyses 

of variance (ANOVA) using SAS (SAS Institute) to test for 

differences in growth among planting sites and provenances. 

If the data did not meet the normality assumption for ANOVA, 

we used a log transformation. First, we performed a twofactor, combined site analysis to test the following effects: 

site, provenance, and site*provenance. For this analysis, we 

included only the 25 provenances that were planted at all 

three sites. We treated site as a fixed effect and provenance 

as a random effect, and conducted the analysis using PROC 

MIXED. To further investigate site differences, we performed 

two orthogonal contrasts, comparing (1) Hofmann Forest 

vs. the two New Jersey plantations, and (2) Brendan T. 

Byrne State Forest vs. Richard Stockton college. Second, 

we conducted three individual site one-factor ANOVAs to 

assess provenance differences within each site. To examine 

the relationship between mean height growth and the latitude 

of provenance origin, we performed regression analyses for 

each planting location.

RESULTS

Survival

Over the first winter (2001–2002), we observed variation in 

survival rates between provenances at the Richard Stockton 

college plantation (fig. 2). Survival among northern and central provenances (Maine to Maryland) was high, ranging from

Figure 1—Range of AWC, redrawn and modified from Little 

(1971), showing the locations of three provenance plantations,

at Richard Stockton College of New Jersey (SC), Brendan T. 

Byrne State Forest, NJ (BB), and Hofmann Forest, NC (HF).

Figure 2—Percentage of cuttings surviving through the first 

winter (2001–2002) at Richard Stockton College of New 

Jersey, for 30 AWC provenances, plotted by latitude of 

source population.
41

94 to 100 percent. There was considerable variation in survival rates among North Carolina and South Carolina provenances, ranging from 66.7 to 100 percent. Among southern 

provenances (western Georgia, peninsular Florida and Gulf 

Coast populations), survival was reduced, ranging from 44 

to 83 percent. These data suggest a non-linear relationship

between latitude and first season survival (fig. 2). We did not

observe any additional mortality through the first growing 

season. The remaining two plantations (Brendan T. Byrne 

State Forest and Hofmann Forest) were planted in the spring,

so we were not able to assess winter survival. However, 

survival rates through the first growing season were high for

all provenances (ranging from 89 to100 percent) at both sites.

First Season Height Growth

Results of the combined site ANOVA indicate significant 

planting site, provenance, and site*provenance effects (table 

2). All populations grew substantially more at the Hofmann 

Forest, North Carolina site than at the two New Jersey sites, 

as indicated by the highly significant NJ vs. NC contrast. 

The significant site*provenance (genotype by environment) 

interaction suggests that the relative performances of provenances varied across sites, and requires that we examine 

the provenance pattern at each site individually. At all three 

sites, we found highly significant (p < 0.0001) within-site 

differences among provenances. Figure 3 depicts mean provenance growth at each site, plotted by latitude of provenance 

origin. The overall growth pattern was similar across sites. 

Height growth was greatest for populations from the southern 

and mid-Atlantic Coastal Plain, with North Carolina populations among the best performers at all three sites. Florida 

and Gulf coast populations exhibited reduced height growth, 

particularly at the two New Jersey plantations. New England 

populations also exhibited reduced growth, compared to

those from the southern Atlantic Coastal Plain. We found 

significant polynomial relationships between growth and 

source latitude at both Brendan T. Byrne State Forest and

Hofmann Forest, and a similar, but non-significant (p = 0.072)

trend at Richard Stockton college (fig. 3). 

DISCUSSION

This study represents the first rangewide provenance test 

of Atlantic white-cedar. The newly established provenance 

plantings are obviously in their early stages of development, 

and must therefore be viewed as a “work in progress”; this 

project will continue for several years to come, because 

geographic variation in growth and survival patterns is influenced by inter-annual climatic variability and may take years 

to manifest itself in long-lived tree species. 

We did, however, find significant variation in both first season 

survival and growth among different white-cedar provenances.

Survival through the first winter at Richard Stockton College 

of New Jersey was much reduced for southern populations, 

indicating that either the site or the climatic factors were not 

optimal for these populations. Survival in subsequent years, 

at all three planting locations, will be important in making the 

distinction between these two possibilities. We also observed 

significant variation in height growth among planting sites 

and source populations. North Carolina populations were 

among the best performers at all three sites. The growth 

patterns agree with the earlier work by Haas and Kuser 

(1999) that North Carolina populations may outgrow native 

New Jersey populations in common gardens. However, the 

growth differences among provenances were only slight after 

the first year, and it may take several years for these patterns 

to fully develop. 

ACKNOWLEDGMENTS

We would like to thank numerous individuals and organizations for helping us to identify, locate, and collect foliage 

material from populations. We would also like to thank Bill 

Pickens, the North Carolina Forest Service, Robert Cox, 

Stephanie Turner, Lisa Bono, and Chris Dugan for their field 

assistance. This study was supported by U.S. Department of 

Agriculture/McIntire Stennis 17307 and 17309, and NSFBSR-0089238.

Table 2—Results of the combined site Analysis of Variance (ANOVA) and orthogonal 

contrasts, conducted on log-transformed steckling height growth at all three planting 

sites. Site is treated as a fixed effect, and provenance is treated as a random effect

Source df SS MS F P

Site 2 635.6 317.8 662.9 <0.0001

 NJ vs. NC 1 630.6 630.6 1309.6 <0.0001

 RS vs. BB 1 1.0 1.0 2.1 0.1545

Provenance 24 52.1 2.2 4.5 <0.0001

Site*Provenance 48 23.1 0.5 1.5 0.0179

Error 1189 384.4 0.3 — —
42

LITERATURE CITED

Bryant, M.R. 1999. Linking ecosystem management, refuge 

management and Atlantic white-cedar restoration. In: Shear, 

T.H.; Summerville, K.O., eds, Atlantic white-cedar: Ecology and 

management symposium. Newport News, VA: Gen. Tech. Rep. 

SRS–27. Asheville, NC: U.S. Department of Agriculture, Forest 

Service, Southern Research Station: 8-9.

Dugan, C.P.; Kuser, J.E. 2003. Provenance variation in Atlantic whitecedar (Chamaecyparis thyoides) planted at Jackson, New Jersey. 

Bulletin of the New Jersey Academy of Science. 48: 7-11.

Eagle, T.R., Jr. 1999. Atlantic white-cedar ecosystem restoration 

on Alligator River National Wildlife Refuge and United States Air 

Force Dare County Range. In: Shear, T.H.; Summerville, K.O., 

eds. Atlantic white-cedar: Ecology and management symposium. 

Newport News, VA: Gen. Tech. Rep. SRS–27. Asheville, NC: U.S. 

Department of Agriculture, Forest Service, Southern Research 

Station: 13-17.

Frost, C.C. 1987. Historical overview of Atlantic white-cedar in the 

Carolinas. In: Laderman, A.D., ed. Atlantic white-cedar Wetlands. 

Boulder, CO: Westview Press: 257-264.

Haas, M.J.; Kuser, J.E. 1999. Effects of propagule type, geographic 

origin, and fertilization on first year performance of Atlantic 

white-cedar (Chamaecyparis thyoides) in New Jersey. In: Shear, 

T.H.; Summerville, K.O., eds. Atlantic white-cedar: Ecology and 

management symposium. Newport News, VA: Gen. Tech. Rep. 

SRS–27. Asheville, NC: U.S. Department of Agriculture, Forest 

Service, Southern Research Station: 22-26.

Handel, S.N.; Robinson, G.R.; Beattie, A.J. 1994. Biodiversity 

resources for restoration ecology. Restoration Ecology. 2: 230-241.

Harshberger, J.W. 1916. The vegetation of the New Jersey PineBarrens. Philadelphia, PA: Christopher Sower Company. 

Figure 3—Mean first season height growth for 30 AWC provenances planted at 

(a) Brendan T. Byrne State Forest, NJ, (b) Richard Stockton College of New Jersey, 

and (c) Hofmann Forest, NC (HF), plotted by latitude of origin.

y = -0.07x2 + 4.82x - 75.02

r

2

 = 0.23

p = 0.03

y = -0.07x2 + 5.60x - 87.42

r

2

 = 0.18

p = 0.07

y = -0.12x2 + 7.79x - 83.06

r

2

 = 0.29

p = 0.01
43

Hinesley, E.; Wicker, M. 1999. Atlantic white-cedar wetland restoration project at Pocosin Lakes National Wildlife Refuge. In: Shear, 

T.H.; Summerville, K.O., eds. Atlantic white-cedar: Ecology and 

management symposium. Newport News, VA: Gen. Tech. Rep. 

SRS–27. Asheville, NC: U.S. Department of Agriculture, Forest 

Service, Southern Research Station: 27-32.

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temperature, and light. HortScience. 35: 132-135.

Jull, L.G.; Ranney, T.G.; Blazich, F.A. 1999. Heat tolerance of 

selected provenances of Atlantic white-cedar. Journal of the 

American Society for Horticultural Science. 124: 492-497.

Kuser, J.E.; Zimmermann, G.L. 1995. Restoring Atlantic white-cedar 

swamps: Techniques for propagation and establishment. Tree 

Planters’ Notes. 46: 78-85.

Laderman, A.S. 1989. The ecology of Atlantic white-cedar wetlands: 

a community profile. Biolog. Rep. 85 (7.21). Washington, DC: U.S. 

Fish and Wildlife Service. 114 p.

Lesica, P.; Allendorf, F.W. 1999. Ecological genetics and the restoration of plant communities: mix or match? Restoration Ecology. 7: 

42-50.

Lewontin, R.C. 1984. Detecting population differences in quantitative 

characters as opposed to gene frequencies. The American 

Naturalist. 123: 115-124.

Little, E.L. 1971. Atlas of United States Trees: Vol. 1. Conifers and 

Important Hardwoods. Misc. Pub. 1146. Washington, DC: U.S. 

Department of Agriculture, Forest Service.

Little, S. 1950. Ecology and silviculture of white cedar and associated hardwoods in southern New Jersey. Yale University School of 

Forestry Bulletin. 56: 1-103.

Mylecraine, K.A.; Zimmermann, G.L. 2003. Atlantic white-cedar: 

Ecology and best management practices manual, 2d

 edition. 

Trenton, NJ: New Jersey Department of Environmental Protection, 

New Jersey Forest Service.

Mylecraine, K.A.; Kuser, J.E.; Zimmermann, G.L. [and others]. 2003a. 

Allozyme variation within and among selected populations of 

Atlantic white-cedar. In: Atkinson, R.B.; Belcher, R.T.; Brown, D.A., 

eds. Proceedings of the Atlantic white-cedar management and 

restoration ecology symposium. Newport News, VA: Christopher 

Newport University: 271-288.

Mylecraine, K.A.; Williams, R.R.; Zimmermann, G.L.; Kuser, J.E. 

2003b. Restoring Atlantic white-cedar on an abandoned blueberry 

field and cranberry bog in Lebanon State Forest, New Jersey. 

In: Atkinson, R.B.; Belcher, R.T.; Brown, D.A., ed. Proceedings 

of the Atlantic white-cedar management and restoration ecology 

symposium. Newport News, VA: Christopher Newport University: 

213-226. 

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concordance between genetic diversity estimates at the molecular 

and quantitative-trait levels. Conservation Genetics. 1: 263-269.

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1999. Ecotypic variation in Atlantic white-cedar in eastern North 

Carolina. In: Haywood, J.D., ed. Proceedings of the tenth biennial 

southern silvicultural research conference. Shreveport, LA: Gen. 

Tech. Rep. SRS–30. Asheville, NC: U.S. Department of Agriculture, 

Forest Service, Southern Research Station: 185-189.

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diversity, and morphological variation in Pinus contorta Dougl. 

Canadian Journal of Forest Research. 12: 595-606.
44

INTRODUCTION

The native range of Atlantic white cedar [Chamaecyparis 

thyoides (L.) B.S.P.] extends from Maine down the Atlantic 

coast to Florida and west along the Gulf of Mexico coast to 

Mississippi (Little 1950, Laderman 1987, 1989). The majority 

of cedar stands are found along the Atlantic coast, with fewer

stands along the Gulf of Mexico coast, and a very few disjunct

individuals or stands in Illinois, Indiana, and Ohio (Coulter, 

n.d., Patterson 1876, Schaffner 1932, Mohr 1901). The origin 

of these disjunct stands is unknown, as is whether they are 

natural populations or were planted by early settlers. Also 

unknown is whether cedars are regenerating at those sites. 

Korstian and Brush (1931) observed large stands of cedar in 

Alabama, Florida, Georgia, and Mississippi, but these stands 

were not quantitatively described and subsequent logging 

may have degraded or eliminated some of the stands. More 

recently, one stand in Mississippi (Eleuterius and Jones 1972)

along Bluff Creek near Vancleave, Jackson County and nine

stands in Florida (Ward and Clewell 1989) have been quantitatively studied and published in the literature. No stands in 

Alabama have been so studied. Ward and Clewell (1989) 

presented the most comprehensive description of known cedar

locations along the Gulf of Mexico coast, but the majority of 

stands they discussed included only a general location and 

little community composition data. In addition to the stand 

along Bluff Creek, Ward and Clewell (1989, page 11) report 

that in Mississippi cedar occurs along “...tributaries of the 

Escatawpa River and Pascagoula River, Jackson County; 

and branches of the Catahoula River, Pearl River County.” 

Ward and Clewell (1989, pages 10-11) further list cedar as 

occurring in “...headwater extensions of the Escambia River 

and Perdido River into Escambia County, Alabama; and 

tributaries entering the Perdido River, Perdido Bay, and Bon 

Secour Bay, Baldwin County, Alabama.” This sparse occurrence of gulf coast cedar may reflect how few large stands 

remain. Since little is known about cedar along its southern 

range, documenting the extent, health, and environmental 

condition of these populations is important.

Habitat degradation and conversion to other uses, such as 

agriculture, are serious problems across the entire range of

cedar (Little 1950). Many stands identified during the early part

of the 20th century were cut for lumber production (Korstian 

and Brush 1931). In Mississippi, some stands have been 

degraded by urbanization, erosion and/or land use changes 

(Personal communication. 2000. Mr. Joseph Cruthirds, 

Professor, Delgado Community College, 615 City Park Ave., 

New Orleans, LA 70119). Also, degradation of cedar swamps 

can result from manipulations of the surrounding habitat, 

which is known to have significant effects on nutrient cycling 

(Zhu and Ehrenfeld 1999) and plant community composition 

(Ehrenfeld and Schneider 1991) in these stands.

Information about management of cedar stands in the Southeastern United States is lacking. Although some information

on regeneration of cedar is available for the Atlantic coast

(Boyle and Kuser 1994, Carter 1987, Kuser and Zimmermann

1995, Little 1950), we cannot assume that gulf coast cedar 

swamps will function in a like manner because of differences 

in species composition, soils, climate, and a host of other 

factors. For example, Eleuterius and Jones (1972) found only 

20 percent of the plant species in a Mississippi cedar stand 

to be in common with Atlantic coast stands. Cedar stands in 

Florida had 20 percent of the plant species in common with 

Mississippi and 16 percent in common with Atlantic coast 

stands. This lack of similarity in species composition between 

regions indicates functional and physical differences that 

LOCATIONS OF ATLANTIC WHITE CEDAR IN

THE COASTAL ZONE OF MISSISSIPPI

John W. McCoy and Bobby D. Keeland1

1 John W. McCoy, General Biologist and Bobby D. Keeland, Ecologist, U.S. Geological Survey, National Wetlands Research Center, Lafayette, LA 

70506.

Citation for proceedings: Burke, Marianne, K.; Sheridan, Philip, eds. 2005. Atlantic white cedar: ecology, restoration, and management: 

Proceedings of the Arlington Echo symposium. Gen. Tech. Rep. SRS-91. Asheville, NC: U.S. Department of Agriculture, Forest Service, 

Southern Research Station. 74 p.

Abstract—Atlantic white cedar [Chamaecyparis thyoides (L.) B.S.P. cedar] is a tree species found in freshwater wetlands 

along a coastal band from Maine to Mississippi. Numerous studies have documented the occurrence of this species along 

the Atlantic seaboard, but relatively few studies have been conducted along the Gulf of Mexico coast. Nine stands in Florida 

have been quantitatively described in the literature, but only one stand in Mississippi and none in Alabama have been so 

described. Other cedar locations in Alabama and Mississippi have been mentioned, but these sites have not been inventoried. In Mississippi, cedar is considered imperiled, but it is currently unknown whether the existing populations are increasing 

or decreasing. The one stand described for Mississippi, located near Vancleave, in Jackson County, is degrading as a result 

of hydrologic regime modification and urbanization. Through contact with the Mississippi Natural Heritage Program, limited 

fieldwork and herbarium searches, we have identified an additional 22 sites where cedar occurs as at least individual trees. 

However, the size and species composition of these additional cedar stands is unknown. The discovery of these additional 

sites is encouraging and may suggest that the species is more common than previously thought. 

Keywords: Atlantic white cedar, Chamaecyparis thyoides, Gulf Coastal Plain, Mississippi, plant community composition. 
45

emphasize the need for more study of gulf coast cedar 

populations. 

The future health and sustainability of cedar populations in

the Southeastern United States are dependent upon achieving a greater understanding of the distribution, landscape 

position, abundance, and population dynamics of the existing 

stands. This is especially true for the western extent of its 

range. The objective of this manuscript is to take the first 

step and report on the known locations of cedar along the 

Mississippi Gulf Coast. 

METHODS

Locations of individual cedar trees or stands along the Gulf 

of Mexico Coast were determined from a variety of sources. 

The Mississippi Museum of Natural Science database provided the greatest number of locations in the form of field 

survey summaries (Personal communication. 2003. Ron 

Wieland, Botanist, Mississippi Museum of Natural Science, 

2148 Riverside Drive, Jackson, MS 39202). For each stand 

listed in the database the location, dominant and codominant

species and evidence of regeneration were listed. A few additional stands were located through contacts with numerous 

private individuals and Federal/State/NGO offices. Potential 

sites were visited and preliminary data gathered through 

casual observation. Lastly, some locations were identified 

through boat and land surveys conducted by the authors 

during 2002 and 2003.

RESULTS AND DISCUSSION

Historic Distribution

The natural distribution of cedar does not currently extend 

west of the Pearl River, even though environmental and soil 

conditions between the Pearl and Mississippi rivers appear 

to be appropriate for the successful growth and regeneration 

of the species (McCoy and others 1999, 2003). Apparently 

a population of cedar existed along Little Bayou Sara in 

West Feliciana Parish, LA, when warm temperate deciduous 

forest species dominated the area between 7,600 and 3,200 

years B.P. (Brown 1938, Givens and Givens 1987). This site 

is about 135 km west of the Pearl River. The cause of cedar 

extinction in this area is unknown. 

Current Stand Locations

A list of locations from the literature or unpublished data for 

Mississippi and Louisiana is included in table 1 and mapped 

on figures 1 and 2. A preliminary list of co-occurring tree and 

shrub species, family, and common names is presented in 

table 2 and cross referenced to locations given in table 1.

We found numerous sites with scattered cedar trees along 

the lower portions of both the Escatawpa and Pascagoula 

rivers in Jackson County, Mississippi. A small stand can be 

found along the lower Escatawpa River, on the north side of 

Interstate 10. The stand is located on Grand Bay National 

Wildlife Refuge and is between the Mississippi Welcome 

Center and the Escatawpa River bridge. Tree and shrub 

species associated with this cedar stand include sweetgum, 

live oak, baldcypress, red maple, Eastern red cedar, Chinese 

tallow tree, American witchhazel, yaupon, American holly,

blueberry, and Hercules’ club (see table 2 for scientific names).

Both sensitive and royal ferns were also observed at this site. 

A portion of the stand was damaged by a fire in 2001 and 

several cedar trees were killed. The most damage occurred 

on higher ground that grades into a longleaf pine stand. 

We found an additional stand along the bank of Bluff Creek, 

downstream of the Vancleave site, on the Mississippi Sandhill Crane National Wildlife Refuge, in Jackson County. Plant 

species associated with cedar were slash pine, black tupelo, 

water oak, sweetgum, red maple, Florida anise tree, swamp 

titi, large gallberry, deerberry, yaupon, clammy azalea, dwarf 

palmetto, summer grape, pitcherplant, and cinnamon fern. 

The stand consisted of about 50 cedar trees that ranged from

2 to 30 m in height. The largest cedar was 48.2 cm diameter

at breast height (d.b.h.). The northern end of this small stand

supported numerous seedlings and a few suppressed 

saplings. 

Another new cedar stand, located in the Black Creek Swamp,

near Hurley, Jackson County, Mississippi, is part of a wetland 

mitigation bank being developed by Wetlands Solutions, 

LLC under regulatory authority of the U.S. Army Corps of 

Engineers. Although cedar is a dominant canopy species 

in portions of this site, often with trees up to 35 m in height, 

the majority of the area is dominated by slash pine, canopysized black titi, swamp bay and sweet bay. Big-leaf gallberry 

was a common shrub in the area while sphagnum moss 

(Sphagnum sp.) and various ferns (royal, cinnamon and 

chain ferns) were important in the ground layer. Some visibly 

stressed and a few standing dead cedar were noted in 

the area. During our preliminary field trip in April 2002, we 

noted only two or three small clusters (< 100/m2

) of first-year 

cedar seedlings. Although no attempt was made to quantify 

shrub-sized cedars, few < 2 m tall were noted. This lack of 

regeneration is expected under a dense canopy (Korstian 

and Brush 1931, Laderman 1989). Sphagnum was present 

over an organic soil, but the leaf litter was primarily broadleaf.

We have not yet been able to verify the stands reported 

along branches of Catahoula Creek by Ward and Clewell 

(1989), but we have located a series of small stands 

scattered along Juniper Creek, a tributary of the East 

Hobolochitto Creek and the Pearl River in Pearl River 

County, just south of Poplarville, MS. These stands are just 

northwest of the headwaters of Catahoula Creek and may 

be the stands referred to by Ward and Clewell (1989). The 

limited portion of these stands that we have seen consists 

of bottomland hardwood forest with scattered cedar in low, 

wet areas, on slightly elevated areas within a braided stream 

area, or along the toe of the slope at the edge of the floodplain (see Messina and Conner 1998 for a description of 

toe-of-the-slope communities). Additional species include 

sweetbay, redbay, loblolly pine, black tupelo, baldcypress, 

swamp tupelo, and swamp titi. These stands are protected 

at the discretion of the forest manager for Weyerhaeuser, 

Inc. (Personal communication. 2003. Tina Knoll, Forester, 

Weyerhaeuser Inc., 211 Armstrong Road, Columbia, MS 

39429). However, even without activity within the cedar 

stands, silvicultural activity in the surrounding slash pine 

plantations may impact the cedar stands: degradation of 

cedar stands may occur as a result of fertilizer and other 

chemicals draining into the bogs, and a changed hydrology 

from drainage to enhance slash pine growth.
46

Table 1—Locations of Atlantic white cedar individuals and stands in Mississippi (including data on Louisiana plantations).

Many of these locations represent old collections with the current status of the tree or site unknown. Most of the data 

was obtained from the Mississippi Natural Heritage Program (MNHP) or observed during 2002. The general location of 

these sites is shown on figure 2. Data in the last column cross-references to species lists for each location, given in 

Table 2

Citation and/or

Site location Notes last observation noted Table 2

Forrest County, MS Camp Shelby training site; up to 29.6 ha in size; MNHP 1997,1998 L,M

seedlings present; gum-bay-pine site; extends into Observed 2002 

private land near Davis Creek a tributary of Black Creek.

George County, MS Not common; .5 km west of Howell, MS, west of MS/AL MNHP 1978 O

State line in Juniper bay.

Hancock County, MS Near Hwy 603 over the Jourdan River. MNHP 1967

Jackson County, MS 1

Beside Bluff Creek on natural levee. 2Largest cedar Observed 2002 B

stand in Mississippi; up to 60 feet above creek; stand 1MNHP 1968

1⁄2 mile wide. 3Quantitative description of the stand. 2Jones 1967 4

Cedars extend 11 km with a maximum width of 0.8 km. 3Eluterius and Jones 1972

4

Ward and Clewell 1989

Jackson County, MS A nice stand of cedar at Vancleave, MS, along a small Jones 1967 C

tributary of Bluff Creek. MNHP 2002

Jackson County, MS Moss Point Lumber Mill on Escatawpa River at pipeline MNHP 2002 D

crossing (Levee). Observed 2002

Jackson County, MS Moss Point Lumber Mill on Escatawpa at pipeline MNHP 2002 E

crossing (Marsh). Observed 2002

Jackson County, MS Escatawpa River 1.6 km above Moss Point Lumber Mill MNHP 2002 F

(Marsh). Observed 2002

Jackson County, MS Escatawpa River 1.6 km above Moss Point Lumber Mill MNHP 2002 G

(Levee). Observed 2002

Jackson County, MS Escatawpa River at Moss Point Lumber Mill (Levee MNHP 2002 H

along SW—most pipeline). Observed 2002

Jackson County, MS East bend on Bluff Creek just West of Paige Lake, MNHP 2002 I

Gautier Unit—MS Sandhill Crane NWR. Observed 2002

Jackson County, MS West bend of Bluff Creek .8 km west of Paige Lake, MNHP 2002 J

Gautier Unit—MS Sandill Crane NWR. Observed 2002

Jackson County, MS Hook on Bluff Creek at north boundary of Sec 34, MNHP 2002 K

Gautier Unit—MS Sandhill Crane NWR. Observed 2002

Jackson County, MS Welcome center nature trail at I-10. About 100 cedars MNHP 2002 M

with some dead from a recent fire. Few seedlings or Observed 2002

saplings. Narrow habitat between upland and swamp.

Jackson County, MS Growing along Brickyard Bayou 3.2 km south of George MNHP 1966

County line and Hwy 63.

Jackson County, MS Occasional in baldcypress/tupelo swamp 8-9 miles MNHP 1951

north of Escatawpa River along Jackson Creek. 

Jackson County, MS On Jackson Creek in sandy soil 4.1 km north of MNHP 1979

Interstate 10.

Jackson County, MS 12.8 km south of George/Jackson County line along MNHP 1966

Hwy 57.

Jackson County, MS East bank of Escatawpa River in mesic woods with MNHP 1978 

baldcypress 1.7 km from Mississippi/Alabama border.

Jackson County, MS In sandy soil along Escatawpa River 1.7 km NE of MNHP 1980 

Orange Grove 2.5 km south of Interstate 10. Observed 2002

(continued)
47

Another new stand was found along Davis Creek on the 

DeSoto National Forest, just west of the Camp Shelby Army 

National Guard training site in Forrest County. This site, just 

south of Hattiesburg, MS, is characterized by a past blowdown event of unknown timing that uprooted or snapped 

many cedar trees. Extensive regeneration in the form of 

cedar seedlings to saplings can be found throughout the 

canopy gap area caused by the storm. Blowdown events 

are important in the regeneration of cedar stands. In fact, 

Ward and Clewell (1989) noted that cedar seedlings tend to 

become established in cohorts when conditions are correct, 

such as after a major blowdown that removes at least part 

of the canopy. Cedar seedlings and saplings outside of the 

disturbed area on the Camp Shelby site were less common. 

Table 1—Locations of Atlantic white cedar individuals and stands in Mississippi (including data on Louisiana plantations).

Many of these locations represent old collections with the current status of the tree or site unknown. Most of the data 

was obtained from the Mississippi Natural Heritage Program (MNHP) or observed during 2002. The general location of 

these sites is shown on figure 2. Data in the last column cross-references to species lists for each location, given in 

Table 2 (continued)

Citation and/or

Site location Notes last observation noted Table 2

Jackson County, MS Shrubby 2-m tall in savannah on Saracenia Road MNHP 1977 

1.5 km north of Interstate 10.

Jackson County, MS Scattered young trees in mucky bayhead between MNHP 1983

Escatawpa River and Big Creek 3.4 km south of 

Hwy 614, 1.6 km west of Mississippi/Alabama border.

Jackson County, MS Up and down stream from Interstate 10 crossing of MNHP 1983 

Escatawpa River.

Jackson County, MS North end of Goodes Lake at Jackson Creek 2.6 km MNHP 1983 

north of Interstate 10.

Jackson County, MS Along sandy banks of Escatawpa River at Big Creek. MNHP 1983 

Observed 2002

Jackson County, MS Several 15-25 cm dbh trees 4.2 km east of Hurley, MS, MNHP 1985 

along Spring Creek.

Jackson County, MS Frequent near Black Creek 4.8 km north of Moss Point MNHP 1984 

along Interstate 10.

Jackson County, MS Moss point, along east bank of the East Pascagoula MNHP 1983 

River in pine woods.

Jackson County, MS South of Vancleave, Herbarium Collection. Li 1962 (Li 1962)

Jackson County, MS Black Creek Swamp near Hurley, MS, 7.5 km west of Observed 2002

the Escatawpa River. Many large and small cedar, 

a few dead or dying.

Juniper Creek, 1

Scattered patches along banks and in swampy area. 1MNHP 1973 A

Pearl River County, MS 2

Disturbed and logged area; is the western most 2Eluterius and Jones 1972

extension known at the time; 3Possible reference. 3Korstian 1931

3

Little 1950

Observed 2002

Pearl River County, MS A number of trees in swamp up to 7.6-m tall and 25-cm MNHP 1968 

diameter. Juniper Swamp along Moren Creek 9.6 km 

SE of Poplarville along Hwy 53.

Pearl River County, MS Trial plantings of cedar 1989, Pink Smith Road off McCoy and others 2003

Hwy 43.

West Feliciana Parish, Holocene fossils of cedar twigs. Givens and Givens 1987 

LA

West Feliciana Parish, Pleistocene fossils of cedar twigs. Brown 1938

LA

St. Tammany Parish, LA Trial plantings of cedar 1990, John Bennett Road off McCoy and others 2003 

Hwy 36.
48

Although cedar seedlings can survive a few years in shaded 

conditions, they will eventually die if they are not in a canopy 

gap and exposed to direct sunlight (Korstian and Bush 1931, 

Laderman 1989). 

At the Camp Shelby site, competing woody vegetation 

included loblolly pine, slash pine, red maple, redbay, large 

gallberry, and sweetleaf. Loblolly pine and cedar were the 

tallest trees in the canopy at about 25 to 35 m tall. A thick 

shrub layer and extensive growth of large smilax vines 

made walking difficult in some areas. Cinnamon and royal 

ferns were present in the herbaceous layer. This site had 

an organic soil and a well developed litter layer of mixed 

needles and broad leaves. The stream channel was braided 

with very moist soils and pooled water. Like many other 

cedar sites we have visited, there was evidence of shallow 

flooding with standing water in depressions. One part of the 

site was subjected to long periods of standing water and was 

characterized by numerous dead cedars, many still standing, 

and extensive amounts of cedar regeneration. Many of the 

cedar trees occurred in small clusters of variable size. This 

clustering of cedar suggests gap phase dynamics occurred 

on this site, probably as a result of the dying trees creating 

canopy gaps. Two clusters of cedar about 15 m apart consist 

of 6 to 10 individuals each. The diameters of the individual 

cedars ranged from 7.7 to 62.8 cm d.b.h. and they were 25 

to 30 m tall. The largest cedars noted during this visit may 

represent the largest cedars in Mississippi. 

The Camp Shelby stand represents our northernmost known 

location for cedar in Mississippi. The stand is unusual in that

it is so far inland, about 60 km more than the other Mississippi

stands. Five cedar stands in Georgia are also far inland at > 

225 km from the coast. These stands are found along the fall 

line in the sandhills of western Georgia (Sheridan and others 

1999, Sheridan and Patrick 2003). The presence of these 

stands at such great distances from the coast is encouraging 

and suggests that other cedar stands may exist farther north 

in Alabama and Mississippi. Another stand of cedar on Camp 

Shelby was rumored to have existed, but it was probably 

destroyed by the installation of a shooting range.

Two planted populations of cedar are known to exist along 

the gulf coast (McCoy and others 1999, 2003). These stands 

were planted to study the restoration and growth potential of 

Figure 1—General locations of known sites of Atlantic white cedar listed in table 1. Some dots may cover 

more than one site. 

Figure 2—Range map of counties with cedar within Mississippi, 

Alabama, Georgia, Florida and Louisiana cedar plantations. This 

map shows the counties, in gray, associated with the cedar locations 

described in table 1.
49

Table 2—Plants observed at individual Mississippi locations from table 1. These observations are compiled from Mississippi Museum of Natural History 

unpublished data, journal articles or personal observations as noted in table 1. The time of each observation varies seasonally as well as by year. No comparison between sites is intended. Data in columns A through O refers to specific locations, given in table 1, where each listed species was found

Group and family Species Common name A B C D E F G H I J K L M N O

FORBSAlismataceae Sagittaria lancifolia L. Bull tongue arrowhead X Alismataceae Sagittaria latifolia Willd. Duck-potato X X Asclepiadaceae Cynanchum angustifolium Gulf coast swallow X 

Asteraceae Eupatorium L. Boneset X 

Asteraceae Carphephorus odoratissimus Vanilla leaf X 

 (J.F. Gmel.) Herbert 

Asteraceae Solidago sempervirens L. Seaside goldenrod X X X 

Bromeliaceae Tillandsia usneoides (L.) L. Spanish moss X 

Iridaceae Iris virginica L. Virginia blueflag X 

Sarraceniaceae Sarracenia L. Pitcherplant X 

Saururaceae Saururus cernuus L. Lizard’s tail X 

GRASSES AND SEDGESCyperaceae Cladium mariscus ssp. Jamaican grass X X X X X X X X 

Jamaicense (Crantz) Kükenth.

Cyperaceae Scleria Berg. Nut rush X 

Juncaceae Juncus roemerianus Scheele Needle grass rush X 

Poaceae Arundinaria gigantea (Walt.) Giant cane X 

 Muhl.

Poaceae Dichanthelium (A.S. Hitchc. Rosette grass X 

 & Chase) Gould

Poaceae Panicum virgatum L. Pers. Wand panic grass wort X X 

SHRUBSAquifoliaceae Ilex coriacea (Pursh) Chapman Large gallberry X X X X X 

Aquifoliaceae Ilex glabra (L.) Gray Inkberry X 

Aquifoliaceae Ilex vomitoria Ait. Yaupon X X X X X X X 

Arecaceae Sabal minor (Jacq.) Pers. Dwarf palmetto X X X Arecaceae Serenoa repens (Bartr.) Small Saw palmetto X X 

Asteraceae Baccharis halimifolia L. Eastern baccharis X 

Betulaceae Alnus serrulata (Ait.) Willd. Brookside alder X Betulaceae Alnus P. Mill. Alder X 

Calycanthaceae Calycanthus floridus L. Sweetshrub 

Calycanthaceae Calycanthus floridus L. Eastern sweetshrub X X 

Caprifoliaceae Viburnum nudum L. Possumhaw X XClethraceae Clethra alnifolia L. Coastal sweet pepperbush X 

Cyrillaceae Cliftonia monophylla (Lam.) Buckwheat tree, X X X X 

Britt. ex Sarg. Black titi 

Cyrillaceae Cyrilla racemiflora L. Swamp titi X X X X X

(continued)
50Table 2—Plants observed at individual Mississippi locations from table 1. These observations are compiled from Mississippi Museum of Natural History 

unpublished data, journal articles or personal observations as noted in table 1. The time of each observation varies seasonally as well as by year. No comparison between sites is intended. Data in columns A through O refers to specific locations, given in table 1, where each listed species was found (continued)

Group & family Species Common name A B C D E F G H I J K L M N O

SHRUBS (cont.)Ericaceae Lyonia lucida (Lam.) K. Koch Shinyleaf X 

Ericaceae Gaylussacia mosieri Small Wolly huckleberry 

Ericaceae Kalmia latifolia L. Mountain-Laurel X X 

Ericaceae Lyonia Nutt. Staggerbush 

Ericaceae Rhododendron L. Azalea X X X X Ericaceae Vaccinium arboreum Marsh. Tree Sparkleberry X X 

Ericaceae Vaccinium elliottii Chapman Elliott’s blueberry X X X 

Ericaceae Vaccinium L. Blueberry X 

Ericaceae Vaccinium stamineum L. Deerberry X X 

Fabaceae Amorpha fruticosa L. False indigo bush X 

Grossulariaceae Itea virginica L. Virginia sweetspire X X 

Hamamelidaceae Hamamelis virginiana L. American witch hazel X X Illiciaceae Illicium floridanum Ellis Florida anisetree 

Lauraceae Cinnamomum camphora (L.) J. Camphor tree X 

 Presl

Myricaceae Morella inodora (Bartr.) Small scentless bayberry X X 

Myricaceae Morella cerifera (L.) Small Wax myrtle X X X X X X 

Rosaceae Photinia pyrifolia (Lam.) Red chokeberry

Robertson & Phipps X X 

Styracaceae Styrax americanus Lam. American snowbell X X TREES Aceraceae Acer rubrum L. Red maple X 

Aceraceae Acer rubrum var. drummondii Swamp red maple X X X X X X X X 

 (Hook. & Arn. ex Nutt.) Sarg.

Anacardiaceae Toxicodendron vernix (L.) Poison Sumac X X 

 Kuntze 

Aquifoliaceae Ilex Opaca Ait. American holly X 

Arecaceae Sabal palmetto (Walt.) Lodd. Cabbage palmetto X 

 Ex J.A. & J.H. Schultes

Cornaceae Nyssa biflora Walt. Swamp tupelo X X X X X X X XCornaceae Nyssa sylvatica Marsh. Black tupelo X 

Cupressaceae Chamaecyparis thyoides (L.) Atlantic white cedar X X X X X X X X X X X X X X X 

 B.S.P.

Cupressaceae Taxodium ascendens Brongn. Pond cypress X X X X X X Cupressaceae Taxodium distichum (L.) L.C. Baldcypress X X 

 Rich.

Euphorbiaceae Triadica sebifera (L.) Small Chinese tallowtree X X X 

Fagaceae Castanea P. Mill. Chestnut 

(continued)
51

Table 2—Plants observed at individual Mississippi locations from table 1. These observations are compiled from Mississippi Museum of Natural History 

unpublished data, journal articles or personal observations as noted in table 1. The time of each observation varies seasonally as well as by year. No comparison between sites is intended. Data in columns A through O refers to specific locations, given in table 1, where each listed species was found (continued)

Group and family Species Common name A B C D E F G H I J K L M N O

TREES (cont.)Fagaceae Quercus hemisphaerica Bartr. Darlington’s oak X 

 ex Willd.

Fagaceae Quercus minima (Sarg.) Small Dwarf live oak X 

Fagaceae Quercus nigra L. Water oak X X X X X 

Fagaceae Quercus pumila Walt. Running oak X 

Hamamelidaceae Liquidambar styraciflua L. Sweetgum X 

Juglandaceae Carya Nutt. Hickory X 

Magnoliaceae Liriodendron tulipifera L. Tulip tree X Magnoliaceae Magnolia grandiflora L. Southern magnolia X X X Magnoliaceae Magnolia virginiana L. Sweet bay X X X Oleaceae Fraxinus caroliniana P. Mill. Carolina Ash X X Oleaceae Osmanthus americanus (L.) Devilwood X X 

 Benth. & Hook. f. ex Gray

Pinaceae Pinus elliottii Engelm. Slash pine X X X X X X Pinaceae Pinus palustris P. Mill. Longleaf pine X X Pinaceae Pinus taeda L. Loblolly pine X X Rutaceae Zanthoxylum clava-herculis L. Hercules’club XSalicaceae Salix nigra Marsh. Black willow X VINESAnacardiaceae Toxicodendron radicans (L.) Kuntze Eastern poison ivy X X X X X X 

Caprifoliaceae Lonicera japonica Thunb. Japanese honeysuckle X 

Fabaceae Wisteria frutescens (L.) Poir. American wisteria X 

Rhamnaceae Berchemia scandens (Hill) K. Koch Alabama supplejack X Smilacaceae Smilax glauca Walt. Sawbrier X Smilacaceae Smilax L. Greenbrier X X Smilacaceae Smilax rotundifolia L. Horsebrier X X Vitaceae Vitis aestivalis Michx. Summer grape X Vitaceae Ampelopsis arborea (L.) Koehne Peppervine X X Vitaceae Parthenocissus quinquefolia Virginia creeper X 

 (L.) Planch.

Vitaceae Vitis rotundifolia Michx. Muscadine X X FERNSBlechnaceae Woodwardia areolata (L.) T. Netted chain fern X 

 Moore

Dennstaedtiaceae Pteridium aquilinum (L.) Kuhn Northern bracken fern X 

Osmundaceae Osmunda cinnamomea L. Cinnamon fern X X X X X X 

Osmundaceae Osmunda regalis L. Royal fern X X X X X X X X 

Shagnaceae Sphagnum Sphagnum X X X 
52

this species. One stand is located in a bayhead on the Bogue 

Chitto National Wildlife Refuge, northwest of Picayune, Pearl 

River County, MS. At this location, two small stands were 

established using wildlings collected at the Bluff Creek stand 

near Vancleave. After 11 years, survival at this site was only 

56 percent, but most of the mortality was in one stand that 

was situated along a small creek. The other cedar plantation,

in three small stands established during the spring of 1990 in 

the wetter areas of a slash pine plantation, is located near

Abita Springs, St. Tammany Parish, LA. Survival rate was 

very high at this site with 91 percent of the trees living through

10 growing seasons. The presence of cones as early as 1997

and of numerous seedlings in 2000 suggested vigorous 

stand development. Although most of the seedlings were 

small (< 25 cm), a few were 60 cm in height and were more 

than 8 m from the nearest possible parent tree.

Several additional locations of cedar have been mentioned 

in manuscripts, herbarium labels, field notes and/or the 

Mississippi Museum of Natural Science database http://www.

mdwfp.com/museum/ and range from single trees to small 

stands. Most of these sites are in Jackson County and 

include numerous scattered trees along the lower reaches 

of the Escatawpa and Pascagoula rivers and Bluff Creek. 

Generally, there were fewer than 25 individual cedar stems 

noted at these locations. Cedars at these sites range in 

height from 7 to 20 m. Competing vegetation included slash 

pine, red maple, redbay, baldcypress, Carolina ash, wax 

myrtle, yaupon, deerberry, and camphor tree (table 2). Some 

sites near the coast were adjacent to brackish water; where 

trees were perched on river banks above the water level. 

Additional Jackson County sites that the authors have not 

visited include Big Cedar Creek, the Escatawpa River at 

Highway 614, Goodes Mill Lake, and along Saracenia Road 

(table 1). 

Cedar sites in other counties include Juniper Grove (south 

of the Poplarville-Pearl River Airport, in Pearl River County), 

near the Highway 603 bridge over the Jourdan River (in 

Hancock County), and Juniper Bay and along the Escatawpa 

River near Highway 96 (in George County). These data 

indicate that at least five counties in southern Mississippi 

support individual trees or stands of cedar (fig. 2).

PLANT ASSOCIATIONS

Species listed in table 2 and noted in the text are not meant 

to be a comprehensive list of plant species found in the cedar 

stands discussed. As such, the list of plants for any given 

site should not be used to determine similarity or differences 

between locations. Table 2 represents a subset of plants that 

were casually observed during one visit to some Mississippi 

cedar sites, or from data taken from the Mississippi Museum 

of Natural History database, herbarium labels, and published 

papers. Species names are directly from the source (field 

notes, database listings, herbarium sheets, etc.), or in the 

case of our collections, from Kartesz and Meacham (1999). 

At this time, little significance can be given to plant associations listed in this paper. These results are presented as 

preliminary data for information purposes only. Only the 

study of Eleuterius and Jones (1972) consisted of a quantitative description of plant species associated with cedar, and 

that study was conducted only at Bluff Creek. More complete 

plant listings will be possible after a more complete inventory 

and analysis of these stands.

CONCLUSIONS

Little is known about the cedar stands along the gulf coast. 

With only one stand described in detail and just a few additional locations known for this species, the future of cedar 

in coastal Alabama and Mississippi is uncertain. This study 

has highlighted the location of several additional stands 

and many isolated trees. It appears that the species is not 

as rare along the gulf coast as previously thought. Many 

of the known stands, however, are degrading as a result of 

urbanization, erosion, land use and hydrologic changes in 

the surrounding landscape. As we continue to characterize 

selected stands, our knowledge of and our ability to predict 

the sustainability of the gulf coast cedar stands will improve.

ACKNOWLEDGMENTS

Information and assistance in the field was provided by 

Ronald Wieland of the Mississippi Natural Heritage Program 

and Mississippi Museum of Natural Science, and the staffs 

of the Grand Bay National Wildlife Refuge, the Mississippi 

Sandhill Crane National Wildlife Refuge, and the DeSoto 

National Forest. We would also like to thank Jim Allen and 

Marianne Burke for reviews of early versions of this manuscript.

LITERATURE CITED

Boyle, E.D.; Kuser, J.F. 1994. Atlantic white-cedar propagation by 

seed and cuttings in New Jersey. Tree Planter’s Notes 45(3): 

104-111.

Brown, C.A. 1938. Contributions to the Pleistocene history of the 

Florida Parishes of Louisiana. Geolog. Bull. 12. New Orleans: 

Department of Conservation. Louisiana Geological Survey. 70 p.

Carter, A.R. 1987. Cedar restoration in the dismal swamp of Virginia 

and North Carolina. In: Laderman, A.D., ed. Atlantic white cedar 

wetlands. Boulder, CO: Westview Press: 323-325.

Coulter, S. n.d. A catalogue of the flowering plants and of the ferns 

and their allies indigenous to Indiana. 521 p.

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wetlands and suburbanization: Effects on hydrology, water quality, 

and plant community composition. Journal of Applied Ecology. 28: 

467-490.

Eleuterius, L.; Jones, S.B. 1972. A phytosociological study of the 

white cedar in Mississippi. Castanea. 37: 67-79.

Givens, C.R.; Givens, F.M. 1987. Age and significance of fossil 

white spruce (Picea glauca). Tunica Hills, LA-MS: Quarternary 

Research. 27: 283-296.

Kartesz, J.T.; Meacham, C.A. 1999. Synthesis of the North American 

Flora, Version 1.0. Chapel Hill, NC: North Carolina Botanical 

Garden.

Korstian, C.F.; Brush, W.D. 1931. Characteristics, growth, and 

management of the forest. Southern white-cedar Tech. Bull. 251. 

Washington, DC: U.S. Department of Agriculture. 75 p.

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swamps: A review of techniques for propagation and establishment. 

Tree Planters’ Notes. 46: 78-85.

Laderman, A.D. 1987. Atlantic white cedar wetlands. Boulder, CO: 

Westview Press. 401 p.
53

Laderman, A. 1989. The ecology of the Atlantic white cedar wetlands:

a community profile. Bio. Rep. 85 (7.21). U.S. Fish and Wildlife 

Service. 114 p.

Little, S. 1950. Ecology and silviculture of white cedar and associated hardwoods in southern New Jersey. School of Forestry Bull. 

56. New Haven, CT: Yale University. 122 p.

McCoy, J.W.; Keeland, B.D.; Allen, J.A. 1999. Atlantic white cedar 

plantings, St. Tammany Parish, Louisiana, and the Bogue Chitto 

National Wildlife Refuge, Mississippi. In: Shear, T.H.; Summerville, 

K.O., eds. Atlantic white cedar: ecology and management symposium. Gen. Tech. Rep. SRS–27. Asheville, NC: U.S. Department 

of Agriculture, Forest Service, Southern Research Station: 36-41.

McCoy, J.W.; Keeland, B.D.; Allen, J.A. 2003. Atlantic white cedar 

beyond the western edge of its normal range. In: Atkinson, R.B.;

Belcher, R.T.; Brown, D.A.; Perry, J.E., eds. Atlantic White Cedar

Restoration Ecology and Management: Proceedings of a symposium. Newport News, VA: Christopher Newport University: 263-270.

Messina, M.G.; Conner, W.H., eds. 1998. Southern forested wetlands:

Ecology and management. Boca Raton, FL: Lewis Publishers/

CRC Press. 616 p.

Mohr, C. 1901. Plant life of Alabama. Contr. U.S. Nat. Herb. No. 6. 

921 p.

Patterson, H.N. 1876. Catalogue of the phaenogamous and vascular 

cryptogamous plants of Illinois, native and introduced. “Spectator” 

Print. 54 p.

Schaffner, John H. 1932. Revised catalog of Ohio vascular plants, 

arranged according to the phyletic system of classification; with 

notes on the geographic distribution in the State, based mainly 

on specimens in the Ohio State Herbarium of the Ohio State 

University. Columbus, Ohio: The Ohio State University. 215 p.

Sheridan, P.; Orzell, S.; Bridges, E. 1999. Some noteworthy 

vascular plant records from Atlantic white cedar, Chamaecyparis 

thyoides (L.) B.S.P., habitats of western Georgia. In: Shear, 

T.H.; Summerville, K.O., eds. Atlantic white cedar: ecology and 

management symposium. Gen. Tech. Rep. SRS–27. Asheville, 

NC: U.S. Department of Agriculture, Forest Service, Southern 

Research Station. 82 p.

Sheridan, P.S.; Patrick, T.S. 2003. A rate plant survey of Atlantic 

white cedar, Chamaecyparis thyoides (L.) B.S.P., habitats of the 

Georgia west-central fall line sandhills. In: Atkinson, R.B.; Belcher, 

R.T.; Brown, D.A.; Perry, J.E., eds. Atlantic white cedar restoration 

ecology and management: Proceedings of a symposium. Newport 

News, VA: Christopher Newport University.

Ward, D.B.; Clewell, A.F. 1989. Atlantic white cedar (Chamaecyparis 

thyoides) in the Southern States. Florida Scientist. 52: 18-47.

Zhu, W.X.; Ehrenfeld, J.G. 1999. Nitrogen mineralization and 

nitrification in suburban and undeveloped Atlantic white cedar 

wetlands. Journal of Environmental Quality. 28: 523-529. 
54

INTRODUCTION 

Atlantic white cedar [Chamaecyparis thyoides (L.) B.S.P.] 

(AWC) is an evergreen, wetland tree species that inhabits 

peatlands along the Atlantic and Gulf coasts of the United 

States. In the past 200 years most of the historic peatlands 

along the eastern seaboard of the United States have been

destroyed. The remaining peatlands and their adjacent uplands

harbor an inordinately large number of rare, threatened and 

endangered plant and animal species (Laderman 1989). 

Some of these species are found only in cedar swamps 

(Cryan 1985). AWC may be considered globally threatened 

as a species or as a community type (McAvoy and Clancy 

1993), and has been reduced to < 2 percent of its original 

acreage (Noss and others 1995). 

AWC survives only under a very narrow set of environmental 

conditions (Laderman 1989, 2003). Rainwater that falls in 

the sandy uplands in landscapes above AWC wetlands is 

slowly released over confining soil layers, or at sea level as 

ex filtrating groundwater seepage. Plants such as Sphagnum 

mosses and emergent hydrophytes colonize these wet, sandy,

mineral soils and over a number of years form an organic 

peat substrate. Wetland vegetation associated with these 

areas is typically well adapted to low pH conditions. Peat will

also frequently accumulate along the edges of adjacent open

water habitats. Associated water impoundments, such as

spring-fed ponds, sometimes develop floating mats of peat as

water lilies (Nymphaea odorata Ait.) and other species create 

organic material faster than it decomposes. Eventually, 

species including sedges and Sphagnum mosses colonize

these peat mats and form hummocks that are suitable microhabitats for the establishment of AWC seedlings. Close 

investigation of sites now containing AWC on organic soils 

revealed that seepage wetlands are associated with suitable 

habitat for this species. 

In Maryland, AWC occurs on peat that has formed on sandy 

seepage wetlands along the edges of bogs, ponds, streams, 

and tidal headwaters of the Chesapeake Bay (Hull and 

Whigham 1987). The species was once abundant within the 

predominantly deciduous tidal swamps along the major rivers 

of the eastern shore of the Chesapeake Bay (Dill and others 

1987, Shreve and others 1910). In Anne Arundel County, 

Maryland, a series of peatland complexes occurs along a 

narrow band of sandy, acidic soils of the Magothy Geologic 

Formation (Kirby and Matthews 1973). Where these soils 

surface at or near sea level along the shores of the Severn 

and Magothy Rivers, groundwater discharges and peatlands 

develop. Ten of these peatlands contain the only known 

remaining wild populations of AWC on the western Coastal 

Plain of Maryland (WCPMD) and represent the western edge 

of the range of the species in Maryland. Sheridan and others 

(1999) found that AWC occurred in nine sites containing 

a cumulative total of 1,214 living trees > 1.2 m in height 

remaining on the WCPMD. A 10th site containing < 100 trees 

was found in 2000 and has subsequently been reduced to 

less than 20 trees. These inventories indicated declining 

populations and resulted in investigations of potential sites 

for AWC conservation, restoration, and recovery opportunities to ensure the continued existence of AWC and other 

peatland species in Anne Arundel County. 

ATLANTIC WHITE CEDAR SPECIES RECOVERY AND

WETLAND ENHANCEMENT PROJECT AT HOWARD’S BRANCH,

ANNE ARUNDEL COUNTY, MARYLAND

Keith R. Underwood, William B. Moulden,

Dennis C. McMonigle and David J. Wallace1

1 Keith R. Underwood, Ecologist, 1753 Ebling Trail, Annapolis, MD 21401; William B. Moulden, Director, Sherwood Forest Naturalist Program, 

290 Nottingham Hill, Sherwood Forest, MD 21405; Dennis C. McMonigle, Environmental Programs Engineer, Department of Public Works, Anne 

Arundel County, 2662 Riva Road, Annapolis, MD 21401; David J. Wallace, Professional Engineer, 701 Chesapeake Avenue, Annapolis, MD 

21403. 

Citation for proceedings: Burke, Marianne, K.; Sheridan, Philip, eds. 2005. Atlantic white cedar: ecology, restoration, and management: 

Proceedings of the Arlington Echo symposium. Gen. Tech. Rep. SRS-91. Asheville, NC: U.S. Department of Agriculture, Forest Service, 

Southern Research Station. 74 p.

Abstract—The creation of a new site for Atlantic white cedar [Chamaecyparis thyoides (L.) B.S.P.] was the driving force 

behind a stream stabilization and wetland enhancement project in Anne Arundel County, MD. The Howard’s Branch project 

was designed to create peatland ecosystems in a highly degraded stream valley flood plain by creating a functional seepage 

wetland supporting a sustainable Atlantic white cedar community. A series of cobble weirs and a network of sand berms were 

placed over a dry lakebed to simulate the geology and hydrology found in natural Atlantic white cedar sites. In April 2001, 

construction of the project was completed with the planting of 1,000 Atlantic white cedars propagated from the 10 remaining 

stands of the species on the western Coastal Plain of Maryland. This paper reviews the procedures developed for the 

Howard’s Branch project, reports on the status of the constructed wetland, and discusses the regulatory hurdles that were 

encountered. 

Keywords: Bog, Chamaecyparis thyoides, forested wetlands, seepage wetlands, stream restoration. 
55

METHODS 

Project Site Selection 

In the fall of 1997 sites were evaluated for their potential for 

the establishment of a new AWC population to make up for 

historic and recent losses. The leading experts in AWC restoration were consulted before and during the undertaking of 

this project. A 3 acre dry lakebed on a tributary of the Severn 

River known as Howard’s Branch was selected due to factors 

weighing in its favor to provide a suitable base for creation of 

a seepage wetland with AWC, including: its general topography, the constant water flow through the site, its proximity 

to remnant AWC populations (fig. 1), its position in the landscape, the accessibility for equipment and the willingness of 

landowners to host the project. 

Site History 

In 1930, a forested stream valley flood plain was flooded to a

depth of -4 feet with the construction of an earthen dam across

a small stream known as Howard’s Branch. The resulting 

lake was the sole drinking water supply for the community of

Sherwood Forest until 1970. In 1980 the dam failed and the 

lake drained, exposing sediments that had accumulated 

behind the dam over 50 years. The stream subsequently cut

through those sediments, which were then transported downstream to tidal waters, damaging tidal and sub-tidal ecosystems, and resulting in disturbance regime plants such as 

common reed (Phragmites australis) in the tidal wetlands 

and Eurasian water-milfoil (Myriophyllum spicatum) in the 

adjacent shallow tidal waters. 

Physical Conditions 

Stream characteristics—Howard’s Branch is approximately 

one mile long from its headwaters to its outflow into Brewer 

Creek. The stream begins as toe slope seepage from two 

upper reaches of the ravine system, wherein it converges into

one main stream channel just above the project site. The 

remnants of the dam are located 1,000 feet upstream of a

pond at the tidal interface with Brewer Creek, a tributary of the

Severn River. The Howard’s Branch stream valley floodplain 

(former impoundment) within the project site is approximately

737 feet long and 120 feet wide. The floodplain ranges in elevation between 10 and 15 feet above sea level. The drainage 

area to the project site is a total of 231 acres, or 0.4 square

miles, and is comprised of a mix of forested open space and 

low density residential. The base flow of the stream through 

the project site is about 2 cubic feet per second. 

Soils—Surface soils within the project area are generally 

comprised of mixed alluvial deposits that range from clay 

to sand (Kirby and Matthews 1973). These soils have been 

deposited in the former impoundment from various upstream 

eroding soils. The stream valley flood plain is generally level, 

with a slope of < 1 percent. The soils are poorly drained and 

remained wet even in dry periods. The soils surrounding the 

project area are Monmouth fine sandy loam, with a slope 

of 15 to 40 percent, which overlays the white sands of the 

Magothy Formation. Within the Monmouth mapping unit are 

some deep gullies that have a very sandy or silty surface 

layer, and the slopes are highly susceptible to erosion when 

existing vegetation is removed (Kirby and Matthews 1973). 

Figure 1—Locations of all known Atlantic white cedar populations west of the Chesapeake Bay.
56

Preproject Environmental Conditions 

Wetlands—The project area was dominated by nontidal 

wetlands surrounded by steep slopes. The site was predominantly characterized as an open wet meadow dominated by 

rice cut-grass (Leersia oryzoides), Asiatic tearthumb/milea-minute vine (Polygonum perfoliatum L.), joe-pye weed 

(Eupatorium dubium Willd.), boneset (Eupatorium perfoliatum L.), and goldenrod (Solidago sp.). A small amount of 

sphagnum (Sphagnum sp.) was present. 

Woody species included smooth alder (AInus serrulata Ait. 

Willd), which formed a mature stand consisting of about 20

large individuals standing 30 feet apart at the upper end of the

project site. Sweet gum (Liquidambar styraciflua L.) formed a

small stand of perhaps 50 individuals up to 4 inches diameter

at breast height (DBH) on the north side of the site at the 

confluence of a forested ravine. Eleven mature red maples 

(Acer rubrum L.) up to 11 inches DBH were mapped at the 

uppermost end of the flood plain and also formed a small 

stand of trees up to 4 inches DBH at the lower end of the 

project site. The site was generally wetter near the upper 

end and drier near the downstream end in the vicinity of the 

remaining portion of the earthen dam. 

Uplands—The watershed contains a low density residential 

community on the south side and a 100 year old forest under 

a conservation easement on the north side. The drainage area

consists primarily of steep slopes that grade up to 120 feet 

in elevation. About 80 percent of the uplands are currently 

forested with a mixed hardwood canopy, including oak 

(Quercus sp.) and American beech (Fagus grandifolia Ehrh.), 

with a minor Virginia pine (Pinus virginiana) softwood component and a mountain laurel (Kalmia latifolia L.) understory. 

Planning and Permits 

The project was designed to simulate the geology and hydrology found in the remaining native AWC sites. A fill operation 

was designed and permitted, resulting in the establishment 

of a seepage wetland that supports a viable population of 

AWC. 

Flow rates for various storm events at Howard’s Branch were

determined using calculations derived from the Soil Conservation Service “Urban Hydrology for Small Watersheds” 

Technical Release (TR) 55 (U.S. Department of Agriculture 

1986). The Anne Arundel County soil survey maps (Kirby and

Matthews 1973) were also consulted to develop the calculations. Current land use results in a runoff curve number (RCN)

of 70, while the ultimate development based on existing zoning

results in a RCN of 77. The time of concentration—the time 

for rainwater runoff to travel from the hydraulically most 

distant point of the watershed to a point of interest within the

watershed—for both existing conditions and ultimate buildout based on current zoning was calculated to equal 1.15 

hours. A conservative approach from the Seelye (1960) design

manual and Harr (1990) was used to determine the capability for the capillary potential of sand to wick water toward 

the surface. This information was used to design the project 

features. 

Plans were designed to physically alter the lakebed and 

incised stream channel in relationship to existing hydrologic

characteristics. The project was designed to capture and 

redirect base flows to maximize irrigation of the berms 

while redirecting and reducing the energy associated with 

large storm flows allowing excess water to pass harmlessly 

through the site. The plans were submitted to the regulatory

authorities, and the U.S. Army Corps of Engineers and 

Maryland Department of the Environment issued permits 

for temporary impacts to 125,389 square feet (2.88 acres) 

of existing nontidal wetlands and 737 linear feet of stream 

channel. 

Construction 

A series of seven cobble weirs were constructed across the 

main stream channel about 100 feet apart in 1 foot lifts as 

grade controls. Each weir flooded the soils above it, including 

the incised eroding stream channel, resulting in water retention, creation of sheet flow, and reduction in velocities of storm

water passing through the project site. The weir structures 

were reinforced with the placement of sandstone boulders 

at the toe of each weir. The subsequent colonization of the 

weirs by vegetation was intended to further improve their 

stability. 

A network of berms, comprised of sand, gravel, and wood 

chips about 3 feet thick and 40 feet wide, was combined with 

the cobble weirs to form a new surface topography that would 

control surface and subsurface hydrology (fig. 2). Hydrology 

for the sand berms was provided by lateral seepage of water 

from the moats and capillary action, resulting in increased 

and stabilized soil moisture levels. The berms were designed 

to serve as temporary haul roads by placing a single 12 foot 

wide strip of poly-woven geotextile in the design locations of 

the future berms. 

The sand berms were placed about ten feet from the toes of

the adjacent steep slopes flanking the northern and southern 

sides of the project site. The resulting depressions between 

the tops of the berms and the adjacent side slopes serve to

capture surface water and ground water seepage from the

side slopes, which formed long pools (moats) that surrounded

most of the site (fig. 3) .The water surface elevation in the 

moats was designed to be up to 3 feet higher than the water 

surface elevation in the channel. Water captured in the moats 

would then move laterally and irrigate the sand berms. As 

water slowly filters through the sand berms to lower elevations, sandy seepage slopes are created similar to those 

found in other AWC sites. The sand berms were placed to 

meet the edge of water impoundments created by the weirs 

in the stream channel. 

Six thousand tons of white, bank-run silica sand and gravel 

were used to form the berms and 1,000 tons of sandstone 

(ferracrete) boulders were used as grade controls for the 

weirs and the lower stream channel. One hundred cubic yards

of Virginia pine and red maple wood chips were trucked into 

the site. One hundred four cubic foot bales of Canadian peat 

were placed on the site and exposed to rain a month before 

planting of the trees. One thousand tons of processed white 

silica sand (white play sand) was placed on the surface of 

the berms to preclude the establishment of red maple and 

sweet gum, undesirable plant species that require nutrients 

not available in pure sand. 
57

The last 50 feet of the lower end of the stream channel needed

to match up with the level of the undisturbed channel on the 

adjacent downstream property. The stream was incised 5 feet 

below the adjacent flood plain with eroding vertical banks. 

The channel was filled with bank-run gravel. Geo-textile was 

then placed over the gravel, and native sandstone boulders 

weighing up to 2 tons were used to line the channel to create 

a stable configuration for the new, steeper gradient. 

Construction access into the project site was achieved by 

shaping a wedge of bank-run gravel to form a ramp into the 

project site over a storm drain pipe system. The drain pipe 

and three drop structures were filled with gravel, which would 

treat storm water from a 10 acre drainage area that had 

previously discharged as untreated storm water into the site. 

This technique allowed some storm water to filter into the site 

as ground water. Upon departure from the site, the access 

ramp was reshaped to form a pedestrian pathway. 

Vegetation 

Two schoolyard wetlands were constructed specifically to 

propagate indigenous AWC stock for this project. Seed 

and cuttings were collected from all ten of the remaining 

wild populations west of the Chesapeake Bay. The seed 

and cuttings were used to propagate trees in the schoolyard wetlands and the Anne Arundel County greenhouse. 

Meadowview Biological Research Station in Woodford, VA 

also generated seedlings from the Arlington Echo native 

population as part of another study. The schoolyard wetlands 

were then used as grow out areas for the potted cedars. 

Following construction in April, 2001, one thousand Anne 

Arundel County-native AWC were planted as containerized 

saplings up to 48 inches in height on the sand berms by 

volunteers including school children, community members, 

politicians, and representatives of universities, research 

organizations, regulatory agencies and civic associations. 

Some plant species associated with AWC were subsequently 

introduced to the site from local native sources. 

Figure 3—Howard’s Branch typical cross section drawing.

Figure 2—Howard’s Branch as-built drawing.

1" = 250'

Sand berms

Shallow water

Seepage pools Cobble weirs

Stream
58

In a variation on techniques used by Haas and Kuser (1999)

that resulted in the best growth of AWC in a sterile sand site

with appropriate hydrology, we used peat, wood chips and

Osmocote® as soil amendments during planting. Subsequently,

the cedars were fertilized with half strength Miracid® three 

times in 2001 and twice in 2002. One handful of Holly tone®

was also applied to the base of each tree in August of 2002. 

Regeneration of AWC is hindered by browsing of white-tailed

deer (Odocoileus virginiana) and other herbivores, a problem

that is widely recognized throughout the range of AWC 

(Hinesley and others 2003, Kuser and Zimmermann 1995, 

Laderman 1989, Little and Somes 1965). Herbivore exclusion

cages were constructed of 12 gauge, 4-inch grid, galvanized 

wire fencing, secured into the ground with a single piece of 

6 foot long No. 6 rebar woven through the fencing and driven 

2 feet deep into the soil, resulting in a 48 inch high cage. 

Cages were placed around approximately 80 percent (800) 

of the planted AWC saplings. 

Groundwater monitoring wells were installed at various locations across the project site prior to construction. Twelve 

36-inch lengths of PVC pipe were installed to depths of 

about 24 inches. Photographic documentation of the project 

features and some of the organisms as well as groundwater 

to surface depth data was collected once every 2 weeks 

during the growing season prior to construction and each 

year following construction of the project. 

Grab samples of water leaving the site were collected once 

each year and sent to Phase Separation Sciences laboratory in Baltimore, MD for analysis of pH, dissolved oxygen, 

nitrogen, nitrate, ammonia, phosphorus and turbidity concentrations. A field run topographic survey of the entire project 

site was also conducted each year. Soil profiles from borings 

near the groundwater monitoring wells were described using 

the Munsell soils charts. 

RESULTS 

General Description 

We converted an eroding wetland dominated by non-native 

and invasive plant species to a stable seepage wetland 

complex supporting a number of threatened plant species. 

Construction of the project resulted in temporary impacts to

89,810 square feet (2.06 acres) of regulated, existing nontidal

wetlands and 737 linear feet of stream channel. Wetland 

enhancement was achieved on 47,266 square feet of emergent wetlands in shallow flooded areas and 42,264 square 

feet of forested wetlands on the sand berms. An additional 

280 square feet of stream channel was stabilized at the 

outfall. The area that was left undisturbed was 35,079 square 

feet. 

Topography 

The new topography formed by capping the flood plain with 

sand berms and cobble weirs remains stable in its designed 

position. Erosion of the stream banks was prevented, as was 

the subsequent loading of sediments into the downstream 

tidal water ecosystem of the Chesapeake Bay. 

Hydrology and Hydrogeology 

The constructed berms and weirs slow and retain base flow

surface waters while allowing a non-erosive course for surface

waters generated by storm events. Vegetation growing on 

the weirs has restricted the channel width over the weirs 

and created water depths of approximately 6 inches, which 

is adequate for passage of local fish species. Surface water 

flows are directed into a broad, flat, and gentle meandering 

pattern. Water captured in the moats and retention of water 

above the weirs serves both to raise and to stabilize the 

groundwater table and irrigate the berms. 

Groundwater has been maintained within 12 inches of the 

surface of the sand berms at all monitoring well locations for 

3 years with the exception of two wells in 2002 following a 

3-year drought. The irrigation moats (seepage pools) flanking 

the berms remained full with the exception of the highest 

pool, which was dry for a week in 2002 during a drought. The 

sand berms are wet to the surface through capillarity and the 

lateral seepage of water from the irrigation moats through 

the sand. Most of the former lake bottom is now perennially 

submerged under 1 to 18 inches of water. 

The base flow of the stream is now slowed and distributed 

to maximize the irrigation of the sand berms, while energies 

associated with storm flows are adequately dissipated by the

project features to allow the water to pass harmlessly through

the site. The project will also reduce the peak flows associated

with storm events and will slowly release the storm water as 

base flow to the stream. 

Vegetation 

One hundred seventy-seven vascular plant species were 

identified in the site by William S. Sipple in 2003 (appendix 1).

Using Reed (1988) to determine the wetland indicator status,

34 percent of the identified species are obligate wetland 

plants and 72 percent are facultative or wetter. AWC is now 

the dominant tree on the project site. The average DBH was

1 inch in 2003, and the canopy diameter averaged 34.6 inches.

The planted cedars have grown from an average of 2 feet in 

height to a range of between 6 and 12 feet tall. More than 50 

percent of the trees produced seed in 2003. Thousands of 

AWC seedlings resulting from natural recruitment range up 

to 16 inches in height. Utricularia sp. and American bur-reed 

(Sparganium americanum Nutt.) are dominant in the flooded 

areas. The herbaceous layer is dominated by yellow-eyed 

grass (Xyris torta Sm.) and the groundcover is dominated 

by American cranberry (Vaccinium macrocarpon Ait.) and 

Sphagnum sp. Algal mats are present on the surface of the 

wet sand. 

Soil Characteristics 

Soil characteristics have varied only slightly since the completion of the project although some wetness characteristics 

and redoximorphic features are evident in the created sand 

berms. Hydric soils require long periods of time for the 

development of wetness characteristics (Environmental 

Laboratory 1987). 

Water Quality 

Grab samples were collected just below the project site each 

year and sent for lab analysis. The pH of the water collected 

just below the project site has decreased from 6.54 in 2001 
59

to 5.60 in 2003. This may in part be due to the release of 

organic acids provided by decomposing vegetation. Pre- and 

post-construction nitrogen levels were not detectable at a 

concentration greater than or equal to the practical quantitative limit. The post construction level of phosphorus was 0.10 

ppm. 

Fauna 

Deer browse has not yet been a problem, and only a few 

trees have been damaged each year by deer scraping. In 

addition, over the 3 year period since construction, approximately 10 trees have been damaged or destroyed by beaver 

(Castor canadensis). Bullfrogs (Rana catesbiana), pickerel 

frogs (Rana palustris), green frogs (Rana clamitans), wood 

frogs (Rana sylvatica), American toads (Bufo americanus), 

spring peepers (Pseudacris crucifer), gray treefrogs (Hyla 

sp.) and spotted salamanders (Ambystoma maculatum) use 

the site for reproduction. Bluegills (Lepomis macrochirus) 

and pumpkinseeds (Lepomis gibbosus) have invaded the 

main channel from downstream, but have not made it into the 

moats. 

DISCUSSION 

We have observed considerable losses of dozens of peatland

species in the Atlantic Coastal Plain. These peatland ecosystems need active management, preservation and restoration.

Damaged ecosystems, e.g., Howard’s Branch, provide sites 

that “could be restored in such a way as to enhance the 

chances of survival for one or more rare, endangered, or 

threatened species” (Cairns 1986). Given the recent scientific 

documentation of the immense benefits provided by peatland 

ecosystems to tidal estuaries (Hinesley and Wicker 1999), 

restoration or establishment of new peatlands in created 

environments to make up for historic losses takes on a fresh 

urgency. 

Peatlands, including AWC swamps, become degraded when 

development and/or agriculture occurs within their drainage 

areas (Ehrenfeld and Schneider 1990, Laidig and Zampella 

1999). Without immediate efforts to appropriate habitat, 

manage storm water, and restore populations of peatland 

species, they will continue to disappear along with significant genetic variation within a number of species throughout 

their range. For instance, Benedict (in press) predicts the 

extinction of the fourth largest remaining AWC stand on the 

WCPMD in 2015. 

The resultant substrate for AWC at this site was most similar 

to the “extremely barren sand locations” at the lakeside site 

of Haas and Kuser (1999). It differed from other projects that 

attempted to restore AWC on former and/or degraded peatlands (Hinesley and Wicker 1999, Smith 1999). It is anticipated that the course growing medium, coupled with the 

creation of suitable habitat with relation to shade tolerance 

(Belcher and others 2003), planting survival (Brown and 

Atkinson 1999, McCoy and others 2003), natural regeneration (Eagle 1999, Zimmermann and others 1999) and competition with hardwoods (Eagle 1999) will produce the correct 

habitat for colonization by early successional species such 

as AWC. Accordingly, a peatland should develop as the AWC 

stand and its associated species produce organic material

more rapidly than it decomposes. The novel approach of 

creating seepage wetlands at Howard’s Branch could be 

used in other geographic areas to enhance the sustainability 

of other rare species dependent on this geomorphic setting. 

Aspects of the Howard’s Branch project were contested by

some individuals within the regulatory community. Key regulators stated that the site in its pre-project condition represented a stable, appropriately vegetated wetland, and further 

stated that the site represented the premium reference 

model for wetlands on the WCPMD. However, the authors 

documented erosion of the banks of the stream channel 

breaking away in series and falling into the channel at a rate 

of 1 cubic yard per week throughout the pre-construction 

monitoring period. The exposed sediments in the former 

impoundment allowed the colonization of invasive disturbance regime vegetation, mostly Asiatic tearthumb and rice 

cutgrass. Both are common species in disturbed wetland 

soils, and the tearthumb is a non-native weed. The few tree 

species on the site were locally abundant, including red 

maple and sweet gum. Some of the red maple, sweet gum, 

and alder died or showed stress from inundation, but alders 

in general have benefited from the project and increased 

in number and area covered. The subsequent erosion and 

deposition downstream also dictated occupation by the invasive species common reed at the tidal interface and Eurasian 

water- milfoil in the adjacent shallow tidal water. Downstream 

reaches are more stable now, and the AWC complex, which 

includes other rare plants, is a higher quality wetland than 

the system that was in the site. 

There was also a dispute as to whether the depth of sand 

placed to form the berms, and the amount of capillary movement of water through the sand, would result in wetlands or 

uplands. The depth to groundwater is an important aspect 

of creating appropriate habitat for AWC (Atkinson 2001, 

Harrison and others 2003, Mylecraine and others 2003). 

A conservative approach from the Seelye (1960) design 

manual and Harr (1990) was used to determine the capability for the capillary potential of sand to wick water toward 

the surface. However, the primary hydrology source for the 

berms was not only groundwater rising from below, but also

water moving laterally and downward from the higher elevation moats. Constant seepage through the sand berms 

creates similar irrigation to highly organic sites mentioned by 

Atkinson (2001), where the organic content modulated water 

table fluctuations. The sand berms on the Howard’s Branch 

site are wet enough to support algae growth on the surface 

and recruitment of obligate wetland plants is occurring. We 

not only believe that the sand berms will meet the definition 

of wetlands (Environmental Laboratory 1987), but that they 

will function as high quality wetlands for the long term. 

Finally, fisheries biologists opposed the issuance of the 

permits, despite the fact that electro-shocking showed that 

there were no fish in Howard’s Branch before the project was 

undertaken. They argued that the weirs would produce fish 

blockages and, therefore, the project would not benefit any 

fisheries resource. However, rains shortly after the project 

was completed raised the water level in the stream, and 

sunfish moved through the weirs and invaded the site. The 

fish have not invaded the moats, where they could reduce 

amphibian populations. 
60

Although AWC wetlands are a globally threatened ecosystem 

with < 2 percent of its historic acreage remaining and not a 

single intact AWC ecosystem remains in the State, it is listed 

by the Maryland Department of Natural Resources’ Heritage 

Program as an S-3 (State watch list) species and given no 

protection. State ranking is determined by the number of 

occurrences of any given species within the State. Historical 

evidence of former abundance exists, including excavated 

stumps and logs, local lore, site names and numerous 

personal communications, that indicates that the AWC forest 

dominated a large part of the landscape of the Cypress Creek

watershed 100 years ago. Dissection of that population 

occurred with the construction of a highway. The ensuing 

development adjacent to the highway caused the species 

to retreat to three small isolated locations. These remnants 

are now erroneously considered as three occurrences by 

the Maryland Department of Natural Resources’ heritage 

program. This splitting of sites does not accurately represent

the current rarity or the former importance of the AWC 

ecosystem type. 

A significant obstacle to ecological restoration can be the 

lack of ecological understanding by policymakers. Regulatory 

arguments against this project reflected limited knowledge 

of restoration ecology or habitat requirements for these 

organisms. For example, the reference sites used were 

highly degraded and represented refugia, not optimal habitat. 

The pre-restoration analysis in this project served to remind 

restoration ecologists and regulators of the importance of 

appropriately evaluating reference systems as models. There 

is a need to transfer technology such as that which was 

developed in this project to illustrate the value of restored 

wetlands and to distinguish between high quality and low 

quality wetlands. 

CONCLUSIONS 

The successful establishment of viable, reproducing populations of several rare wetland species at Howard’s Branch 

is an example of what can be accomplished given the will 

to act now while opportunities still exist. This 3 acre project 

at Howard’s Branch, from concept to construction, was 

achieved at a cost of less than $350,000. 

This project has demonstrated the feasibility of restoring 

and enhancing rare ecosystems using damaged sites; e.g., 

former impoundments, abandoned sand mines, stormwater 

management facilities and degraded wetlands, to create 

seepage wetlands in the absence of existing peatlands; of 

establishing a viable, reproducing population of AWC and 

associated species (a rare plant community) in a created 

seepage wetland; of designing criteria for establishment of 

functional AWC wetlands within the historic range; and of 

“Uniting Forces For Action” by actively engaging the public 

and promoting interest, awareness, education and stewardship. Similar projects should be undertaken wherever 

possible. 

ACKNOWLEDGMENTS 

Thanks to Bill and Patti Ferris who graciously allow use of

their property. This project was constructed by the Anne 

Arundel County Department of Public Works as a Capital 

Improvement Project with grants from the Maryland 

Department of the Environment and Natural Resources. 

Funding to construct wetlands at Millersville Elementary 

School and Samuel Ogle Elementary School was provided 

by the Chesapeake Bay Trust. The teachers and students at 

these schools propagated and planted AWC for the project. 

David Walbeck, Dennis Whigham, and Jeremiah Wentz 

provided substantial editing assistance. William Walton 

created the figures. 

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62

INTRODUCTION

In the late 1990s several previously unknown peatlands 

and one population of Atlantic white cedar [Chamaecyparis

thyoides (L.) BSP], (AWC) were discovered on a peninsula 

in Anne Arundel County, Maryland. The recently found 

peatlands include Main Creek Bog, discovered in 1998, and 

located in a millpond just above tidal waters. It supports a 

plant community that includes leatherleaf [Chamaedaphne 

calyculata (L.) Moench], round-leaved (Drosera rotundifolia L.) and spatulate-leaved (Drosera intermedia Hayne) 

sundews, white beakrush [Rhynchospora alba (L.) Vahl], 

and yellow-eyed grass (Xyris sp). The Maryland Avenue 

bog, discovered in 1999, resembles a “pitch pine pocosin” 

and includes sweet bay magnolia (Magnolia virginiana 

L.), pitch pine (Pinus rigida Miller), leatherleaf, pitcher 

plants (Sarracenia purpurea L.), cotton-grass (Eriophorum 

virginicum L.), and large cranberry (Vaccinium macrocarpon 

Aiton). The Dill Road AWC swamp was previously known as 

a part of the Cypress Creek AWC swamp. Recent documentation (Sipple 1999) now shows it as a fragmented, separate 

peatland. Unfortunately, this fragmentation and stormwater 

pollution have destroyed the rare species (pitcher plant, 

round-leaved sundew, and leatherleaf) and many of the large 

AWC trees. 

Description of Newly Found Bogs

In Anne Arundel County, there are 4,083 acres of watersheds

that contribute to bogs. These bogs and their watersheds 

have been identified and surveyed (fig. 1) and their ecological characteristics have been documented. All occur on the 

exposed sands of the Magothy geological formation (Kirby 

and Matthews 1973). These cretaceous sediments are 

composed of light colored, highly acidic sands interspersed 

with shallow aquacludes of clay or sandstone cemented with 

iron oxides and carbonates (Vokes 1957). The aquacludes 

direct rainfall through the sands into depressional areas. The 

resulting seepage has a pH of 5.5 to 3.7 and limits growth to 

plants that tolerate highly acidic conditions.

These peatlands commonly have histic soils; permanent, 

shallow inundation; a living Sphagnum (Sphagnum sp) layer;

and a community of acidophilic plants including sweet bay 

magnolia, pitcher plants, large cranberry, round-leaved and

spatulate-leaved sundews, leatherleaf, giant cane [Arundinaria gigantea (Walter) Chapman], cotton-grass, white 

beakrush, and yellow-eyed grass. 

Regulation of the Peat Bogs

The State of Maryland protects nontidal wetlands with the 

Nontidal Wetlands Protection Act of 1989 (Act), implemented 

on January 1, 1991. The Act and its code of Maryland regulations (Code of Maryland Regulations 2001) provide hierarchical levels of review and protection to nontidal wetlands 

based on their functions and values and the extent of the 

authorized impacts. 

Regulations stipulate that a 25-foot buffer must completely 

surround all nontidal wetlands. Alterations of < 5,000 square 

feet of nontidal wetlands with no significant plant or wildlife 

value receive an expedited review and authorization process. 

Nontidal wetlands with significant plant or wildlife value 

receive a higher level of regulatory protection, including the 

opportunity for the public to provide input. These wetlands 

include those located in cold water fishery watersheds; wetlands containing State and/or Federal rare, threatened or 

endangered plant and/or animal species; large, relatively 

intact wetlands; Atlantic white cedar, American larch [Larix 

laricina (Duroi) K. Koch], bald cypress [Taxodium distichum 

REGULATION AND PROTECTION OF PEATLANDS IN

ANNE ARUNDEL COUNTY, MARYLAND

Judy Broersma-Cole1

1 Judy Broersma-Cole, Wetlands Specialist, Maryland Department of the Environment, Wetlands Program, 800 Washington Blvd., Baltimore, MD 

21230.

Citation for proceedings: Burke, Marianne, K.; Sheridan, Philip, eds. 2005. Atlantic white cedar: ecology, restoration, and management: 

Proceedings of the Arlington Echo symposium. Gen. Tech. Rep. SRS-91. Asheville, NC: U.S. Department of Agriculture, Forest Service, 

Southern Research Station. 74 p.

Abstract—In the late 1990s several previously unknown peatlands and one population of Atlantic white cedar [Chamaecyparis

thyoides (L.) BSP], were discovered on a peninsula in Anne Arundel County, Maryland. At the request of the Anne Arundel 

County legislative delegation, the Maryland Department of the Environment revised its regulations to include the new peatlands on the list of Nontidal Wetlands of Special State Concern (NTWSSC), a special category of wetland. These wetlands 

have the highest degree of State regulatory protection, including an expanded 100-foot buffer. Subsequently, the Anne 

Arundel County bog committee (Committee) helped develop a county protection program and regulations were implemented 

including 100-foot, 300-foot and 1,000-foot limited development buffers in the contributory drainage areas. The Committee 

continues working to protect, preserve and restore the peatlands of Anne Arundel County, Maryland. This paper presents the 

new State and county regulations that attempt to protect these peatlands and focuses on the recent, rapid development of 

these regulations. 

Keywords: Anne Arundel County Bog Committee, Anne Arundel County, MD, Atlantic white cedar, Maryland Department of 

the Environment, peatlands, protection, regulation. 
63

(L.) Rich.], balsam fir [Abies balsamea (L.) Miller], and red 

spruce (Picea rubens Sarg.) swamps; vernal pools; Delmarva 

Bays; and peatlands, also known as bogs. The highest level 

of regulatory protection is assigned to Nontidal Wetlands of 

Special State Concern (NTWSSC). NTWSSC are defined in

regulation (Code of Maryland Regulations 2001) as “...having

exceptional ecological or educational value of Statewide 

significance.” If the wetland is a NTWSSC, the regulated 

buffer surrounding the wetland is expanded to 100 feet, affording additional protection for the rare species and uncommon, 

unique and/or unusual habitats. Alterations to the 100-foot 

wetland buffer require avoidance where feasible; minimization to the extent practicable; and the implementation of 

specific best management practices (BMPs) for sediment 

control and stormwater management where applicable. 

Because the newly discovered peatlands were not classified

as NTWSSC, they did not have the maximum 100-foot 

expanded buffer. 

Many NTWSSC have complexes of rare, threatened or 

endangered species and/or are uncommon wetland ecotypes 

including peatlands and AWC swamps. These NTWSSC are 

specifically listed, by name and United States Geological 

Survey quadrangle map, in the State regulations. Ten of the 

Anne Arundel County peatlands were included in the original 

regulations as NTWSSC. Two of these ten peatlands include 

populations of AWC. However, AWC is not listed as a rare 

species in Maryland and, therefore, wetlands with AWC are 

not necessarily NTWSSC.

These newly discovered bogs were not listed as NTWSSC in

regulation, and had only a 25-foot buffer and not the maximum

allowed. In December of 1999, at the request of the Anne 

Arundel County legislative delegation, the Maryland Department of the Environment was asked to include the newly 

discovered peatlands in the list of NTWSSC already in regulation. Subsequently, a group of State, and county agencies,

nongovernmental organizations, and interested citizens formed

the Anne Arundel County bog committee (Committee). 

The Committee was tasked with the identification, description,

mapping, and naming of the peatlands. The Committee meets

regularly to address peatland issues. It includes representatives from the Maryland Department of the Environment, 

Maryland Department of Natural Resources, Chesapeake Bay

Critical Areas Commission, U.S. Fish and Wildlife Service, 

U.S. Army Corps of Engineers, Anne Arundel Community 

College, Magothy River Land Trust, Severn River Association,

Anne Arundel County legislative delegation, Anne Arundel 

County council, Anne Arundel County government, Atlantic 

White Cedar Alliance, and local concerned citizens. 

As a result of regular meetings, workshops, and fieldwork, 

State emergency regulations were developed to include all 

of the nontidal wetlands on the Mountain Road peninsula as 

a system of interconnected peatlands. The regulations took 

effect in September of 2000 and mandated a 100-foot regulated buffer and specific BMPs for watersheds contributing to 

NTWSSC. The emergency regulations were formally adopted 

by the State legislature in January of 2001.

As a result of the Committee activities, the Anne Arundel 

County council passed legislation in 2002 to regulate 100-

foot, 300-foot, and 1,000-foot buffers in all known bog watersheds (County Council of Anne Arundel County, Maryland 

2002). Future development in these buffer areas will be 

Figure 1—Anne Arundel County bog protection area guidance map.
64

limited. No new development is permitted within the 100-foot 

buffer except minor (< 150 square feet) accessory structures 

to existing houses. No new development is permitted within 

the 300-foot regulated buffer except on existing legal lots; 

subdivision, stormwater management, and sewage treatment facilities are not permitted. New development is allowed 

within the 1,000-foot contributory drainage area under certain

conditions. Development in that area is permitted provided 

non-structural stormwater management practices with no 

direct discharge into a peatland are utilized; impervious 

surfaces are generally < 10 percent of the site area; < 20 

percent of forested areas are cleared; and established BMPs 

such as strict sediment controls and control of invasive plant 

species and yard waste are implemented.

The decision process for determining the appropriate State 

procedures for the regulation of nontidal wetlands in Anne 

Arundel County are outlined in Table 1. Regulations are 

from the Nontidal Wetland Protection Act of 1989, State of 

Maryland, and were adopted in 1991. 

Additional Initiatives

The Committee is currently prioritizing properties for acquisition and looking for sources of funding. The State and 

county purchased 400 acres of Mountain Road property in 

2002 for the Magothy River Greenway hub. This acquisition 

preserves two of the peatlands, South Gray’s and Blackhole 

Creek bogs. Also, the State of Maryland has purchased 

two lots that were to be developed with single family homes 

in the Maryland Avenue bog complex. The purchases not 

only help preserve the bogs but also their essential ground 

water recharge areas. Landowners have protected additional 

building lots platted within the bogs for use as forest preservation credit within the Chesapeake Bay Critical Area.

The Committee has undertaken the restoration of a 3-acre 

sea level fen that had been buried under material dredged for 

a nearby community marina in the 1970s. The restoration

area is located directly downstream of the North Grays Creek

bog complex. The dredged material and its common reed 

[Phragmites australis (Cav.) Trin.] mat will be removed and 

replaced with clean Magothy formation sands dredged from 

North Gray’s Creek tidal channels. In addition, the Anne 

Arundel County Department of Public Works has undertaken

restoration and/or enhancement projects at several other peatlands including stormwater retrofits, fill removal, nonpoint 

source water quality improvements, and restoration of hydrology. When appropriate, AWC seedlings from local provenances will be planted in restoration and enhancement projects

to augment existing populations.

The Maryland Department of the Environment is currently 

in the process of revising its nontidal wetland regulations to 

include other Anne Arundel County peatlands that are not 

listed in regulation as NTWSSC. This will extend the added 

State regulatory protections and a 100-foot buffer to all of 

the known bogs, peatlands and AWC forests located in Anne 

Arundel County.

CONCLUSION

As a result of the intensive efforts of the Committee, new 

State and County regulations have been developed and 

implemented for protecting the peatlands of Anne Arundel 

County. Known peatlands have been delineated, named, 

and mapped. The regulatory buffers have been expanded 

to protect sensitive areas including upslope drainage and 

groundwater recharge areas. However, these regulations 

are not a panacea and do not prohibit all development in the 

watersheds feeding the peat bogs. In fact, some property 

owners have lobbied for a relaxation of the protection mechanisms. The committee is concerned that additional peatland 

discoveries in Anne Arundel County may be difficult, if not 

impossible, to add to the county protection program. As 

population growth pressures continue to escalate in the 

Chesapeake Bay watershed, more applications for permits 

to disturb sensitive areas are anticipated by the regulatory 

agencies. Several properties containing peatlands are for 

sale at exorbitant waterfront prices which governmental 

agencies cannot afford to purchase and preserve. However, 

the Committee is dedicated to continuing its work to protect 

these valuable wetland resources.

ACKNOWLEDGMENTS

Special thanks to the Committee, particularly Keith Underwood

and State delegate Joan Cadden, the catalysts for protecting 

the “bogs” and also to David Walbeck for editing assistance. 

LITERATURE CITED

County Council of Anne Arundel County, Maryland. 2002. An 

ordinance concerning: bog protection program. Bill No. 105–01. 

Annapolis, MD. 24 p.

Code of Maryland Regulations. 2001. Title 26, Department of 

the Environment, Subtitle 23, Nontidal wetlands. Office of the 

Secretary of State, Division of State Documents, Annapolis, MD. 

Kirby, R.M.; Matthews, E.D. 1973. Soil survey of Anne Arundel 

County, Maryland. Washington, DC: U.S. Department of 

Agriculture. U.S. Government Printing Office. 127 p.

Sipple, W.S. 1999. Days afield: exploring wetlands in the Chesapeake

Bay region. Baltimore, MD: Gateway Press. 558 p.

Vokes, H.E. 1957. Geography and geology of Maryland. Maryland 

Geological Survey, Bulletin 19, Baltimore, MD. 243 p.

Table 1—Hierarchical decision tree for regulating State 

nontidal wetlands in Anne Arundel County, Maryland

1a. The nontidal wetland impacts are minor

 (< 5,000 square feet with no significant

 plant or wildlife value . . . . . . . . . . . . . . . . . . . . . . . . . . 2

 2a. The impacts are determined to be minimally 

 adverse — activity exempt

 2b. The impacts to nontidal wetlands are 

 < 5,000 square feet — 25-foot regulated buffer

 and an expedited review w/o public notice

1b. The nontidal wetland impacts are major

 (> 5,000 square feet or with significant plant or 

 wildlife value) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

 3a. Full permit review with public notice —

 25-foot regulated buffer

 3b. Nontidal Wetlands of Special State Concern 

 listed in regulation — 100-foot regulated buffer
65

INTRODUCTION

The decline of Atlantic white-cedar [Chamaecyparis thyoides 

(L.) B.S.P.], abbreviated AWC, during the last few centuries is 

supported by scientific and historical accounts (Cottrell 1929, 

Vermeule and Pinchot 1900). With the acknowledged value 

of wetlands, it has become increasingly important to maintain 

and restore wetland communities whenever possible. Many 

studies focus only on the first few years following restoration. 

Therefore, long-term data, especially as they relate to the 

effect of various treatments, are needed. This study examines vegetational changes over a 10-year period at an AWC 

regeneration site in southern New Jersey, and examines the 

long-term effects of slash and deer protection treatments on 

AWC regeneration. 

In 1990, seven AWC restoration and regeneration study sites 

were established from the Jackson State Forestry Resource 

Education Center south to Belleplain State Forest in New 

Jersey. Several different cedar loss scenarios were studied, 

and the major factors thought to be limiting cedar regeneration were experimentally manipulated. These limiting factors 

included deer browsing, hardwood competition, logging slash

(plant materials left after logging) and availability and type of

cedar propagules. Penn Swamp, located in Wharton State 

Forest, was one of these study sites: a clearcut cedar harvest

that focused on deer and logging slash effects. Following 

yearly measurements between 1990 and 1995, four of the 

seven sites, including Penn Swamp, were designated as 

long-term sites to be remeasured periodically until 2010. 

All vegetation would be remeasured on permanent plots to 

characterize long term community dynamics.

METHODS

Site

Penn Swamp is a 55-ha AWC stand located in Wharton State

Forest in the southern New Jersey Pine Barrens. Delays from

spiking AWC trees by unknown environmentalists caused the

clearcutting of 3.4-ha to extend from late 1989 to early 1991. 

This did not affect the areas where the data were collected 

which all “started” at the same time. A pre-clearcut survey 

was done in 1989 on 34 randomly selected plots. The point 

sampling technique, which employs an angle gauge or prism

was used to sample canopy trees, since this method tallies 

trees based on their sizes rather than their frequencies (Avery

and Burkhart 1994). Table 1 gives a summary of the point 

sampled canopy composition. AWC dominated the overstory

of the pre-cut forest in average diameter, frequency, and 

number of stems. The pre-cut understory included Vaccinium 

corymbosum L., Rhododendron viscosum (L.) Torr., Leucothoe

racemosa (L.) Gray, Gaylussaccia frondosa (L.) T.&G., Acer

rubrum L., Nyssa sylvatica Marshall, and AWC (Zimmermann 

1992). 

Zimmermann and others (1999) found the soils to be Typic 

histosols, varying from zero thickness near the edges of the 

swamp to 193 cm deep near an old stream channel that ran 

through the swamp. The peat at 186 cm was radiocarbon 

dated to 9980 ± 240 YBP. Charcoal, evidence of fire, was 

found throughout the extracted peat cores. Aerial photographs

of Penn Swamp taken in 1940, 1962, 1974, and 1986 showed

a dynamic ecosystem with different scales and levels of 

disturbance producing a multi-age AWC stand (Zimmermann 

and others 1999).

ATLANTIC WHITE-CEDAR REGENERATION AND VEGETATION DYNAMICS

AT PENN SWAMP, NEW JERSEY: TEN YEARS OF CHANGE

George L. Zimmermann and Kristin A. Mylecraine1

1 George L. Zimmermann, Professor of Environmental Studies, Richard Stockton College of New Jersey, Division of Natural Sciences and 

Mathematics, Pomona, NJ 08240–0195; and Kristin A. Mylecraine, Postdoctoral Researcher, Ohio State University, Department of Evolution, 

Ecology and Organismal Biology, Columbus, OH 43210.

Citation for proceedings: Burke, Marianne, K.; Sheridan, Philip, eds. 2005. Atlantic white cedar: ecology, restoration, and management: 

Proceedings of the Arlington Echo symposium. Gen. Tech. Rep. SRS-91. Asheville, NC: U.S. Department of Agriculture, Forest Service, 

Southern Research Station. 74 p.

Abstract—Penn Swamp is a 55-ha Atlantic white-cedar [Chamaecyparis thyoides (L.) B.S.P.] stand in southern New Jersey. 

In 1989–1990, a 3.4 ha area was clearcut and a woven fence (> 3 m tall) was erected around 3-ha, leaving 0.4 ha unprotected from deer. Within both protected and unprotected areas, three logging slash treatments were delineated: no slash, 

slash, and double slash in a Latin square design. Permanent plots were established to monitor white-cedar regeneration 

and long-term vegetation dynamics. All vegetation was identified and measured by height class (< 0.3 m, 0.3 to < 0.6 m, 0.6 

to < 1.3 m, and ≥ 1.3 m), annually between 1990 and 1995, and again in 2000. The effect of slash on cedar was statistically though probably not biologically significant in one instance (cedar over 1.3 m inside the fence). Deer impact remains 

dramatic, and manifested by inadequate cedar stocking, over dominance of shrubs, and few cedar reaching the 0.3 to 0.6 m 

height class in unprotected areas.

Keywords: Atlantic white-cedar, browse, deer, long-term effects, vegetation impacts.
66

Experimental Design

A 3.05 m high woven deer fence was erected, encompassing 

3.0 of the 3.4-ha clearcut area. The fenced portion of the site 

served as the treatment (deer exclusion) and the unfenced 

area (0.4 ha) served as the control. Within each of these 

protection levels (fenced and unfenced), two Latin squares 

were established to partition potential confounding variation 

in the x and y dimensions (fig. 1). In this case, the partitioned 

variations that were considered potential problems were: 

moisture gradients and residual stand effects. The Latin 

squares contained three slash treatments: no slash (N), 

normal slash (S), and double slash (D). Logging slash was 

composed of cedar branches and undesirable cut trees such 

as swamp hardwoods left on the site after logging. The slash 

treatments were established shortly after most of the stand 

was clearcut (November 1990). Due to delays by the State 

contractor, the deer fence was not erected until after the 

first winter had passed (May 1991). The fence has not been 

maintained since 2001, and gaps now exist in some places 

along its perimeter.

Vegetation Surveys

Data were collected on the site before and after the clearcut. 

Full surveys (n = 72) were conducted in 1989, 1991, 1992, 

1993, 1994, 1995, and 2000. The full surveys included (1) 

a point sample of canopy trees, (2) a five square m plot to 

record vegetation by height classes 0.3 to < 0.6 meters, 0.6 

to < 1.3 meters and ≥ 1.3 meters tall, (3) a 1 square m plot to 

record vegetation < 0.3 meters tall and to establish percent 

ground cover, and (4) a 2.5-m transect to record interception

lengths of downed debris. The point sample has not been 

used since the mature trees were cut in 1989–90, and the

debris transect was not conducted in the 2000 survey since

no more information was needed on conditions for seed 

germination and establishment. Detailed plot instructions 

and a sample plot card can be found in earlier reports 

(Zimmermann 1992, 1993, 1995).

Data Analysis

The vegetation data generated consisted of density (number 

per hectare), percent browsed (number of total stems showing 15 percent or more of their branches clipped), and percent frequency (the percentage of total plots on which the 

species is present). The data here were analyzed by treatment, species and height classes. Density and percent 

browse (not presented here due to space limitations) were 

modeled to test the effects of the deer and slash treatments.

Models were run by species and height classes. The statistical analyses for all sites followed the same procedure: analysis of variance (ANOVA) were run using PROC General 

Linear Models (GLM ) on SAS (SAS Institute 2003). If data

met ANOVA assumptions and statistically significant models 

were found, two multiple comparison tests (Tukey and RyanEinot-Gabriel-Welsch) were performed to determine treatment

differences—if there was a rare disagreement among the 

two tests, Tukey was preferred. If data did not meet ANOVA 

assumptions, even after transformations, then nonparametric 

SAS procedures (NPAR1WAY) were performed.

Table 1—Pre-clearcut point sample of Penn Swamp canopy done in 1989 (n=34)

 Standard 

Species Mean density error Mean DBH Frequency

No./ha cm percent

246.3 68.9 20.1 44.1

Betula populifolia 15.7 15.7 11.6 2.9

Chamaecyparis thyoides 1189.9 123.6 25.0 97.0

Magnolia virginiana 324.7 208.1 7.6 11.7

Nyssa sylvatica 22.8 20.4 22.4 5.8

Figure 1—Close-up diagram of the experimental setup at Penn Swamp: deer exclosure and 

logging slash treatments.
67

Table 2—Vegetation at Penn Swamp in the year 2000 by treatment. mdens = are mean densities per hectare, sen = the standard error of the mean for mean density, mper = mean percent of stems browsed, sfreq = the percent of plots a species was found on. 3 = the < .3 m height class, 36 = the .3 to < .6 m height class, 63 = the .6 to < 1.3 m height class, 13 = > 1.3 m height class. The sample size per treatment was 12, a total of 72 sample points. Statistical significance 

(prob < .05) for protection from deer is indicated for density and percent browse data by a superscript of “*”. Slash was only significant for white cedar density 

in the > 1.3 m height category.Species mdens3 sen3 mper3 sfreq3 mdens36 sen36 mper36 sfreq36 mdens63 sen63 mper63 sfreq63 mdens13 sen13 sfreq13

Fence—No Slash 

Acer rubrum 5000.0* 2302.8 0.0 33.3 0.0 0.0 0.0 0.0 666.7* 284.3 0.0 33.3 2166.7* 796.1 50.0

Chamaecyparis thyoides 74166.7 17772.1 20.8* 91.7 6666.7* 1620.6 26.8* 83.3 6666.7* 2035.0 10.0 58.3 46500.0* 7683.6 100.0Clethra alnifolia 27500.0 12560.5 0.0 50.0 333.3* 224.7 0.0 16.7 666.7* 376.1 0.0 25.0 333.3* 224.7 16.7FERNS 20000.0 10000.0 0.0 16.7 . . . . . . . . . . . Gaylussacia frondosa 0.0 0.0 . 0.0 166.7 166.7 0.0 8.3 333.3* 224.7 0.0 16.7 2166.7* 1641.5 33.3Kalmia angustifolia 3333.3* 3333.3 0.0 8.3 0.0* 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0

Leucothoe racemosa 2500.0 1305.6 0.0 25.0 333.3 224.7 0.0 16.7 1333.3* 710.7 0.0 33.3 6000.0 3256.7 41.7

Lyonia ligustina 0.0 0.0 . 0.0 166.7* 166.7 0.0 8.3 166.7 166.7 0.0 8.3 666.7* 666.7 8.3

Magnolia virginiana 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 . 0.0 166.7 166.7 8.3Nyssa sylvatica 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 . 0.0 666.7 512.5 16.7Rhexia virginica 2500.0 2500.0 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0Rhododendron viscosum 27500.0 10597.7 0.0 50.0 1500.0* 857.2 0.0 33.3 2166.7* 625.6 0.0 66.7 8000.0* 2215.6 75.0

Rubus hispidus 19166.7 17427.7 0.0 16.7 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0Sedge or Carex spp 84166.7 23043.4 20.0 83.3 333.3* 333.3 0.0 8.3 666.7 666.7 0.0 8.3 0.0 0.0 0.0

Smilax spp. 1666.7 1666.7 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 166.7* 166.7 8.3

Toxicodendron radicans 10000.0 4438.1 0.0 33.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0Vaccinium corymbosum 50833.3 12089.2 0.0 100.0 4000.0* 1128.2 0.0 83.3 11833.3 2194.5 0.0 91.7 22833.3* 2865.2 100.0Vaccinium vacillans 23333.3 11827.9 0.0 33.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0

Fence—Slash 

Acer rubrum 2500.0* 1305.6 0.0 25.0 333.3 333.3 0.0 8.3 500.0* 261.1 0.0 25.0 1500.0* 609.3 41.7Chamaecyparis thyoides 35000.0 8211.2 29.9* 83.3 5000.0* 1141.5 31.1* 75.0 6000.0* 2229.3 0.0 66.7 33500.0* 6015.8 100.0Clethra alnifolia 17500.0 5919.3 20.0 50.0 1500.0* 1018.8 0.0 25.0 2333.3* 1150.3 0.0 33.3 2666.7* 1214.4 41.7FERNS 20000.0 10000.0 0.0 16.7 . . . . . . . . . . . Gaylussacia frondosa 0.0 0.0 . 0.0 0.0* 0.0 0.0 0.0 333.3* 224.7 0.0 16.7 1666.7* 948.2 25.0Leucothoe racemosa 2500.0 2500.0 0.0 8.3 500.0 358.9 0.0 16.7 1333.3* 864.6 0.0 25.0 11500.0 4697.7 66.7

Lyonia ligustina 0.0 0.0 . 0.0 0.0* 0.0 0.0 0.0 166.7 166.7 0.0 8.3 166.7* 166.7 8.3

Nyssa sylvatica 0.0 0.0 . 0.0 0.0 0.0 0.0 0.0 166.7 166.7 0.0 8.3 666.7 376.1 25.0Pinus rigida 833.3 833.3 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0

Rhododendron viscosum 10833.3 4993.7 0.0 41.7 1000.0* 522.2 0.0 33.3 2333.3* 594.6 0.0 66.7 6000.0* 1633.0 66.7

Rubus hispidus 5000.0 5000.0 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0Sedge or Carex spp 89166.7 34519.6 0.0 83.3 0.0* 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0

Smilax spp. 833.3 833.3 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0* 0.0 0.0

Toxicodendron radicans 16666.7 10323.1 0.0 33.3 0.0 0.0 0.0 0.0 500.0 500.0 0.0 8.3 166.7 166.7 8.3Vaccinium corymbosum 37500.0 8971.8 0.0 100.0 5000.0* 1446.0 0.0 75.0 10500.0 2271.4 0.0 91.7 20000.0* 3266.0 100.0Vaccinium vacillans 2500.0 1794.4 0.0 16.7 166.7 166.7 0.0 8.3 166.7 166.7 0.0 8.3 0.0 0.0 0.0

(continued)
68Table 2—Vegetation at Penn Swamp in the year 2000 by treatment. mdens = are mean densities per hectare, sen = the standard error of the mean for mean 

density, mper = mean percent of stems browsed, sfreq = the percent of plots a species was found on. 3 = the < .3 m height class, 36 = the .3 to < .6 m height class, 63 = the .6 to < 1.3 m height class, 13 = > 1.3 m height class. The sample size per treatment was 12, a total of 72 sample points. Statistical significance 

(prob < .05) for protection from deer is indicated for density and percent browse data by a superscript of “*”. Slash was only significant for white cedar density 

in the > 1.3 m height category. (continued)Species mdens3 sen3 mper3 sfreq3 mdens36 sen36 mper36 sfreq36 mdens63 sen63 mper63 sfreq63 mdens13 sen13 sfreq13

Fence—Double Slash

Acer rubrum 4166.7* 3361.6 0.0 16.7 0.0 0.0 0.0 0.0 166.7* 166.7 0.0 8.3 4833.3* 3415.3 50.0

Aronia spp. 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 . 0.0 166.7 166.7 8.3Chamaecyparis thyoides 28333.3 9987.4 11.2* 58.3 2500.0* 783.3 12.5* 58.3 4833.3* 1266.3 20.0 83.3 24000.0* 4052.7 100.0Clethra alnifolia 20000.0 12851.1 0.0 33.3 2500.0* 1234.0 0.0 41.7 2000.0* 984.7 0.0 41.7 2500.0* 2147.9 25.0Fern spp. 140000.0 . 0.0 8.3 . . . . . . . . . . . Gaylussacia frondosa 833.3 833.3 0.0 8.3 0.0* 0.0 0.0 0.0 666.7* 512.5 0.0 16.7 2500.0* 1578.7 25.0Leucothoe racemosa 1666.7 1123.7 0.0 16.7 333.3 224.7 0.0 16.7 333.3* 333.3 0.0 8.3 4166.7 2194.5 41.7

Pinus rigida 833.3 833.3 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0

Rhododendron viscosum 15833.3 4839.6 0.0 66.7 3000.0* 937.4 0.0 58.3 4333.3* 1226.8 0.0 75.0 10833.3* 3554.4 100.0

Rubus hispidus 833.3 833.3 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0Sedge or Carex spp 64166.7 16070.8 0.0 75.0 0.0* 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0

Smilax spp. 5000.0 5000.0 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 500.0* 261.1 25.0

Toxicodendron radicans 4166.7 3361.6 0.0 16.7 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0Vaccinium corymbosum 41666.7 10998.2 0.0 75.0 4833.3* 1526.7 0.0 66.7 9333.3 1263.3 0.0 100.0 28000.0* 5087.1 100.0Vaccinium vacillans 2500.0 2500.0 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0

No Fence—No Slash 

Acer rubrum 23333.3* 8378.7 0.0 75.0 0.0 0.0 . 0.0 0.0* 0.0 . 0.0 166.7* 166.7 8.3Betula populifolia 0.0 0.0 . 0.0 0.0 0.0 0.0 0.0 166.7 166.7 0.0 8.3 166.7 166.7 8.3Chamaecyparis thyoides 12500.0 3508.6 96.9* 66.7 0.0* 0.0 0.0* 0.0 0.0* 0.0 . 0.0 0.0* 0.0 0.0Clethra alnifolia 0.0 0.0 . 0.0 166.7* 166.7 0.0 8.3 0.0* 0.0 0.0 0.0 0.0* 0.0 0.0Gaylussacia frondosa 0.0 0.0 . 0.0 1333.3* 666.7 0.0 33.3 5666.7* 2384.7 0.0 50.0 8500.0* 2641.5 66.7Grass spp. 0.0 0.0 . 0.0 3333.3* 3333.3 0.0 8.3 2500.0* 1725.5 0.0 16.7 0.0 0.0 0.0

Ilex verticillata 10000.0 10000.0 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0Kalmia angustifolia 17500.0* 12500.0 0.0 33.3 1166.7* 833.3 0.0 25.0 333.3 224.7 0.0 16.7 0.0 0.0 0.0

Leucothoe racemosa 2500.0 1305.6 0.0 25.0 2833.3 1242.1 0.0 50.0 7333.3* 2260.8 0.0 66.7 11166.7 3613.6 75.0

Lyonia ligustina 10000.0 4438.1 0.0 50.0 2666.7* 1639.2 0.0 41.7 500.0 358.9 0.0 16.7 1333.3* 864.6 25.0

Mitchella repens 14166.7* 9728.0 0.0 16.7 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0

Nyssa sylvatica 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 . 0.0 333.3* 333.3 8.3

Pinus rigida 0.0 0.0 . 0.0 333.3 333.3 100.0 8.3 0.0 0.0 0.0 0.0 333.3 333.3 8.3

Rhododendron viscosum 25000.0 8393.7 0.0 75.0 166.7* 166.7 0.0 8.3 333.3* 224.7 0.0 16.7 333.3 224.7 16.7Rhus copallina 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 . 0.0 166.7 166.7 8.3Rubus hispidus 28333.3 16914.8 0.0 25.0 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0Sedge or Carex spp 22500.0 13434.7 0.0 25.0 666.7* 449.5 0.0 16.7 0.0 0.0 0.0 0.0 0.0 0.0 0.0

Smilax spp. 2500.0 1305.6 0.0 25.0 666.7 512.5 0.0 16.7 500.0 500.0 0.0 8.3 4500.0* 2536.1 33.3

Toxicodendron radicans 2500.0 2500.0 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0Vaccinium corymbosum 25833.3 7732.1 0.0 75.0 2833.3* 1057.7 0.0 58.3 10166.7 1833.3 0.0 100.0 34666.7* 5664.0 100.0Vaccinium vacillans 2500.0 2500.0 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0

(continued)
69

Table 2—Vegetation at Penn Swamp in the year 2000 by treatment. mdens = are mean densities per hectare, sen = the standard error of the mean for mean density, mper = mean percent of stems browsed, sfreq = the percent of plots a species was found on. 3 = the < .3 m height class, 36 = the .3 to < .6 m height class, 63 = the .6 to < 1.3 m height class, 13 = > 1.3 m height class. The sample size per treatment was 12, a total of 72 sample points. Statistical significance 

(prob < .05) for protection from deer is indicated for density and percent browse data by a superscript of “*”. Slash was only significant for white cedar density 

in the > 1.3 m height category. (continued)Species mdens3 sen3 mper3 sfreq3 mdens36 sen36 mper36 sfreq36 mdens63 sen63 mper63 sfreq63 mdens13 sen13 sfreq13

No Fence—Slash 

Acer rubrum 42500.0* 24187.6 0.0 66.7 166.7 166.7 0.0 8.3 500.0* 500.0 0.0 8.3 0.0* 0.0 0.0

Aronia spp. 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 . 0.0 166.7 166.7 8.3Betula populifolia 0.0 0.0 . 0.0 166.7 166.7 0.0 8.3 0.0 0.0 0.0 0.0 166.7 166.7 8.3Chamaecyparis thyoides 19166.7 5288.4 72.2* 75.0 0.0* 0.0 0.0* 0.0 0.0* 0.0 . 0.0 166.7* 166.7 8.3

Chamaedaphne calyculata 8333.3 8333.3 0.0 8.3 1500.0 1500.0 0.0 8.3 333.3 333.3 0.0 8.3 0.0 0.0 0.0Clethra alnifolia 1666.7 1666.7 0.0 8.3 0.0* 0.0 . 0.0 0.0* 0.0 . 0.0 0.0* 0.0 0.0

FERNS 25000.0 5000.0 0.0 16.7 8000.0 0.0 0.0 16.7 0.0 0.0 0.0 0.0 . . . Gaylussacia frondosa 2500.0 1305.6 0.0 25.0 333.3* 224.7 0.0 16.7 2333.3* 846.9 0.0 50.0 12166.7* 4549.1 75.0Grass spp. 0.0 0.0 . 0.0 500.0* 500.0 0.0 8.3 0.0* 0.0 0.0 0.0 0.0 0.0 0.0

Ilex verticillata 39166.7 39166.7 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0Kalmia angustifolia 3333.3* 3333.3 0.0 8.3 500.0* 358.9 0.0 16.7 500.0 500.0 0.0 8.3 0.0 0.0 0.0

Leucothoe racemosa 1666.7 1123.7 0.0 16.7 666.7 376.1 0.0 25.0 3833.3* 716.0 0.0 83.3 7500.0 3403.4 58.3

Lyonia ligustina 5000.0 2302.8 0.0 33.3 166.7* 166.7 0.0 8.3 500.0 358.9 0.0 16.7 666.7* 512.5 16.7

Mitchella repens 54166.7* 54166.7 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0

Nyssa sylvatica 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 . 0.0 500.0 261.1 25.0Pinus rigida 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 . 0.0 166.7 166.7 8.3

Rhododendron viscosum 5833.3 3128.2 0.0 25.0 166.7* 166.7 0.0 8.3 0.0* 0.0 0.0 0.0 166.7* 166.7 8.3

Rubus hispidus 46666.7 18020.8 0.0 50.0 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0Sedge or Carex spp 39166.7 12459.5 0.0 58.3 4833.3* 2599.0 0.0 25.0 0.0 0.0 0.0 0.0 1666.7 1666.7 8.3

Smilax spp. 4166.7 4166.7 0.0 8.3 166.7 166.7 0.0 8.3 0.0 0.0 0.0 0.0 1500.0* 821.1 25.0

Toxicodendron radicans 1666.7 1666.7 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0Vaccinium corymbosum 29166.7 7120.0 0.0 75.0 2166.7* 716.0 0.0 58.3 14166.7 3785.6 0.0 91.7 46000.0* 6372.3 91.7Vaccinium vacillans 6666.7 3097.7 0.0 33.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0

No Fence—Double Slash 

Acer rubrum 36666.7* 25055.5 0.0 75.0 166.7 166.7 0.0 8.3 0.0* 0.0 0.0 0.0 166.7* 166.7 8.3Chamaecyparis thyoides 20000.0 6396.0 93.3* 66.7 1000.0* 674.2 50.0* 16.7 166.7* 166.7 0.0 8.3 166.7* 166.7 8.3

Chamaedaphne calyculata 12500.0 12500.0 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0Clethra alnifolia 2500.0 1794.4 0.0 16.7 166.7* 166.7 0.0 8.3 166.7* 166.7 0.0 8.3 0.0* 0.0 0.0

FERNS 30000.0 . 0.0 8.3 5000.0 1000.0 0.0 16.7 0.0 0.0 0.0 0.0 . . . Gaylussacia frondosa 2500.0 1305.6 0.0 25.0 1000.0* 522.2 0.0 33.3 2333.3* 731.7 0.0 58.3 9833.3* 2467.5 83.3Grass spp. 0.0 0.0 . 0.0 4000.0* 2984.8 0.0 25.0 2500.0* 1635.3 0.0 25.0 0.0 0.0 0.0

Ilex glabra 833.3 833.3 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0Ilex verticillata 3333.3 3333.3 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0Kalmia angustifolia 10000.0* 8348.5 0.0 16.7 1500.0* 1183.9 0.0 16.7 1000.0 1000.0 0.0 8.3 0.0 0.0 0.0

Leucothoe racemosa 2500.0 2500.0 0.0 8.3 333.3 333.3 0.0 8.3 3166.7* 903.1 0.0 66.7 15000.0 5357.0 75.0

Lyonia ligustina 4166.7 2599.0 0.0 25.0 666.7* 666.7 0.0 8.3 333.3 224.7 0.0 16.7 1333.3* 791.4 25.0

(continued)
70Table 2—Vegetation at Penn Swamp in the year 2000 by treatment. mdens = are mean densities per hectare, sen = the standard error of the mean for mean 

density, mper = mean percent of stems browsed, sfreq = the percent of plots a species was found on. 3 = the < .3 m height class, 36 = the .3 to < .6 m height class, 63 = the .6 to < 1.3 m height class, 13 = > 1.3 m height class. The sample size per treatment was 12, a total of 72 sample points. Statistical significance 

(prob < .05) for protection from deer is indicated for density and percent browse data by a superscript of “*”. Slash was only significant for white cedar density 

in the > 1.3 m height category. (continued)Species mdens3 sen3 mper3 sfreq3 mdens36 sen36 mper36 sfreq36 mdens63 sen63 mper63 sfreq63 mdens13 sen13 sfreq13Magnolia virginiana 833.3 833.3 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0Mitchella repens 11666.7* 11666.7 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0

Nyssa sylvatica 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 . 0.0 166.7 166.7 8.3Pinus rigida 2500.0 1305.6 0.0 25.0 0.0 0.0 0.0 0.0 166.7 166.7 0.0 8.3 166.7 166.7 8.3

Rhododendron viscosum 13333.3 10894.4 0.0 16.7 333.3* 224.7 0.0 16.7 666.7* 449.5 0.0 16.7 500.0* 358.9 16.7

Sedge or Carex spp 44166.7 20205.7 0.0 41.7 9500.0* 6652.1 0.0 33.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0

Smilax spp. 6666.7 6666.7 0.0 8.3 0.0 0.0 0.0 0.0 166.7 166.7 0.0 8.3 1666.7* 1344.6 16.7

Vaccinium corymbosum 24166.7 7432.4 0.0 66.7 1666.7* 689.0 0.0 41.7 13333.3 2538.6 0.0 83.3 31666.7* 6256.3 100.0Vaccinium vacillans 833.3 833.3 0.0 8.3 0.0 0.0 . 0.0 0.0 0.0 . 0.0 0.0 0.0 0.0

RESULTS AND DISCUSSION

The first 5 years of measurements showed the severe impact 

of white tail deer on AWC regeneration (Zimmermann 1992, 

1993, 1995, 1997). This effect is still obvious 10 years later 

(year 2000). Table 2 shows year 2000 vegetation density

and frequency by treatment combinations. AWC generally 

are denser and more frequent inside the fence than outside. 

In 2000, protection from deer was not statistically significant 

for cedar under 0.3 m but was significant in all larger height 

classes. For AWC ≥ 1.3 m, there was also a statistically 

significant interaction between protection from deer and 

slash treatment (p < .017). Deer protection was also signifi-

cant for a number of other species: statistically significant 

differences for density were found for Acer rubrum, Clethra 

alnifolia L., Gaylussacia frondosa, Lyonia lingustrina (L.) 

DC, Rhododendron viscosum, and Vaccinium corybosum. 

Figure 2 shows the treatment effects in 2000 by vegetation 

classes. Deer impact on cedar and the shrub community is 

profound. In 2001, Dr. Gerry Moore, Director, the Department 

of Science at the Brooklyn Botanical garden in New York 

conducted three surveys (spring, summer, and fall) of 

the Penn Swamp study area to document any other plant 

species not found by the permanent plots. Table 3 presents 

those species by protection treatment, not already listed in 

Table 2 and/or those found in the 2001 survey. Species diver

-

sity was richer outside the fence where there was inadequate 

cedar regeneration. The dense, uniform, and closed cedar 

canopy inside the fence probably created less environmental 

heterogeneity and opportunities for other plant species.

In the first 5 years of the study, slash appeared to only affect 

cedar in the lowest height class with little impact in the higher 

height classes (Zimmermann 1992, 1993, 1995, 1997). In 

2000, the only statistically significant impact on vegetation 

from slash occurred on the > 1.3 m AWC inside the fence. 

However, the difference between the highest AWC density 

inside the fence, 46,500 cedar/ha (> 1.3 m), found in the no 

slash treatment, is probably not biologically different from the 

lowest density (24,000/ha in double slash, inside the fence 

treatment for > 1.3 m stems). There will probably be more 

than adequate AWC even at the double slash levels (inside 

the fence) to bring the stand to a ‘normal’ stocking level. The 

reduced impact of slash found in 2000 could be due to the 

low inherent biological impact of slash at the levels studied 

here, but could also be due to the degradation of the slash, 

whose layering has decreased as well as decomposing 

over 10 years. Korstian and Bush (1931) and Little (1950) 

maintain that slash has a negative impact on AWC regen

-

eration, while Cottrell (1929) thought differently. It is easy 

to see how our results could support either view: double 

slash did reduce cedar density but the densities are still high 

enough to maintain “normal” or fully stocked levels provided 

the cedar remain dominant. Because logging slash can vary 

from site to site, more studies are needed to examine these 

issues in depth. 
71

Figure 2—The overall effect of treatments on vegetation by category (all height classes combined) in the year 2000 

at Penn Swamp. AWC = Atlantic white-cedar, other trees = all other tree species combined, shrubs = all multistemmed woody plants combined, and plants = all herbaceous and vine-like plants combined.

Table 3—Species listed are those not already found in table 2 (because 

their densities were not statistically significant between fenced and 

unfenced), and/or species found in spring, summer, and fall 2001 floral 

surveys conducted in Penn swamp treatments

Inside the deer fence Outside the deer fence

Juncus effusus (L.) Andropogon glomeratus (Walt.) B.S.P.

Woodwardia virginica (L.) Sm Andropogon virginicus (L.)

Carex atlantica (Bailey)

 Carex striata var. brevis (Bailey)

Drosera intermedia (Hayne)

Drosera rotundifolia (L.)

Dulichium arundinaceum (L.) Britt.

Juncus effusus (L.)

Magnolia virginiana (L.)

Muhlenbergia uniflora (Muhl.) Fern 

Thelypteris simulata (Davenport) Nieuwl.

Triadenum virginicum (L.) Raf.

Woodwardia areolata (L.) T. Moore

Woodwardia virginica (L.) Sm.

Xyris difformis Chapman
72

CONCLUSION

Various auto and allogenic forces over centuries have 

created a complex, multi-aged forest at Penn Swamp. This 

heterogeniety demands a management plan that takes 

this variability into consideration. Regeneration over the 

last 10 years has been heavily impacted by white tail deer. 

These effects are profound and mirror similar past findings 

in New Jersey (Little and others 1958). The slash load at 

Penn Swamp, while negatively affecting AWC regeneration 

in only the double slash treatment, will still probably allow a 

‘full’ or normal stocking of AWC to occur, provided they are 

protected from deer. Like all natural systems, many forces 

are at play at Penn Swamp; that is why this and similar vegetation studies will be continued for 10 more years. More longterm data are needed from many more sites so management 

decisions can be adequately assessed.

ACKNOWLEDGMENTS

Funding for this project was provided by the New Jersey 

Department of Environmental Protection’s Office of Science 

and Research, the New Jersey Forest Service, the USDA 

Forest Service, and Richard Stockton College of New 

Jersey. Many thanks to the administration, faculty, staff, and 

students of Richard Stockton College of New Jersey and the 

personnel of the NewJersey Forest Service. Special thanks 

to George Pierson, Martin Rosen, K.O. Summerville, Robert 

Williams, Gerry Moore, Richard Trout, John Kuser, Les 

Alpaugh, and Thomas Keck.

LITERATURE CITED

Avery, T.E.; Burkhart, H.E. 1994. Forest Measurements. New York: 

McGraw-Hill. 408 p. 

Cottrell, A.T. 1929. Some preliminary observations on the management and utilization of southern white cedar in the coastal plain of 

New Jersey. New Haven, CT: Yale University. 37 p. MS Thesis.

Korstian, C.F.; Brush, W.D. 1931. Southern white cedar. Tech. Bull. 251.

U.S. Department of Agriculture. 75 p.

Little, S. 1950. Ecology and silviculture of white cedar and associated

hardwoods in southern New Jersey. Sch. For. Bull. 56. Yale University. 103 p.

Little, S.; Allen, J.P.; Somes, H.A. 1958. Forestry and deer in the 

Pine region of New Jersey. Res. Pap. NE–109. U.S. Department of 

Agriculture Forest Service. 33 p.

Mylecraine, K.A.; Zimmermann, G.L. 2000. Atlantic white-cedar 

ecology and best management practices manual. New Jersey 

Department of Environment. Protection. 84 p.

SAS Institute Inc. 2003. SAS/STAT user’s guide. Cary, N.C: SAS 

Institute Inc.

Vermeule, C.C.; Pinchot, G. 1900. The forests of New Jersey. In: Ann. 

Rep. of New Jersey State Geologist for 1899. Trenton, NJ: 13-101, 

137-172.

Zimmermann, G.L. 1992. Investigation of techniques to regenerate 

Atlantic white-cedar (Chamaecyparis thyoides). Final report. 175 p. 

Submitted to: New Jersey Department of Environment Protection. 

Division of Science and Research. NAMS, Richard Stockton 

College, Pomona, NJ. 

Zimmermann, G.L. 1993. Continuation of the Atlantic white-cedar 

regeneration experiments. Final report. 190 p. Submitted to: 

New Jersey Department of Environment Protection and U.S. 

Forest Service. Richard Stockton College, Department of Natural 

Sciences and Mathematics, Pomona, NJ.

Zimmermann, G.L. 1995. The Atlantic white-cedar regeneration 

experiments. Years 3 and 4 final reports. 225 p. Submitted to: 

New Jersey Department of Environment Protection and U.S. 

Forest Service. Richard Stockton College, Department of Natural 

Sciences and Mathematics, Pomona, NJ.

Zimmermann G. 1997. The Atlantic white-cedar (Chamaecyparis 

thyoides) regeneration experiments. Final Report. 157 p. Submitted

to: New Jersey Department of Environment Protection and U.S. 

Forest Service. Richard Stockton College, Department of Natural 

Sciences and Mathematics, Pomona, NJ.

Zimmermann, G.L.; Mueller, R.; Brown, T. [and others] 1999. The Penn

Swamp experiments: an overview. In: Shear, T.H.; Summerville, 

K.O., eds. Atlantic white-cedar: Ecology and management symposium. Gen. Tech. Rep. SRS–27. U.S. Forest Service. Southern 

Research Station. 82 p. 
73

Conference Attendees

1 Paul Ericksson 2 Kenneth O. Summerville 3 Bill Pickens 4 Eric Hinesley 5 Darren Rickwood 6 Steve Barry 7 Anne Hairston-Strang 8 Jennifer Cure 9 Phil Sheridan 

10 Steve Whittemore 11 Mike Petruncio 12 Aimlee Laderman 13 Scott Smith 14 Robert Williams 15 Keith Underwood 16 Doug Back 17 Roger Stallard 18 Johnathan Boynton 

19 Bill Sipple 20 Robert Heeren 21 Myvonwynn Hopton 22 Neil Pederson 23 Brian Martin 24 Kevin Thompson 25 David Walbeck 26 Bill Cure 27 Judy Broersma-Cole 

28 Lara Gengarelly 29 Lisa Hartrick 30 Keith Benedict 31 Jennifer Johnson 32 Mike Hart 33 William Zipse 34 John McCoy 35 Joe Swartz 36 Kristin Mylecraine 

37 Bob Belcher 38 Ed Crawford 39 Craig Clarke 40 George Zimmermann 41 Marianne Burke 
74

Index of Authors

Page

A

Atkinson, Robert B. 11

B

Broersma-Cole, Judy 62

C

Crawford, Edward R. 11

D

Day, Frank P. 11

Derby, Scott A. 17

Domozych, David S. 1

G

Gengarelly, Lara M. 31

Page

H

Hinesley, L. Eric 17

Hopton, H. Myvonwynn 22

K

Keeland, Bobby D. 44

Kuser, John E. 7, 38

L

Laderman, Aimlee D. 1

Lee, Thomas D. 31

M

McCoy, John W. 44

McMonigle, Dennis C. 54

Moulden, William B. 54

Mylecraine, Kristin A. 7, 38, 65

Page

P

Pederson, Neil 22

S

Smouse, Peter E. 38

U

Underwood, Keith R. 54

W

Wallace, David J. 54

Z

Zimmermann, George L. 7, 38, 65
Burke, Marianne K.; Sheridan, Philip, eds. 2005. Atlantic white cedar: 

ecology, restoration, and management: Proceedings of the Arlington Echo 

symposium. Gen. Tech. Rep. SRS-91. Asheville, NC: U.S. Department of 

Agriculture Forest Service, Southern Research Station. 74 p.

A symposium was held on the globally threatened and coastally restricted 

tree species, Atlantic white-cedar (Chamaecyparis thyoides (L) B.S.P.) at the 

Arlington Echo Outdoor Education Center, Millersville, MD, in June 2003. The 

theme of the symposium was “Uniting Forces for Action,” and participants in 

the symposium came from throughout the range of this species, from New 

England to the Gulf Coast. More than 15 papers and posters were presented 

addressing topics on community and ecosystem ecology of natural Atlantic 

white cedar (AWC) habitats, ecosystem restoration and stewardship efforts, 

the current range of the species, information on range-wide AWC genetics, 

and the long-term effects of various silvicultural manipulations on the entire 

vegetation community in AWC habitat.

Keywords: Atlantic white-cedar, Chamaecyparis thyoides, coastally restricted, 

ecosystem restoration, genetic variation.
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