Biological Report 85(7.21) July 1989 THE ECOLOGY OF ATLANTIC WHITE CEDAR WETLANDS: A COMMUNITY PROFILE Silva of North America. Tat. DXXIX. ~ EFamon-Jal CUPRESSUS THYOIDES. L .Z-: -ish and Wildlife Service ^il-^i) J.S. Department of the Interior DOCUM^T LIBRARY WuoJs Hole Occanographic Institution DOCUMENT LIBRARY Woods Hole Oceanographic Institution Copies of this publication may be obtained from the Publications Unit, U.S. Fish and Wildlife Service, 18th and C Streets, N.W., Mail Stop 1111, Arlington Square Building, Washington, EKT 20240, or may be purchased from the National Technical Information Service (NTIS), 5285 Port Royal Road, Springfield, VA 22161. o" z- ^- 10- * oi ■ CO . m '■ CD i '-' i O ; m ; <=! I CD Cover credit: Sprague, Sgt. Charles. 1896. The Silva of North America. Vol. X. Houghton Mifflin, Boston. Biological Report 85(7.21) July 1989 THE ECOLOGY OF ATLANTIC WHITE CEDAR WETLANDS: A COMMUNITY PROFILE by Aimlee D. Laderman Marine Biological Laboratory Woods Hole, MA 02543 Project Officers Michael Brody Edward Pendleton National Wetlands Research Center U.S. Fish and Wildlife Service 1010 Gause Boulevard Slidell. LA 70458 Prepared for U.S. Department of the Interior Fish and Wildlife Service Research and Development National Wetlands Research Center Washington, DC 20240 DOCUMEiMT LIBRARY Woods Hole Oceanographic Institution DISCLAIMER The mention of trade names does not constitute endorsement or recommendation for use by the Federal Government. Library of Congress Cataloging-in-Publication Data Laderman, Aimlee D. The ecology of Atlantic white cedar wetlands. (Biological report ; 85(7.21) "October 1988" Bibliography: p. Supt. of Docs, no.: I 49.89/2:85(7.21) 1. Wetland ecology-Atlantic States. 2. Atlantic white cedar-Atlantic States. 1. Brody, Michael. II. Pendleton, Edward C. 111. National Wetlands Research Center. IV. Title. V. Series: Biological report (Washington, D.C.) ; 85-7.21. QH104.5.A84L34 1988 574.5'26325'097 88-600399 This report may be cited as: Laderman, A.D. 1989. The ecology of the Atlantic white cedar wetlands: a community profile. U.S. Fish Wildl. Serv. Biol. Rep. 85(7.21). 114 pp. PREFACE This monograph on the ecology of Atlantic white cedar wetlands is one of a series of U.S. Fish and Wildlife Service profiles of important freshwater wetland ecosystems of the United States. The purpose of the profile is to describe the extent, components, functioning, history, and treatment of these wetlands. It is intended to provide a useful reference to relevant scientific information and a synthesis of the available literature. The world range of Atlantic white cedar (Chamaecyparis thyoides) is limited to a ribbon of freshwater wetlands within 200 km of the Atlantic and Gulf coasts of the United States, extending from mid-Maine to mid-Florida and Mississippi. Often in inaccessible sites and difficult to traverse, cedar wetlands contain distinctive suites of plant species. Highly valued as commercial timber since the early days of European colonization of the continent, the cedar and its habitat are rapidly disappearing. This profile describes the Atlantic white cedar and the bogs and swamps it dominates or co-dominates throughout its range, discussing interrelationships with other habitats, putative origins and migration patterns, substrate biogeochemistry, associated plant and animal species (with attention to those that are rare, endangered, or threatened regionally or nationally), and impacts of both natural and anthropogenic distur- bance. Research needs for each area are outlined. Chapters are devoted to the practices and problems of harvest and management, and to an examination of a large preserve recently acquired by the USFWS, the Alligator River National Wildlife Refuge in North Carolina. Ill CONVERSION FACTORS Metric to U.S. Customary Multiply millimeters (mm) centimeters (cm) meters (m) meters (m) kilometers (km) kilometers (km) square meters (m ) square kilometers (km hectares (ha) liters (I) cubic meters (m ) cubic meters (m ) milligrams (mg) grams (g) kilograms (kg) metric tons (t) metric tons (t) kilocalories (kcal) Celsius degrees (°C) inches inches feet (ft) fathoms statute miles (mi) nautical miles (nmi) square feet (ft^) square miles (mi ) acres gallons (gal) cubic feet (ft^) acre-feet ounces (oz) ounces (oz) pounds (lb) pounds (lb) short tons (ton) British thermal units (Btu) Fahrenheit degrees (°F) By To Obtain 0.03937 inches 0.3937 inches 3.281 feet 0.5468 fathoms 0.6214 statute miles 0.5396 nautical miles 10.76 square feet 0.3861 square miles 2.471 acres 0.2642 gallons 35.31 cubic feet 0.0008110 acre -feet 0.00003527 ounces 0.03527 ounces 2.205 pounds 2205.0 pounds 1.102 short tons 3.968 British thermal units 1.8(°C) + 32 Fahrenheit degrees stomary to Metric 25.40 millimeters 2.54 centimeters 0.3048 meters 1.829 meters 1.609 kilometers 1.852 kilometers 0.0929 square meters 2.590 square kilometers 0.4047 hectares 3.785 liters 0.02831 cubic meters 1233.0 cubic meters 28350.0 milligrams 28.35 grams 0.4536 kilograms 0.00045 metric tons 0.9072 metric tons 0.2520 kilocalories 0.5556 (°F - 32) Celsius degrees IV CONTENTS Eage PREFACE ijj CONVERSION FACTORS iv FIGURES vi TABLES vii ACKNOWLEDGMENTS '.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'. viii CHAPTER 1 INTRODUCTION 1.1 General Features 1 1.2 Classification 2 1 .3 Relationship with Adjacent Habitats 2 1.4 Origins and Migration of C/7amaecypar/s f/7yo/yes Forests 4 CHAPTER 2 REGIONAL OVERVIEW 2.1 Introduction 10 2.2 Glaciated Northeast 10 2.3 The North Coastal Plain 16 2.4 Virginia and the Carolinas 19 2.5 Juniper Swamps of the Southeast 22 CHAPTER 3 CHAMAECYPARIS THYOIDES: LIFE HISTORY AND ECOLOGY 3.1 Morphology 26 3.2 Silvical HalDits 27 CHAPTER 4 STRUCTURE AND FUNCTION OF THE SUBSTRATE 4.1 Hydrology 30 4.2 Water Chemistry 31 4.3 Soils 32 4.4 Production and Decomposition 33 4.5 Soil and Plant Tissue Chemistry 33 4.6 Interactions; Research Needed 34 CHAPTER 5 BIOLOGICAL COMPONENTS OF ATLANTIC WHITE CEDAR WETLANDS 5.1 Adaptations to the Wetland Environment 36 5.2 Flora 36 5.3 Fauna 37 5.4 Research Needs 45 CHAPTER 6 MANAGEMENT AND HARVEST 6.1 Impacts of Disturbance 46 6.2 Management 52 6.3 Commercial Use 54 6.4 Management Guidelines 57 6.5 The Federal Role 61 6.6 Research Requirements 61 CHAPTER 7 A CASE STUDY: ATLANTIC WHITE CEDAR WETLANDS IN DARE COUNTY, NORTH CAROLINA by J.H. Moore and A.D. Laderman 7.1 Overview 67 7.2 Physical Characteristics 70 7.3 Vegetation 72 7.4 Fauna 76 7.5 Management Problems and Options 78 REFERENCES 79 APPENDIXES: A Associated Flora: A Distribution Checklist by A.D. Laderman and D.B. Ward 91 B Associated Fauna 1 08 0 Hydric Soils 110 D Personal Communications and Acknowledgments: Reference 111 FIGURES Number Eage 1 Distribution of Chamaecyparis thyoides 1 2 Atlantic white cedar habitats in the palustrine system 3 3 Atlantic white cedar habitats in the riverine system 3 4 Cumloden Swamp, Falmouth, Massachusetts 4 5 Origins of glacial kettle and outwash cedar wetlands 5 6 Origins of backswamp cedar wetlands 5 7 Atlantic white cedar logs in exposed freshwater peat underlying a salt marsh 6 8 Atlantic white cedar migration routes 8 9 Macrofossil sediment stratigraphy in glaciated cedar wetlands 9 10 Distribution of glacial moraines and ice readvance localities in Northeastern United States . . . 11 11 Distribution of C/iamaecypar/'s thyoides in towns of the glaciated Northeastern United States. 12 12 Vegetationof the Hackensack Meadows 1819- 1896 17 13 Atlantic white cedar in the Delman/a 18 14 Presettlement range of Atlantic white cedar in the Carolinas 19 15 Location of Great Dismal Swamp National Wildlife Refuge 20 16 Section and plan views of a Carolina bay with Atlantic white cedars 23 17 Atlantic white cedar in southeastern United States 24 1 8 Cedar bordering a Florida sand-bottom creek 25 19 Morphology of CAiamaecypar/s frtyo/des 28 20 Radial annual growth cun/es of Atlantic white cedar 29 21 Water levels in six Rhode Island cedar swamps 31 22 Substrate cross section through a bog formerly dominated by Chamaecyparis thyoides .... 33 23 Flow diagram of cedar wetland dynamics 35 24 Composite illustrated flora: "Constant companions" of Atlantic white cedar 38 25 Effectsof fire during high water 47 26 Effects of fire during low water 48 27 Effects of permanent lowering of water level 49 28 Effects of flood 50 29 Effects of windthrow 51 30 Hydrological effects of ditches 53 31 Amphibious feller-buncher 56 32 Cedar regeneration after harvest 58 33 Management scheme 59 34 Forest management schematic for the Great Dismal Swamp 62 35 Vegetation communities of the Great Dismal: Current 64 36 Vegetation communities of the Great dismal: 25-yr projection, no-action option 65 37 Vegetation communities of the Great Dismal: 100-yr projection, no-action option 66 38 Alligator River National Wildlife Refuge 68 39 Soils of mainland Dare County 71 40 White cedar wetlands of mainland Dare County 74 VI TABLES Number Eage 1 Earliest records of Atlantic white cedar 7 2 Chamaecyparis thyoides: A summary of life fiistory 26 3 Physical characteristics of six Rhode Island cedar swamps 32 4 Water chemistry of cedar wetlands in New Jersey Pinelands 32 5 Plant tissue nutrient concentrations 34 6 Plant species of special concern 41 7 Bird species in two New Hampshire cedar swamps 42 8 Birds breeding in Great Dismal cedar stands 43 9 Breeding birds of Rhode Island cedar wetlands 44 10 Production of Atlantic white cedar: 1899-1945 54 1 1 Recent estimates of Atlantic white cedar timber volume 55 12 Vegetatbn cover in Atlantic white cedar stands in Dare County, North Carolina 75 13 Plant species associated with Atlantic white cedar in Dare County, North Carolina 76 14 Summer birds of Dare County, North Carolina white cedar habitats 77 VII ACKNOWLEDGMENTS Many colleagues have generously shared their knowledge and data with me. Their contributions are recognized at pertinent points in the text as personal communications; Appendix D identifies each contributor and the primary geographic region or scientific field addressed. I also wish to thank all contributors to the data base that became the first Flora Checklist (Laderman and Ward 1987), as noted in Appendix A, and the participants in the first Atlantic White Cedar Wetlands Symposium (Laderman 1987) which formed the basis for much of this profile. I am particularly grateful to the botanists who identified and checked regional species of special concern (as listed with Table 6), and to those colleagues who critically read sections of the manuscript, offered sugges- tions, and generously provided additional data, including: A. Belling, V. Carter, P. Gammon, M.K. Garrett, and J.H. f\/loore. Chapter7was co-authored by J. H. Moore, who diligently researched much unpublished material on Dare County cedar wetlands. D.B. Ward, co-author of the associated flora checklist (Appendix A), served as botanical referee and advisor for this community profile. All or parts of this manuscript were reviewed by the following: J. Golet, S. Leonard, S. Little, D. Lowry, and L. Stith. Allen, R. Andrews, A . Carter, F. I am grateful for much painstaking, attentive technical assistance: T. Laderman (Quincy, MA) and R. Colder (Photolab, Marine Biological Laboratory [MBL], Woods Hole, MA) prepared original illustrations; L. Colder (Photolab, MBL, Woods Hole, MA) Scientific Photographic Services (Edgewater, NJ) provided photographic services; J. Laderman and I. Laderman (MuScan Inc., Quincy, MA) programmed and produced the data bases; I. Laderman prepared tables and organized the physical text. L. Bjorklund, M. Parkin, H. Sather, and J. Shoemaker of USFWS assisted in obtaining technical materials. The manuscript was greatly improved by E. Pendleton, M. Brody, G. Farris, and B. Vairin of the National Wetlands Research Center, Slidell, LA. i VIII - CHAPTER 1 INTRODUCTION 1.1 GENERAL FEATURES Atlantic white cedar (Chamaecyparis thyoides) is geographically restricted to freshwater wetlands in a narrow band along the eastern coastal United States ranging from Maine to Mississippi (Figure 1). Cedar-dominated wetlands are most commonly called cedar swamps or cedar bogs, with a variety of other designations restricted to specific regions (e.g., "spungs" in the Pine Barrens [Moonsammy et al. 1987]; "juniper lights" in the Great Dismal [Kear- ney 1901]; "juniper bogs" throughout the south). Distinctive biotic assemblages dominated by Atlantic white cedar grow under conditions too ex- treme for the majority of temperate-dwelling or- ganisms. The shallow, dark, generally acid waters are low in nutrients and are buffered by complex or- ganic acids (e.g., humates, fulvic acids). Surficial deposits beneath cedar forests provide groundwater storage and discharge and recharge areas. Peats adsorb and absorb nutrients and pollutants (Gorham 1987), purifying and protecting ground and surface water with which they are in contact. In many regions, cedar wetlands are refugia for species that are rare, endangered, or threatened locally or nation- ally. The swamps form southern pockets for northern species at the geographic limits of their ranges, and similar northern pockets for southern species (Taylor 1915; New Jersey Pinelands Commission [NJPC] 1980), but many locally common aquatic plants and animals are absent from cedar swamps. Many species successful in these extreme environments have evolved unusual strategies for survival. The modest sum of research at the micro- scopic level in Atlantic white cedar wetlands reveals many symbiotic relationships of varying degree, ex- otic pigment combinations, and a range of metabo- lic, morphological, and temporal adaptations (Laderman 1980, 1987). However, the difficulty of gaining entry into cedar swamps, their limited geo- graphic distribution, and a general lack of awareness MILES 100 eoo ' — ' — I O 320 KILOMETCR* Figure 1 . Distribution of Chamaecyparis thyoides. Records were compiled from field observations, her- barium records, published sources, and personal communications. Counties in which Atlantic white cedar has been found are inked in black (from Lader- man 1982). of the existence of the forests and their contents have discouraged extensive investigation of this wealth of intriguing life strategies. European colonization and subsequent cen- turies of development have progressively so altered the landscape that much of the tree's original habitat was destroyed. Those stands that remain were in many cases protected only by the difficulty and high cost of penetrating the swamps. Cedar wetlands are increasingly encroached upon. They have been logged for their valuable lumber since the first ex- plorers set foot in the New World (Emerson 1981; Frost, unpubl.; Kalm 1753-1761) and have been drained for agriculture for more than two centuries (Frost 1987; Sipple 1971-1972). As areas become more heavily populated, industrial, commercial, and residential uses displace cedar wetlands where they are not protected by law (Laderman et al. 1987; Roman et al. 1987). Cedar peat is being experimen- tally mined as an energy source. Despite these multiple incursions, it is clear from the vigor of many stands that, with appropriate protection and, in some cases, aggressive manage- ment, cedars can successfully regenerate, and can repopulate many former cedar sites as well. 1.2 CLASSIFICATION Atlantic white cedar occurs almost ex- clusively with other hydrophytes on hydric soils in wetlands commonly known as swamps and bogs. It is also found, though rarely, near established cedar stands as a colonizer where there are hydrophytes but nonhydric soils. This may occur, for instance, at the margins of new impoundments or excavations where hydric soils have not yet developed. Atlantic white cedar forests may be composed exclusively of an even-aged monospecific stand of close-ranked trees, which is often referred to in the literature as "typical" for C. thyoides. In forests successfully managed for harvest and regeneration, as well as in many natural stands that originated after fire or flood, this is often the picture. However, in many natural or selectively harvested situations, cedars grow in un- even-aged mixed stands which provide a greater diversity of habitats that support a more species-rich fauna and flora. Animal and plant life, and the variety of cedar landscapes they inhabit, are described in Chapters 2, 5, and 7; the known flora and fauna are recorded in Appendixes A and B respectively. Under the U.S. Fish and Wildlife Service (USFWS) classification system (Cowardin et al. 1979) (Figures 2, 3), most cedar wetlands key out as: SYSTEf\4 Palustrine CLASS Forested Wetland SUBCLASS Needle-leaved Evergreen DOMINANCE TYPE Chamaecyparis thyoides; in mixed forests, common associates in the canopy are red maple {Acer rubrum), black gum {Nyssa syl- vatica), sweet bay {Magnolia virginiana), and one or more pine species: loblolly {Pinus taeda), white (P. strobus), or pitch pine (P. rigida) WATER REGIME Nontidal; Semipermanently or Seasonally Flooded, or Saturated WATER CHEMISTRY Fresh-Acid; rarely, Circum- neutral SOIL Organic; rarely. Mineral A detailed classification of various cedar wetlands is presented elsewhere (Laderman, un- publ.). Cedar swamps are situated shoreward of lakes, river or stream channels, or estuaries; on river floodplains; in isolated catchments; or on slopes. They may also occur (rarely) on bars or islands in lakes or rivers. Slightly elevated hummocks domi- nated by cedar are often interspersed with water- filled hollows in a repeating pattern that forms a readily identified functionally interrelated landscape. 1.3 RELATIONSHIP WITH ADJACENT HABITATS The USFWS (Cowardin et al. 1979) desig- nates the upland limits of wetlands as (1 ) the bound- ary between land with predominantly hydrophyte cover and land with predominantly mesophytic or xerophytic cover or (2) the boundary between predominantly hydric and nonhydric soil. The lower bounds of wetlands, both riverine and palustrine, lie at 2 m below low water or, if rooted plants grow beyond this depth, the border is at the deepwater edge of tree, shrub, or herbaceous emergent growth. In practice, however, consideration of the ecosystem for management must go beyond techni- cally defined borders. Indeed, the adjacent area may be a critical determinant in the structure and function of the entire wetland. The hydrological regime of a cedar wetland is a major determinant of the biota in both lotic (flowing) and lentic (nonflowing) systems. Mature Atlantic white cedars are adapted to a wide range of water depths, but rapid, prolonged change in water depth kills seedlings outright and stresses or kills mature specimens (see Figure 4) (Little 1950; Laderman 1980). In streamside, lakeside, and es- tuarine-border cedar swamps, the depth of water ad- jacent to and contiguous with a wetland is a major controlling influence on the wetland's water regime (Laderman, unpubl.). The impact of cedar wetlands on adjacent biota, hydrology, climate, etc., is at this time a matter of interest, but there are insufficient data for a clear i.'nderstanding of such effects. UPLAND PALUSTRIHE UPLAND PALUSTTtlNE UPLAND PALU9TRME -^ UPLAND m i 5 * n Ul o Ifc. 9 < 1 • ft ii o i a lU 8 < i| IE 2 lU z 3 UJ Si is Ul f r\'^^^ % ?I?T -- .'^ m t' k w •M(Ma«ZOil« *0{^ _1 ' j lA^ ^ ^ & ^^, J^y \ \^ ^ (. .H~ 1 1 91 k^^ *t7^K P^ Mi iiiliaH wATci^ > TEMPOHABIY FLOODED b SEASONALLY FLOODED »^ fW L» "> ■t-AVERAOE WATEf LOW WATER c SEMIPERMANENTLY FLOODED d INTERMITTENTLY EXPOSED ■ PERMANENTLY FLOODED f SATURATED Figure 2. Cedar habitats in the Paiustrine System. Atlantic white cedar forests usually occur in saturated (f) or temporarily flooded (a) zones on hummocks in freshwater wetland, in and below upland seepages, and in wet upland slopes adjacent to existing stands. Isolated, sometimes stunted cedars also emerge above a few saturated scrub-shrub or herbaceous savannah-like Paiustrine situations (adapted from Cowardin et al. 1979). Figure 3. Cedar habitats in the Riverine System. Atlantic white cedar forests most frequently occur as streamside swamps or backswamp wetlands in areas not subject to extensive or frequent scouring. Cedars also colonize wet upland slopes adjacent to existing stands; isolated, sometimes stunted cedars also emerge above a few saturated scrub-shrub or herbaceous savannah-like situations adjacent to streams (adapted from Cowardin et al. 1979). 1.4 ORIGINS AND MIGRATION OF CEDAR FORESTS 1.4.1 Glacial Effficts The advance and wasting of glaciers strong- ly influenced thie topograpfiy of the land both under the glaciers and over the entire continent's coastal area, due to direct glacial action, isostatic crustal movement, and major variations in sea level. During earlier interglacial periods, the northeast coast of the United States has been as far as 72 km further inland than today's shore; during the Wisconsin glaciation, sea level was as much as 60 to 80 m lower than its current height (Bloom 1983). The extent and timing of sea level rise and fall remains controversial (Bloom 1983). Glacial melting from 17,000 to 10,000 years before the present (B. R) led to the formation of glacial lakes and outwash beds of various sizes. Glacial lakebeds, kettleholes of the glacial moraine, and out- wash plain streambeds are landscape features that now support cedar communities in the Northeast (Figure 5). Further south, glacial meltwaters filled rivers and streams, the remnants of which now form the stream bank and backswamp wetlands (Figure 6) in the New Jersey Pine Barrens, the Delmarva penin- sula, Florida, and elsewhere. Such environments provide habitats for cedar growth. Conditions peculiar to the mid-Atlantic region are discussed in the Dare County case study (Chapter 7). Figure 4. Cumloden Swamp, Falmouth, Massachusetts. Permanent high water, the result of damming by a roadway, is causing the slow death of mature cedars. This picture was taken five years after the road was built, and one year before the death of the last cedars. Outwash plain Terminal moraine Figure 5. Origins of glacial kettle and outwash wet- lands. Conditions close to the margin of an almost stagnant ice sheet are shown diagrammatically in the upper block diagram. The lower diagram shows the same area after the ice is entirely gone. Cedar forests develop in kettles and along outwash channels (adapted from Strahler 1966). 1.4.2 Establishment and Survival Since the beginning of the current in- terglacial period, the long-term overall rise in sea level, averaging about one mm per year due to glacial melting and land subsidence, has played an impor- tant role in the development of many cedar wetlands. A. Redfield, (1 965) in the context of a rising sea level, proposed a model for the development of coastal salt marshes, which he extended to the development of coastal freshwater swamps (A. Redfield, pers. comm.). Redfield noted that near the seacoast, the rising sea level more or less keeps pace with peat ac- cumulation lifting the lens of freshwater above it. The effect of the rise in ground-water levels is that ex- isting wetlands remain wet, promoting the contin- uous presence of some cedar swamps for as much as 6,800 years (Belling 1977). Along the coast, seawater inundated fresh- water wetlands, giving rise to the accumulation of layers of saltmarsh peat superimposed on freshwater peat. Ample macrofossil evidence of the killing of cedar forests by saline incursion is found all along the I Block diagrams, very large vertical exaggeration I Uplands N.- NET DEPOSITION / ''Alluvial tan o( tributary Figure 6. Origins of backswamp cedar wetlands, (a) When sea level was below the present position, the river trenched its valley (b) As sea level rose, glacial meltwater poured down the river, creating a braided stream choked with sand and gravel, (c) Deposits of today's meandering river, established at a yet higher sea-level position, have buried the older braided stream deposits. Cedar wetlands develop in back- swamps and along small streambanks (adapted from Long 1974). Atlantic seaboard (Figure 7). Atlantic white cedar trunks, sometimes in the same position as in life or as they fell hundreds of years earlier, may be seen at low tides below saltmarsh turf on the coasts of New Hampshire, Massachusetts, New Jersey, Virginia, and elsewhere (Bartlett 1909; Heusser 1949, 1963; Belling 1977), and buried deep in off-shore marine sediments (Redfield and Rubin 1962). Figure 7. Atlantic white cedar logs in exposed freshwater peat underlying a salt marsh on Buzzard's Bay, Massachusetts. Note that many trunl*J*^ J-c *■ jtf T g-T rrc'x ii W\ / -2260 -^ -(5780)* Will Figure 8. Possible migration routes of Atlantic white cedar in the northeastern United States. Stars denote peat core analysis sites. Numbers indicate the approximate time at which C. thyoides became established (years before present, estimated by radiocarbon [R.C.] dating); first appearance is in parentheses (from Belling 1977). 8 DEPTH (dm.) 10- 30- 40 EO- 60- 70' 80- 90- t- Ul HI UJ CD Z K M 111 Z III (9 U < X u < o a. z e <2150 «3580 <3020 c380 <3770i □ HOODY PEAT FIBROUS PEAT WOODY/FIBROUS SEDGE PEAT MOSS PEAT GYTTJA D SAND CLAY WATER C5410 <6800 s4 ^— I CHARCOAL m CHAMAECYPARIS MACROFOSSILS NO R.a DATE *Z260 I "^syso '4021 Figure 9. Macrofossil sediment stratigraphy in glaciated cedar wetlands indicating Atlantic white cedar migration patterns. Radiocarbon (R.C.) dates: see notes, Figure 8 (from Belling 1977, and unpubl.). CHAPTER 2 REGIONAL OVERVIEW 2.1 INTRODUCTION The aspect of an Atlantic white cedar wet- land is so distinctive that the casual observer may think that ail cedar swamps are similar in physical structure and community composition. This is far from the truth when the cedar is examined over its en- tire range from north to south, from sea level to mountain hollow, from acidic glacial kettle to boggy flatwood or seepage sandhill. Cedar wetlands will be most clearly un- derstood by examining what we know of each ex- ample. Therefore, some typical or unusual sites are described below, including those at the farthest ex- tents of the cedar's range, the highest elevation cedar swamp (altitude: 457 m), a domed bog, swamps with a dense great laurel (Rhododendron maximum) understory, floating bog mats with dwarfed trees, a wetland in a deep fracture in bedrock, narrow stream-border Pinelands swamps, millponds, a Carolina bay, a sandhill seepage, and a sandy stream terrace. 2.2 GLACIATED NORTHEAST Atlantic white cedar wetlands dot a 130 km- wide band along the coastal region of the North- eastern United States from the southern extent of glaciation (Figure 10) along New York's Long Island and New Jersey's Hackensack Meadows, north to mid-Maine at 44° north latitude (Figure 11). Chamaecyparis thyoides grows from sea level to 457m elevation, but the great majority of stands are found between sea level and 50 m. It is probable that the distribution of the species was always restricted to sites too wet for most other northeastern trees. There is standing water in many northern cedar swamps for half the growing season or longer (Laderman et al. 1987; Golet and Lowry 1987); the soil is primarily organic; and ground water is highly acidic (pH 3.1 -5.5 [Laderman 1980; Golet and Lowry 1987]). 2.2.1 Climatology The growing season of Atlantic white cedar in the glaciated northeast ranges from 139 days in Maine to 211 days in northern New Jersey. Sum- mers are relatively cool and wet. Average maximum daily temperatures in July range between 13 and 16 °C. The extreme high temperatures, 39 to 41 °C, do not differ from those in the southernmost parts of the cedars' range, although the total degree- days and average temperatures differ markedly. The lowest temperatures in the glaciated cedar wetland area range from -40 °C in Maine to -22 °C in New Jersey Average annual precipitation is between 101 and 119 cm (data from Ruffnerand Bair 1981). 2.2.2 Distribution Generally Chamaecyparis decreases in abun- dance with increasing distance from the coast. Low tides and storms reveal cedar stumps buried under saltmarsh peat near the coast from Kittery Point, Maine to New Jersey, evidence of the slow rise of sea level in this region (Redfield and Rubin 1962). Atlan- tic white cedar was far more plentiful in each of these states a few hundred years ago, but there is no evidence that its range ever extended significantly to the west or north of its current extent. In New England, Atlantic white cedar is most abundant in southeastern Massachusetts, Rhode Is- land, and eastern Connecticut (Golet and Lowry 1987; Sorrieand Woolsey 1987; Laderman, unpubl.). Its distribution (Figure 11) appears to be closely re- lated to glacial features such as moraine hollows, gla- cial kettles, or old lake beds. There are 1 1 known Chamaecyparis stands in Maine (Eastman, unpubl.; B. Vickery, pers. comm.) and about twice that number in New Hampshire (H. Baldwin, pers. comm.; F Brackley, pers. comm.; R Auger, pers. comm.). In Massachusetts, cedar swamps are found in all but three of the 64 towns in Bristol, Plymouth, and Barnstable (the State's three major southeast counties), and approximately 30 10 ^" Moroines «j^ Ice Reodvances Inferred Glocial Margin •••• Recessional Moraines Long Island Figure 1 0. Distribution of glacial moraines and ice readvance localities in the northeastern United States (from Laderman et al. 1987, redrawn from Larson and Stone 1982). 11 stands are scattered north and west of Boston (Sorrie and Woolsey 1987). Rhode Island contains more than 1 30 stands in four of the State's five counties (D. Lowry, pers. comm.). There are records of 39 'C. thy- oides wetlands extant in Connecticut (K. Metzler, pers. comm.); a half century ago Noyes (1939) counted 86 stands, 72% of them in the two easternmost counties of New London and Windham. Two small cedar bogs are all that remain in mainland New York State (Lynn 1984), but many stands persist in southeastern Long Island (J. Turner, pers. comm.). While extensive cedar wetlands are found south of the limit of glaciation in the Pine Barrens of southern New Jersey, only seven are known from the glaciated part of the State (D. Snyder pers. comm.). Early reports (e.g., John Bartram's 18th century letters [Darlington 1849]; Kalm's 1753-1761 diary [Benson 1966]) described rich cedar forests in the eastern tip of Pennsylvania at the New Jersey border, but Chamaecyparis has been extirpated in Pennsylvania for many years (illick 1928). Figure 1 1 . The historical distribution of C. thyoides in towns of the glaciated northeastern United States (from Laderman et al. 1987). 12 Throughout the glaciated Northeast, only a fraction of earlier stands remains. Information on the current status and location of many sites is available from the Natural Heritage Programs, the Nature Con- servancy, and State natural diversity data bases. The following descriptions of stands are adapted from Laderman et al. (1987). t^aine. The northern and eastern edges of the worldwide native range of C. thyoides are in the state of Maine (Rossbach 1936). Maine's eleven cedar stands are scattered from Knox County south- ward to the New Hampshire border, generally within 20 km, and never more than 48 km, from the Atlantic coast. They are found among low hills, between ridges, and along lakes and swampy valleys with meandering streams (Eastman 1977). Appleton Bog, at 44° 20' north latitude the northernmost site of the tree's range, was discovered in 1931 by Rossbach (1936). The 92 ha site contains well -developed Sphagnum -carpeted hummock and hollow topography dominated by vigorously reproducing, healthy cedars (Worley 1976). Hum- mock tops lie above the water table most of the grow- ing season; in droughts, the water table remains within a few centimeters of the surface of the hollows. There are no streamcourses within the cedar- dominated area, and there is neither inflow nor out- flow of surface water Sixteen hectares last logged in the 1950's are vigorously regenerating. The cedars form dense, pure stands, averaging 15 to 40 cm in diameter at breast height (dbh) ; the maximum height seen was ca. 1 8 m (Worley 1 976). Potamogeton con- fervoides, a pondweed rare in Maine, grew in a pond within the bog a decade ago but may have been re- cently extirpated as it has not been found in more re- cent explorations (G. Rossbach, unpubl. letter). Northport, in Waldo County, at 69° 01' west longitude is the easternmost location known for C. thyoides; it contains a strikingly different cedar site just a few km southeast of Appleton Bog. In 1930, Rossbach (1936) discovered stunted cedars scat- tered and clumped on a 0.5 km-wide bog mat floating at one end of Knight's Pond. It has apparently changed little in this half century. Mature cedars (some only 15 cm tall) share the tufted mat surface with stunted white pine {Pinus strobus), black spruce {Picea mariana), tamarack (Larix laricina), and a rich variety of ericaceous shrubs, carnivorous herbs, and Sphagnum mosses (B. Vickery and A. Laderman, unpubl. field notes). Saco Heath, northwest of Saco, York Coun- ty, is the only domed bog known to contain Chamaecyparis thyoides, and is possibly the southernmost raised coalesced peatland in the east- ern United States. Saco is the only large Sphagnum bog in southern Maine, and is one of the southernmost Atlantic coast breeding sites known for the palm warbler (Dendroica palmarum) (H. Tyler and M. Michener, pers. comm.). The earliest reports of C. thyoides in Maine (Goodale 1 861 ) indicated that it grew in York and Kit- tery at the southernmost tip of Maine's seacoast, where now only gnarled stumps of a drowned cedar forest are sometimes visible at extreme low tide. New Hampshire. More than twenty Atlantic white cedar stands are scattered through five of New Hampshire's ten counties (P. Auger, pers. comm.; H. Baldwin, pers. comm.). A few rare high- altitude Chamaecyparis swamps are found here. Robb Reservoir in Stoddard at 388 m is second in el- evation only to High Point, New Jersey. At least seven stands are found above 250 m, six of them growing in Hillsborough County (Svenson 1929; Baldwin 1961, 1963, 1965, and pers. comm.; F. Brackley, pers. comm.). Little has been published about the state's cedar wetlands; their continual loss is documented repeatedly in Baldwin's short notes (1961, 1963, 1965) and unpublished letters, and in unpublished records of the New England Nature Conservancy and the Society for the Protection of New Hampshire's Forests. Massachusetts. In Massachusetts, Atlantic white cedar is commonest south of Boston, par- ticularly in Plymouth and Bristol counties. Many acres of cedar swamp still exist here, although they are being encroached upon by urbanization. Cran- berry bogs were often created from cedar wetlands, but it is difficult to determine how many acres histori- cally supported Atlantic white cedar Farther west, there are fewer wetlands and less optimal conditions for cedar growth. In some areas of western Mas- sachusetts, in the Connecticut River valley and in northern Worcester County, cedars usually occur within black spruce and larch forests in a more boreal setting. On Cape Cod, cedar bogs are sparsely dis- tributed from Provincetown to the Cape Cod Canal, primarily in glacial kettles. Diaries of early explorers and colonists (Archer 1602 and Brereton 1602 [in Emerson 1981]; Emerson 1981) tell of many thick cedar stands on the Cape as well as on the adjacent Elizabeth Islands, where only a single cedar swamp remains today. Despite the white cedar's historic abun- dance in Massachusetts, few studies of the state's cedar wetlands have been published. The Mas- sachusetts Natural Heritage Program is currently preparing an inventory of the natural areas of the 13 state and is gathering data hitherto unavailable. Even as the information is collected, large tracts are being threatened by major development. Occurrences of cedar in the state may be grouped in three broad classes (1) pure forest stands with little other canopy vegetation (the most common cedar community of the mainland), (2) mixed stands, with cedar occurring among other wetland trees, primarily red maple, and (3) in kettles with an open body of water surrounded by a succession of zones in which cedar is one of the concentric rings of vegetation. An example of the vegetation sequence sur- rounding a kettle pond would be: a band of emergent swamp loosestrife (Decodon verticillatus) rimmed by a Sphagnum-based mat, on which there is a suc- cession of narrow shrub zones starting with perhaps some dwarf huckleberry (Gaylussacia dumosa), leatherleaf (Chamaedaphne calyculata), blueberry (Vaccinium spp.), and swamp azalea (Rhododendron viscosum), which sharply grade into Atlantic white cedar, and finally white pine, hem- lock, and upland species. Some typical plants of the open Sphagnum zone would be pitcher plant (Sar- racenia purpurea), sundew (Drosera Intermedia), and occasional orchids such as rose pogonia {Pogonia ophioglossoides) or grass pink {Calopogon pulchellus). A variation of this vegetation type is found on Cape Cod, where cedars may occupy relatively flat- surfaced kettles rimmed by a moat slightly deeper than the body of the wetland. The cedars, often the sole canopy tree, cluster on small hummocks that are spotted over the entire basin. The concentric vegeta- tion pattern is condensed on each hummock, with ericaceous shrubs, sweet pepperbush {Clethra al- nifolia), and ferns in tight array rising from a sphag- nous carpet that continues into the water of the hollows. Species otherwise rare in southern New England are found in Chamaecyparis wetlands, e.g., dwarf mistletoe (Arceuthobium pusillum), a tiny flowering parasite that causes deformation and death of at least the branches of the black spruce on which it grows; and heartleaf twayblade (Listera cor- data), a northern species at its southern limit in Cape Cod (the only known extant location in the state). The northern parula warbler (Parula americana) in Massachusetts now breeds primarily in a few cedar wetlands, as the hanging lichen Usnea, its favored nesting material, is fast disappearing outside the cedar swamps. Rhode Island. In Rhode Island, Atlantic white cedar is most abundant west of Narragansett Bay, particularly in Washington County and in the western sections of Kent and Providence Counties (D. Lowry and F. Golet, pers. comm.) There is very lit- tle cedar on the east side of the Bay although place names such as "Cedar Swamp" suggest that the species was more common there in the past. The largest stands of cedar occur within the state's three largest wetlands, all of which are situated on broad expanses of stratified drift less than 30 m above sea level. Cedar forest covers 240 ha of the 870-ha Chapman Swamp in Westerly. The remainder of this highly diverse wetland includes deciduous forest, shrub swamp, bog, marsh, and open water. Two-thirds of the 390-ha Indian Cedar Swamp in Charlestown supports cedar, but red maple {Acer rubrum) is the dominant species in most of the stands in which cedar occurs. In the Great Swamp, which occupies 1200 ha in South Kingstown, Richmond, and Charlestown, cedar covers some 90 ha; the great majority of this wetland consists of deciduous forest and shrub swamp. Smaller stands of cedar are commonly found in glacial kettles (ice-block basins) which formed in stratified drift or in thick deposits of morainal material. A highly unusual stand of Atlantic white cedar occupies a kettle situated in outwash at the edge of Factory Pond, 9 m above sea level in South Kingstown. The trees in this 5-ha "forest" are 80 years old, but only 1 -1 .5 m tall. Bordered by the pond on one side, the stand is separated from the ad- jacent upland by a moat of open water and a quaking mat of low shrubs. The surface of this dwarf cedar bog is carpeted throughout with Sphagnum moss. The water table stays within a few centimeters of the surface all year, and the pH of the soil water drops as low as 3.1 . The soil is a poorly decomposed, fibric peat. Growing in association with the cedars are leatherleaf, cranberries (Vaccinium macrocarpon, V. oxycoccos), cottongrass (Eriophorum sp.), and pitcher plant. At its deepest point, this kettle contains 9 m of peat. Cedar wetlands along the Connecticut bor- der in western Rhode Island generally lie at eleva- tions ranging from 90 to 1 80 m. Most of these have developed over valley train deposits of stratified drift or in association with ice contact deposits. A very small percentage of these swamps lie directly on bedrock or on unstratified drift (more commonly known as glacial till). Most wetland basins in till or bedrock tend to be small, and peat deposits seldom exceed 2-3 m in thickness. Red maple and black gum (Nyssa sylvatica) are the two tree species most commonly associated with Atlantic white cedar throughout Rhode Island, but eastern hemlock (Tsuga canadensis) is an important associate in many of the swamps lying 14 above 90 m. In a small number of wetlands in north- western Rhode Island, cedar grows in association with two boreal species, black spruce (Picea mariana) and larch {Larix larina) (R. Enser, pers. comm.). Great laurel (Rhododendron maximum), a broad-leaved evergreen shrub which is common in upland areas of the southern Appalachians (Fernald 1 950), is locally common as an understory species in both deciduous and evergreen wetland forests in southern Rhode Island and nearby Connecticut. This shrub grows to a height of 2.5 to 4.5 m and often forms such dense tangles that travel through the swamps is exceedingly difficult. As a result of the deep shade created by a dense canopy of cedar and a thick understory of great laurel, herbs are scarce to nonexistent in these swamps (Lowry 1984). A striking example of the Atlantic white cedar-great laurel association can be seen in the Ell Pond-Long Pond Natural Areas Complex near the Connecticut line in Hopkinton. There a dense, 90- year old cedar forest containing hemlock as well as great laurel borders the northern and western shores of Ell Pond, which lies in a deep fracture in the local bedrock. The surrounding relief is rugged and bedrock outcrops are numerous. Between the forest and the water's edge is a narrow bog mat dominated by leatherleaf. Peat thickness ranges from 4 m in the forest interior to 8-9 m at the water's edge. The Ell Pond stand, which averages 13 m in height, is 98 m above sea level. Ell Pond and its associated wet- lands represent Rhode Island's only National Natural Landmark. For further description of Rhode Island sites, see Lowry (1984) and Golet and Lowry (1987). Connecticut. Thirty-nine cedar wetlands, all but six of them east of the Connecticut River, are known to contain living cedar in Connecticut at present (K. Metzler, pers. comm.). Some sites are re- ported to be in near-pristine condition, some are trampled and debris-strewn, and some are still being logged for cedar A few are in public ownership, but most have no active conservation management. Two cedar wetlands were designated as Na- tional Natural Landmarks in 1973: Chester Cedar Swamp, and Pachaug Great Meadow in Voluntown. A cedar log walkway and marked trail traverse a sec- tion of the Pachaug preserve containing over 200 ha of cedar in an approximately 350 ha swamp-bog- sedge meadow complex (K. Metzler, pers. comm.) drained by the Pachaug River Pachaug and at least two other stands are known to contain sizable, vig- orous, dense great laurel populations (Ledyard Cedar Swamp, and Bell Cedar Swamp in North Stonington) (K. Metzler, pers. comm.). Creeping snowberry [Gaulthen'a hispidula) is reputed to grow in one privately-owned swamp. North Windham Peat Bog contains a dense 30-ha white cedar swamp with black spruce, unusual in Connecticut. It is a combination not seen south of this point except in the montane Sterling Forest, New York and High Point, New Jersey forests (Laderman, unpubl.). Monographs by Nichols (1913) and Taylor (1915), and a master's thesis by Noyes (1939) con- stitute the major sources of historical botanical data about Chamaecypahs in the state. The papers con- tain lists of associated species, brief site descrip- tions, and maps, indicating that of 86 cedar stands known at the time, 85% were east of the Connecticut River New York State. Before the agricultural and suburban development of Long Island, cedar swamps were believed to form an almost continuous chain from Brooklyn to Montauk Point (Nichols 1913), clustered along the southern edge of the ter- minal moraine that forms the island's spine. As civ- ilization spread, cedar wetlands declined drastically (Torrey 1843; Harper 1907; Bicknell 1908; Taylor 1916). The primary cause of cedar loss in Nassau County was lowering of the water table when streams were dammed to create reservoirs for the rapidly ex- panding populace. Nassau County today holds few mature cedars, with no evidence of regeneration (J. Turner, pers. comm.). In Suffolk County, earlier in this century, many wetlands were lumbered, drained, and cleared for farming. Those remaining are being rapidly replaced by summer resorts and second homes. The county now contains only 11 known cedar stands, most of them quite small. Southampton Township harbors the greatest abundance of cedars in Long Island. The largest New York wetland com- plex containing Chamaecyparis is in a 40-ha area of Southampton's Cranberry Bog County Park, along the southern reaches of the Peconic River (J. Turner, pers. comm.). Outside Long Island, the only cedar stands remaining in the state are two small bogs in Sterling Forest, each less than 0.5 ha (Lynn 1984; Lynn and Karlin 1985). New Jersey. Glaciated New Jersey has only seven known cedar stands, but it bears the distinc- tion of harboring an Atlantic white cedar swamp in High Point at the greatest altitude recorded for the species. Its elevation of 457 m exceeds that of the next highest stand (in New Hampshire) by 69 m. Only three northern New Jersey sites contain more than a few trees at present: High Point and Wawayanda in Sussex County in the far northwest 15 corner of the state, and Uttertown in adjacent Passaic County (D. Snyder, pers. comm). At least eight other sites in glaciated New Jersey had once supported cedar (Britton 1889; Gifford 1896; Heusser 1963). The higher elevation areas show no ev- idence of the existence of earlier, more extensive stands. The Hackensack Meadows, however, was covered by great cedar wetlands which were first described in botanical detail by Torrey and his co- workers (1819). In the mid-eighteenth century, huge fires were set in these swamps to eliminate hiding- places for bandits terrorizing the region. At about the same time, extensive systems of dikes, ditches, and tide-gates were built in a fruitless series of attempts to cultivate the wetlands. Chamaecyparis is now completely extirpated in the Hackensack Meadows. The region's original botanical richness and its sub- sequent decline were recorded by a series of eminent naturalists (reviewed and correlated by Sipple (1 971 - 1972)(Figure12). The high-elevation cedar swamp in High Point, protected by the State of New Jersey since 1923, is now buffered by 516 ha of the Kuser Natural Area (New Jersey Bureau of Forest Management 1984). Its 4-6 ha of mixed dense coniferous-decid- uous forest grow on a few dm of woody peat (Belling 1977). Great laurel forms most of the dense under- growth in deep shade; in more open sections, other heath shrubs (primarily Ericaceae) predominate. Herbs are relatively rare and scattered (Niering 1 953; Belling unpubl.). The cedar forests of glaciated New Jersey strongly resemble the most northerly stands of the species. The only report for balsam fir {Abies bal- samea) in the state, and its sole sighting in a Chamaecyparis association outside of Maine is at High Point (Belling 1977). Larch, black spruce, and hemlock occur with C. thyoides only within the glaciated portion of the cedar's range. 2.3 THE NORTH COASTAL PLAIN 2.3.1 Jersey Pinelands Most of New Jersey's Atlantic white cedar swamps are located in the state's southern pinelands, historically called the Pine Barrens. Cedar stands presently occupy about 8,680 ha, 2% of this 445,000 ha landscape (Roman and Good 1983). Ac- counts of Stone (1911), Harshberger (1916) and Wacker (1979) suggest that cedar swamp acreage has been declining since European settlement. His- torical estimates, although widely variable, docu- ment the reduction from a maximum of 40,500 ha (Vermeuleand Pinchot 1900; Cottrell 1929; Ferguson and Meyer 1974). Southern New Jersey's coastal plain is char- acterized by low relief with streams slowly flowing through an unconsolidated sand/gravel substrate. The cedar swamps generally form narrow borders on streams from headwaters to tidal freshwater Of 626 discrete cedar swamp patches in the Pinelands, over 90% are less than or equal to 40 ha. A few cedar swamps over 200 ha in area also occur (Zampella 1987). Poorly drained muck (fine organic) soils usually underlie the Pinelands cedar swamps. Muck depth, generally shallower than in northern glaciated Jersey, is often less than 1 m, ranging occasionally to 3 m. (Waksman et al. 1943). Undisturbed mature Pinelands cedar stands are dense and even aged, with canopies 15-18 m high (McCormick 1979). Pitch pine {Pinus rigida) is an occasional co-dominant. The understory of red maple, black gum {Nyssa sylvatica), and sweet bay (Magnolia virginiana) may be continuous, relatively sparse, or absent. Highbush blueberry (Vaccinium corymbosum) , dangleberry (Gaylussacia frondosa), swamp azalea (Rtiododendron viscosum), sweet pepperbush (Clettira ainifolia), fetterbush (Lyonia mariana), and bayberry (Myrica pensylvanica) are the commonest species in the shrub layer Hollows are conspicuously carpeted with Sphagnum spp. The herbaceous flora is usually sparse, but diverse. Sundews (Drosera spp.), bladderworts (Utricularia spp.), pitcher plant, and chain fern (Woodwardia vir- ginica) are the commonest herbs. In New Jersey, the rare curly grass fern (Schizaea pusilla) is found only in the Pine Barrens. Reviews of the literature and much detailed information about Atlantic white cedar in the Jersey Pinelands are contained in the Pinelands National Reserve Management Plan (New Jersey Pinelands Commission [NJPC] 1980); Roman et al. (1987, and unpubl.); and Forman (1979). Buchholz and Good (1 982) prepared extensive annotated Pinelands bibli- ographies with sections indexed for Chamaecyparis. Disturbances such as fire, storms (windthrow, ice damage), cutting, flooding, deer browse on young stands, beaver damming, cranber- ry cultivation, and subsequent abandonment cause considerable variation in the vegetation structure and species composition of Pinelands cedar swamps. Such disturbances may be followed by the growth of cedars in pure stands, in mixed cedar- 16 dgef leld Ne Figure 12. Vegetation oftheHackensack Meadows circa 1819-1 896. "Cedar swamp bottom" indicates former cedar land, or cedars dying in 1896 (from Sipple 1971-72, after Vermeule 1897). 17 hardwood stands, or as isolated trees or clusters in a shrub-dominated landscape (Little 1979; Forman 1979). Decline of cedar swamps. It must be em- phasized that the general trend has been toward con- version to other wetland types. In addition to disturbances noted earlier, the decline of the Pinelands cedar wetlands has been hastened by rising sea level, flooding for cranberry production, creation of industry-related reservoirs and recrea- tional lakes, and drainage for agriculture and residen- tial development (Roman et al. 1987). The harvest and management of Atlantic white cedar in the Pinelands are discussed in detail in Chapter 6. 2.3.2 The Delmarva Peninsula Atlantic white cedar exists today on the Del- marva Peninsula in remnant stands that represent only a fraction of the species' former geographic range (Figure 13). For literature review and further detail, see Dill et al. (1987) and Dill et al. (unpubl.), from which the following discussion was extracted. Just 322 km long and only 113 km at its widest, the Delmarva peninsula contains all three Delaware counties, nine Eastern Shore Maryland counties, and two Eastern Shore Virginia counties. It is bounded on the north by Pennsylvania; on the east by the Delaware River, Delaware Bay, and the Atlantic Ocean; and on the west by the Susquehanna River and Chesapeake Bay. There are two distinct geo- graphic provinces: (1) the Piedmont Plateau, with rocky, wooded hillsides and rich alluvial stream val- leys and (2) the Atlantic Coastal Plain, with soils of clays, silts, sands, and gravels. The Fall Zone cuts across the northern por- tion of the peninsula in a narrow northeast to south- west band. Here Piedmont streams tumble as much as 42.7 m to the Inner Coastal Plain below. All Atlan- tic white cedar sites in Delmarva are located below the Fall Zone, with a few stands on the Inner Coastal Plain, and none on the Piedmont Plateau. A catalog of 58 present and historic sites in- dicates that white cedar now grows in Kent and Sus- sex Counties, Delaware; Kent, Queen Ann's, Talbot, Dorchester, Wicomico, and Worcester Counties, Maryland; and Accomac County, Virginia. Cedar wetlands are found in six watersheds draining into Delaware Bay: three drain directly in the Atlantic Ocean, and five drain into the Chesapeake Bay All sites are associated with acid water (ca. pH 5) on the Coastal Plain, where cedar is found primarily along non-tidal river courses, with a few on pond margins and in isolated swamps. Cedar presence is closely correlated with Delaware soil types (Seyfried 1985). The average annual temperature is 13° C; average annual precipitation is 1 14.3 cm. For most of the year, winds are west to northwest, with a more southerly flow in summer. f.'*- fall zone population Figure 13. The probable historical range of Atlantic white cedar in the Delmarva peninsula, reconstructed from herbarium records and personal communications (from Dill et al. 1987). 18 Delmarva habitats are collectively char- acterized by the presence of 1 6 plant taxa variously noted as rare in Delaware, Maryland, and Virginia lists (see Chapter 5). Of particular interest is the associa- tion of several carnivorous plants; the nationally rare swamp pink {Helonias bullata) ; and the Delmarva en- demic, seaside alder {AInus maritima). Human im- pacts have extended over three centuries and include millpond construction, fire, siltation, drainage and channelization, bulkheading of riverfront proper- ty, pollution, and commercial timbering. Existing stands are seen as prime habitats for natural area conservation. 2.4 VIRGINIA AND THE CAROLINAS On the Virginia mainland, Atlantic white cedar is found only in the Great Dismal Swamp. Virginia's Eastern Shore stands are considered with the rest of the Delmarva area in Section 2.3.2. The historical range of Chamaecyparis in North and South Carolina has been documented by Frost (1987 and unpubl.)(Figure 14). Eastern North Carolina is the subject of a case study, Chapter 7. 2.4.1 The Great Dismal Swamp in Virginia and North Carolina The name "Dismal Swamp" originated in colonial days for the over 404,000 undrained hec- tares between the James River in southeastern Vir- ginia and the Albemarle Sound in North Carolina (Oaks and Whitehead 1979). The Great Dismal Swamp National Wildlife Refuge (GDSNWR), estab- lished in 1 973, occupies a 43,000 ha rectangular rem- nant of the former swamp. Located approximately 48 km from the At- lantic Ocean, the refuge lies between the cities of Suf- folk and Chesapeake in Tidewater Virginia and within Gates, Camden, and Pasquotank Counties in North Carolina (Figure 15). It is delineated on the north by U.S. Route 58, on the south by U. S. Route 1 58, on the east by Route 17, and on the west by the Suffolk Scarp. Where no other source is indicated, the fol- lowing discussion is drawn from the draft environ- mental impact statement (EIS) for the Great Dismal Swamp National Wildlife Refuge Master Plan (USFWS 1986b). r— — -= — TTriI?t3im_S.A.u. ■'■^^Rv-'^ SOUTH- •M;^)^ )"c>>?>K^ :. "j; A^ cv. '\s"^"t <.= Ar -^ V< »E E / .X 'i.y...--:-> \ \ J..( 7 :'•'. ".••'1 • ,.''"••■. J V •■ />' RECENT SOURCES C Buell & Cain 1943 F FroBt 1984 L Wells 1946 M Lynch 1984 R Radford et al. 1968 S SC Heritage Trust 1984 T Little 1971 HISTORICAL SOURCES A Aahe 1894 A2 Ashe 1893 B Byrd 1728 E Elliott 1824 H Hale 1883 O Anon. 1907 P Plnchot & Ashe 1897 U Ruffln 1861 W Bannister et al. 1903 Y Wood & McCarthy 1886 Z Ntchaux 1857 * JUNIPER PLACE NAMES JUNIPER BAY JUNIPER BRANCH JUNIPER CREEK JUNIPER RUN JUNIPER SWAMP Figure 14. Historical range of Atlantic white cedar in the Carolinas. Letters in each county refer to sources in the literature, herbaria, or place names, as documented in Frost (1987, and unpubl.) (from Frost 1987). 19 Figure 15. Great Dismal Swamp National Wildlife Refuge, Virginia and North Carolina (from USFWS 1986b). Development and geography. Although paleogeography of the Atlantic coast is still the sub- ject of debate (e.g., Watts and Stuiver 1980; Bloom 1983), it is generally believed that the Dismal Swamp probably first developed along coastal streams 1 1,000 to 12,000 years ago (Oaks and Coch 1973; USFWS 1986b). Palynological evidence (Whitehead 1965) indicates that full-glacial boreal spruce-pine forests were succeeded by pine-spruce forests and, toward the end of the late-glacial, by northern hardwood forests. During the early postglacial period, the forests were dominated by hardwoods that currently grow in the region. A variable cypress- gum forest has characterized the Dismal Swamp for the past 3500 years (Whitehead and Oaks 1979). The wetland expanded along watercourses, and peat accumulated until by 3,500 years B.R, peat had blan- keted the present-day Dismal Swamp. Whitehead (1965) and Whitehead and Oaks (1979) found that cypress (Taxodium) and cedar pollens first appear in the peat about 6,500 yrs B.P, increasing to 60% of pollens by 3,000 yrs B.P Since then, cypress and cedar have comprised 40°/o-60% of the peat pollen profile. (Chamaecyparis pollens were not counted separately.) Climate, physiography, topography, and geology. Temperatures, precipitation patterns, and humidity are similar to that of Dare County, North Carolina (see Chapter 7). The Dismal Swamp lies on the Atlantic Coastal Plain, between the Suffolk Scarp and the Deep Creek Swale. Elevations range from 4.6 to 7.6 m. The topography slopes gently to the east at the rate of 0.2 m/km (Carter 1987). The geologic formation most intimately as- sociated with the Dismal Swamp water budget, which accounts for the majority of water that upwells in the swamp, is a shallow aquifer composed of coar- sely-grained to finely-grained old marine sands (Lichtlerand Walker 1979). Formerly termed the Nor- folk Formation (now recognized as the Shirley and Tabb Formations [Carter 1987]), this is a water-bear- ing layer through which water moves laterally. Soils. The soils of the cedar swamps are black, fine-grained, highly decomposed mucky peats characterized by poor drainage and high acidity, with mean annual soil temperatures between 15 and 22 °C. Undecomposed logs and stumps are buried in the decomposed organic material at depths ranging from a few centimeters to 1 .5 m (Lichter and Walker 1979; Otte 1981). Permeability varies with the composition of the subsoil. Hydrology. As the wetland district's hydrological functions are interrelated, and data restricted to the cedar stands are unavailable, infor- mation on the water regime of the entire Dismal Swamp (Lichtlerand Walker 1979; USFWS 1986b; R Gammon, pers. comm.) is examined here. Inflow. Ground water (a major influence) flows into the swamp from the west through perme- able layers that interface with the shallow "Norfolk" aquifer The average annual precipitation is 127 cm (U.S. Weather Bureau 1926-1975, quoted in USFWS 1 986b). Surface water inflow from the west along the Suffolk Scarp is a minor influence, with most of it moving out rapidly through streams and ditches. Water loss. Evapotranspiration (the com- bined effects of evaporation and transpiration) in areas upstream (i.e., west) of the swamp severely limits inflow during summer months despite high rainfall. In the summer months, evapotranspiration probably accounts for the biggest portion of water re- moval from the swamp ecosystem. It exceeds rain- fall during the growing season and causes a lowering 20 of water levels in the swamp throughout the summer. Surface water runoff through the swamp is also a major output event. Over the last two centuries natural outiflow patterns have been almost complete- ly obliterated, and surface water now drains from the swamp through channelized outlets. Ground-water discharge is significant: where the upper confining layer is absent, freshwater wells up into the overlying peat and Is removed by evapotranspiration; where the aquifer is breached, ground water drains from the swamp as surface flow through outlet channels. In the latter case, the water is lost to the swamp; it may be a major factor in the lowering of the swamp's general water level. The net effect of all the modifications to the swamp's surface and ground water systems is that the majority of the peat soils in the swamp are drier for a longer period of the annual cycle than would occur naturally (Lichtler and Walker 1979; USFWS 1986b). Surface water. The water has a dark tannic color, low mineral content, and a pH of 3.5 - 6.7. Some areas have high iron and free carbon dioxide content. Sediment from upstream agricultural and timber lands, runoff from hog operations, and fer- tilizers and pesticides used on corn, soybeans, and peanuts are potential sources of surface water pollu- tion. The proximity of the shallow aquifer to the sur- face makes it highly susceptible to contamination from agricultural, industrial, and domestic runoff. Biota. Atlantic white cedar covers 3,000 ha or 7% of the refuge, primarily in the south central por- tion of the swamp, with a few stands north of Lake Drummond. At present, it is impossible to estimate the area occupied by cedar a century or more earlier (A. Carter, pers. comm.). In the Great Dismal, cedar grows primarily either in pure, even-aged stands or mixed with red maple, black gum, sweet bay, and red bay {Persea borbonia) or pond pine {Pinus serotina). The Great Dismal contains three major swamp forest communities in addition to the cedar stands: a. f^aple-Gum, dominated by red maple and black gum, often in association with red bay, sweet bay, sweet gum {Liquidambar styraciflua), and the tulip- tree {Liriodendron tulipifera). Maple-gum now covers 60% of the Great Dismal, having increased significantly in the past 40 years at the expense of both cypress-gum and cedar associations. b. Cypress-Gum, dominated by cypress {Taxodum distichum), tupelo gum {Nyssa aquatica), and black gum. This was formerly the most extensive associa- tion in the swamp. c. Pine, dominated by either loblolly or pond pine. Over time, the composition of the swamp forest varied. In the Great Dismal, the continuing ef- fects of human activities in the swamp now override natural influences on succession. Cedar has been harvested on a large scale in the Dismal Swamp since the 1 8th century when the Dismal Swamp Land Com- pany began operations. Loggers often cut the cedar but left the hardwoods to take over the site, or left so much slash on the ground that cedar seedlings were unable to develop in the resultant shade. Other im- portant factors that have resulted in the gradual suc- cession to hardwoods are suppression of wildfires and changes in the water regime (see Chapter 6). Frost (1 987 and unpubl.) and Ward (unpubl.) discuss Great Dismal commercial cedar logging operations in detail. Despite major disturbances, the swamp still contains typical historical communities whose exist- ence predates the extensive development of the 1940's and 1950's. Many of the historical species in the swamp appear to have survived, but their relative abundance has changed. The five herbaceous species classified as rare or endangered in the cedar wetlands of Virginia (Porter 1 979) all occur exclusive- ly in the Delmarva peninsula. The vascular flora associated with cedar in the Great Dismal, currently consisting of 19 tree, 34 shrub, and 7 herbaceous species (A. Laderman, un- publ.) is included in Appendix A; some frequently encountered species are illustrated in Figure 24. Wildlife on the refuge is discussed in Section 5.3. A list of Great Dismal flora and fauna is maintained by the Refuge staff; the tabulation of 1979-1980 is con- tained in the Refuge Master Plan (USFWS 1986b). Levy and Walker (1 979) examined forest dynamics in the Great Dismal's cedar wetlands. Day and his co- workers have conducted a series of studies on com- munity structure, biomass, productivity, and de- composition rates of a Great Dismal cedar wetland from 1977 to the present (synthesized and sum- marized in Day 1987 and unpubl.). Extensive discus- sions of all aspects of the Great Dismal, including literature reviews, appear in the proceedings of a 1973 conference devoted to the subject (Kirk 1979) as well as in USFWS (1984a and 1986a,b). For fur- ther discussion of flora and fauna of the region, see Chapter 5. Management. Burning, grazing, and log- ging that once maintained parts of the Great Dismal Swamp in different stages of succession or climax were curtailed or eliminated when the Refuge was es- 21 tablished. Drainage from 224 km of ditches and the soil compaction and damming effect of 252 km of roads, exacerbated by accelerating rates of upstream runoff, have seriously lowered the water table in many areas and impounded and flooded others. The net effect has been to progressively replace the distinctive cypress and Atlantic white cedar communities by a relatively uniform red maple- black gum forest. An extensive master plan was developed by the U.S. Fish and Wildlife Service (USFWS 1 986b) in an effort to reverse this trend. Key aspects of the proposed management program (in review at the time of this writing) are outlined in Chap- ter 6. 2.4.2 South Carolina Information on South Carolina cedar wet- lands flora and its distribution was provided by J. Nel- son (pers. comm.) and D.A. Rayner (pers. comm.). Early records of the botanical and logging history of North and South Carolina are described by Frost (1987 and unpubl.)(Figure 14). Radford (1976) lists five counties in South Carolina having populations of white cedar: Lexi- ngton, Kershaw, Chesterfield, Darlington, and Marlboro. Populations are also known from Horry, Georgetown, Richland, and Sumter Counties, and it is very likely that white cedar is also present in Aiken County. All but two of these counties are part of the midlands of South Carolina, where extensive acreages of xeric sandhills are associated with palustrine communities. Francis Marion National Forest contains a few small cedar stands. The South Carolina Heritage Trust data base places Chamaecyparis habitats within the "Atlantic White Cedar Bog" community. All the sites found within sandhill areas are quite similar (J. Nelson, pers. comm.). They always seem to be associated with creek drainages and may extend for several miles near the base of a slope at the creek edge. White cedar forms dense forest at times and sometimes moves onto the sides of the adjacent hills, especially if there is a hardpan of ironstone near the top that for- ces water out along the slopes as intermittent seepages. The water within the sandhill creeks is either clear or tea-colored: its color appears to be re- lated to the size of the stream itself and the distance it has flowed from its headwaters. In very wet areas, abundant Sphagnum is found with lady's slipper {Cyprepedium acaule). cin- namon fern (Osmunda cinnamomea), and sedges (especially fl/?ync/?ospora spp.). Golden club (Oron- tiumaquaticum), tuckahoe {Peltandra virginica), and pitcher plant (Sarracenia rubra) are also found. Shrubs in these bogs usually include fetterbush (Lyonia lucida), gallberries (//ex spp.), blueberries (Vaccinium spp.), titi (Cyrilla racemiflora), and greenbrier (Smilax laurifolia). Vaccinium semper- virens, a low shrub thought to be endemic to some Lexington Carolina bays are a wetland type of un- known origin primarily restricted to North and South Carolina. The bays, dominated by evergreen shrubs, form elongated elliptical depressions on a northwest, southeast axis (Richardson 1981). County drainages, co-occurs with Atlantic white cedar (Rayner and Henderson 1980). Red maple, red bay loblolly bay (Gordonia iasiantlius), sweet bay, and black gum are frequently seen tree species which sometimes occur as large, branched shrubs. Pond pine is occasionally present. In general, these bogs tend to have essentially the same sort of vegetation as many of the pocosin sites in South Carolina, but with a higher and thicker canopy, and perhaps a less diverse shrub layer An unusual white cedar wetland, with a dif- ferent suite of species, is found in Sumter County There is also at least one large Carolina bay in South Carolina (on the bombing range of an Air Force base) containing large white cedars. Carolina bays are a wetland type of unknown origin primarily restricted to North and South Carolina. The bays, dominated by evergreen shrubs, form elongated elliptical depres- sions on a northwest, southeast axis (Richardson 1981). A cross section through a Carolina bay with Cliamaecyparis is shown in Figure 16. 2.5 JUNIPER SWAMPS OF THE SOUTHEAST 2.5.1 Overview Atlantic white cedar reaches its south- ernmost distributional limits in Florida and along the gulf coast of Alabama and Mississippi (Figure 17). The cedar of Mississippi, Alabama, and western Florida differs in some vegetative and reproductive characters from that in eastern Florida and northward. Although controversy surrounds its taxonomy (A. Gholson, pers. comm.; Li 1962), the accepted designation is C. thyoides var henryae (E. Little 1966). Literature on Atlantic white cedar in Florida and along the gulf coast is sparse. Ward (1963) and Collins et al. (1964) briefly described the two southernmost stands of the species, which are both in peninsular Florida. Despite the fact that the largest cedar living today grows in Alabama (see Section 3.2.4), as of this writing scientific literature on Atlantic white cedar in that state is virtually nonex- istent. In 1791, William Bartram described strange cedars growing along the Escam- bia River, noting their similarity to, and differences 22 from, the white cedar of New Jersey. Eleuterius and Jones (1 972) examined white cedar stands in Missis- sippi, at the western edge of its range. A comprehen- sive literature review and a substantial body of hitherto unpublished data on the region's cedar wet- lands were recently gathered by Clewell and Ward (1987) and Ward and Clewell (unpubl.), from which much of the following information is drawn. 2.5.2 Georgia Only two white cedar stands are known in the state, both in west-central Georgia: one grows along a tributary of Upatoi Creek in Talbot and Marion Counties; the other borders Whitewater Creek in taylor County (W. Duncan, pers. comm.). Both stands are on sandy terraces in the east-west belt of Fall Line sandhills along streams that flow southward into the Apalachicola River 2.5.3 Eloiida The southernmost white cedar stand is in northeastern peninsular Florida, along Juniper Creek and its tributary, Morman Branch, in the Ocaia National Forest, Marion County. About 45 km to the north, a second peninsular Florida stand lies along Deep Creek in Putnam County. Both populations flank spring-fed streams that discharge ultimately into the St. Johns River These are the only stands within Florida's Atlantic watershed. All other popula- tions, including those in Georgia, are in the Gulf of Mexico drainage. In the central Florida panhandle, a cluster of cedar stands is associated with streams largely within the watersheds of the Ochlockonee and Apalachicola rivers. Another population center is lo- cated in the western Florida panhandle and Alabama, in association with several streams that inde- pendently flow to the gulf. The westernmost stands lie along several streams in southern Mississippi. In its southern range, white cedar is con- spicuous and often dominant wherever it grows. Paradoxically, populations are often small and iso- lated, even though the cedar's typical habitats are relatively widespread. Autecology. Growth requirements for white cedar in the Florida panhandle generally are similar to those of the Atlantic seaboard provinces, except with regard to hydrology, fire, and pH (Clewell 1971, 1981). White cedar in the south is found where there is little flooding and siltation, on the banks of small t f-i.t j . gjga. AJLiI i I ,ftiiti.Miig. •It roaiST ■MiTtctoM r.'.i Figure 16. Section and plan views of a Carolina bay with Atlantic white cedars, indicating morphological features, soil profiles, and vegetation types. Single arrow points to clump of dead cedars; double arrows point to living cedar forest (modified from Buell 1946). 23 perennial streams (Figure 18) and in tlie back swamps of larger streams, i.e., far from the main channel. Cedars are absent from large-stream flood- plains where alluvial deposits are heavy and seasonal water level fluctuation is great. Atlantic white cedar in peninsular Florida and west along the gulf coast is almost never found in even-aged stands, although it often overtops as- sociated hardwoods and is frequently a dominant component of the canopy The uneven-aged, mixed- species stands typical of the southern white cedar forests are a consequence of gap succession (revegetation under openings in the canopy) in the absence of fire (Clewell and Ward 1987). In contrast to the acid soils in which Chamaecyparis is usually found from North Carolina northward, soil pH of 6.6 to 7.5 has been recorded in Putnam and Marion Counties in peninsular Florida (Collins et al. 1964; Clewell and Ward 1987). Fires are less frequent or at least less destructive than in the northern range of the species, due to the incised topography, the constantly moist soils and leaf litter, and the intermixture of relatively poorly burning vegetation of other species. Clewell and Ward (1987) believe that the relative rarity of de- structive fires in these southern stands favors a mixed forest of white cedar, dicotyledonous hardwood, and sometimes palm, rather than monospecific stands of white cedar. Herbaceous species are often much more numerous than in northern stands. Ward and Clewell (unpubl.) report that lightning, which is particularly frequent in the Florida peninsula, appears to be the major cause of the death of mature cedars there. No white cedars have been reported to survive a lightning strike. MISSISSIPPI ATLANTIC OCEAN Figure 1 7. Atlantic white cedar in Southeastern United States, documented by herbarium specimens and field work. Open circles represent stands of typical C. thyoides; solid circles represent C. thyoides var henryae (modified from Clewell and Ward 1987). 24 2.5.4 Mississippi The following information is drawn from Eleuterius and Jones (1972) unless otherwise noted. The westernmost known extension of Atlan- tic white cedar is a small stand along Juniper Creek near Poplarville in Pearl River County, Mississippi. This mixed stand has been considerably disturbed and was actively logged. The largest stand in the state grows along Bluff Creek in the small community of VanCleave (Jones 1967). Most of the 11.2 km-long stand is below 3 m elevation, with cedars intermixing with pine and hardwood forest at about 6 m. On the south side of the creek, some cedars grew on a steep bluff at 1 8 m elevation. The widest part of the stand was about 0.8 km. Cedars grow on bluffs of various heights, levees, bogs behind the levees, and on gent- ly sloping floodplain areas that end on white cedar covered sand bars. The largest cedar seen was ca. 30 m high and 71 cm in diameter. Betterjg/g 6.7 ±0.4 6.5 ±0.19 B iig/g 40.7 ±3.0 35.3 ±1.1 Al (jg/g 174 ±16 102 ±4.9 Zn ^ig/g 53.5 ±5.9 48.4 ±3.5 Sr pg/g 59.8 ±6.2 30.7 ±1.6 Pb >jg/g 17.8 ±2.9 7.3 ±0.3 Si fvg/g 390 ±18 342 ±10.8 chemistry (Figure 23). The active cation exchange and adsorption capacity of peat (e.g., Gorham 1987), macromolecular aggregates, and Sphagnum mos- ses (e.g. , Clymo 1 963) appear to combine with selec- tive ionic uptake by Chamaecyparis itself to control the water's nutrient content. Measurement of all physical components of cedar wetlands will be useful in clarifying the func- tions that control life in an unusual environment. So little data have been accumulated that virtually every observation would be of both theoretical interest and of utility in management. There are great differences between sites; until more is known, it is inappropriate to extrapolate information from one cedar site to any others. The scant research on the chemical com- position of soils and vegetation of Atlantic white cedar wetlands has not yet produced a clear picture of cause and effect. This is probably due to the intrin- sic complexity of relationships which are further ob- scured by the differing hydrogeological, lithological, biotic, and anthropogenic components of the sites examined. 4.6 INTERACTIONS; RESEARCH NEEDED Other factors not yet measured in cedar wet- lands also probably play roles in the soil and water Cedar wetland soil chemistry appears to dif- fer greatly from its water chemistry. This may provide a clue to the depauperate chemical contents of cedar waters. The soil's active ion exchange, and adsorp- tion processes that remove cations from the water may be part of the mechanism for the accumulation of minerals in Chamaecyparis soil and leaves. 34 [H+] high I Inhibition of Bacterial Action I Organic Material Not Decomposed Undecomposed Sedinnents ( peat) r^^ ++T low, absent [Mg J I Productivity low Low DO ^ LowN.P Available Decomposers Absent in Sediments Colored Water Low Light Penetration Nutrient Absorption Figure 23. Cedar wetland dynamics. Flow diagram indicates proposed interrelationships of physical, chemical and biological properties of Atlantic white cedar wetland waters (modified from Laderman 1980). 35 - CHAPTER 5 - BIOLOGICAL COMPONENTS OF ATLANTIC WHITE CEDAR WETLANDS 5.1 ADAPTATIONS TO THE WETLAND ENVIRON- MENT Plant species growing with the Atlantic white cedar manage to thrive in a waterlogged environ- ment with a varying hydroperiod, and generally acidic, nutrient-poor and often anaerobic soil and water Major physical and physiologic adaptations to this suite of extreme conditions are a hallmark of the biota of the Atlantic white cedar community, but no quantitative work has been published on the sub- ject. Waterlogging and its effects have been exam- ined in bottomland hardwoods (Wharton etal. 1982); physiological adaptation of cells to the acidic milieu is discussed byLevandowsky (1987). Both works in- clude a review of the pertinent literature. 5.2 FLORA 5.2.1 Diversity and Distribution of Associated Species A relatively accurate picture of cedar wet- land biota may be given by consideration of a com- bination of the most constant species (those most frequently co-occurring with Atlantic white cedar); the total species richness (number of species); and those few that are considered rare, endangered, or of other special regional concern. Plants that fre- quently co-occur are termed "constant companions" or "constant species" (Braun-Blanquet 1932; Braun- Blanquet and Pavillard 1930). "Frequency" and "constancy" as used here refer only to the presence of a species in cedar- dominated assemblages and not to abundance of in- dividuals or percent cover. Scientific and common names of all the reported associated vascular flora are recorded in Appendix A. The vertical structure and vegetational com- position of cedar wetlands vary with the age of the stand, the history of natural and anthropogenic dis- turbance, latitude, altitude, the hydrological regime, geomorphology, and microtopography. In some areas (e.g.. New York's Long Island, New Jersey's Hackensack Meadows) many sites are so disturbed that species defined as constant companions of cedars decades ago are now no longer found with cedars, or are themselves near extirpation (see Chapter 2). 5.2.2 Constant Companions Canopy co-dominants. A monospecific, dense, mature, even-aged stand may have a sparse to nonexistent subcanopy, shrub, herb, or reproduc- tion layer, except at breaks in the canopy and at the edges of the stand (by definition, no other tree oc- cupies the canopy). In mixed stands throughout the cedar's range, the most frequently encountered trees are red maple and black gum. Additionally, in the northern states, gray birch {Betula populifolia), black spruce, white pine, and hemlock are most widely distributed. In the mid- dle of the range, sweet bay and a series of oaks {Quercus) and pines (Pinus) supplant most northern species. Further south, bay (Gordonia lasianthus. Persea borbonia, P palustris) and cypress are also frequent canopy or subcanopy associates. Shrub layer. Relatively open-canopy cedar stands generally have a well-developed shrub layer More cedar-associated shrubs are in the heath family (Ericaceae) than in any other The most widely dis- tributed shrubs (including woody vines) associated with Atlantic white cedar are red chokecherry (Aronia arbutifolia), sweet pepperbush, bitter gallberry {Ilex glabra), fetterbush (Leucothoe racemosa), swamp honeysuckle, poison ivy {Toxicodendron radicans), poison sumac (I vernix), and highbush blueberry. Herbaceous layer. The most abundant her- baceous cover is found with cedar on bog mats and as a temporary feature shortly after disturbance that either eliminates the shrub layer or opens the canopy 36 Where there is open water, submerged and emergent aquatics may be present. A continuous carpet of sphagnum mosses (Sphagnum spp.) is often seen wherever there is adequate light. The most widely distributed cedar-as- sociated herbs are: sedges (Carex spp.), round- leaved sundew {Drosera rotundifolia), partridge-berry {Mitchella repens), cinnamon fern, and royal fern (0. regalis). The complexity of dis- tribution patterns and the large numbers of species preclude a simple distribution summary of the shrub and herbaceous layers. The complete geographic distribution of each species is presented in Appendix A. The most frequently encountered associated species are illustrated in Figure 24a, b, & c. 5.2.3 Species of Special Concern Table 6 is an interim list of 89 cedar-as- sociated species and subtaxa (5 trees, 26 shrubs, and 58 herbs) considered as regionally rare, threatened, or endangered. A few plants have recently been removed from some lists of special concern as populations increase or are discovered. Others have been locally extirpated. Individual naturalists, staffs of the Great Dismal Wildlife Refuge and the New Jersey Pinelands Commission, the Na- ture Conservancy, and state Natural Heritage Programs monitor and update these rosters. Further information is presented in Chapter 2 and Appendix A. 5.3 FAUNA Information on animals and associated values is far more limited and spotty than on plants, reflecting the paucity of research in this area. 5.3.1 Wildlife Values Hahilat. A cedar forest managed for maxi- mum wildlife habitat will contain a diverse mixture of old growth, mature, intermediate "pole", and regeneration areas (USFWS 1986b). Maximum variation in vertical stratification is of particular signifi- cance to avifauna (Anderson 1979). The cedar wet- lands can be considered as ecological islands. Large, connected natural areas are of greatest value in promoting wildlife species diversity because there are more species per unit area than in separated is- lands, and there are fewer species lost due to genetic drift (e.g., MacArthur and Wilson 1967; PianlAcer rubrum 2. Magnolia virginiana 3. Nyssa sylvatica var. biflora 4. Pinus elliotti 5. Pinus taeda 6. Taxodium distichum SHRUBS: 7.Clethraalnifolia 8. Cliftonia monophylla 9. Cyrilla racemiflora 10. //ex coriacea 11. Kalmia latifolia 12. Leucothoe axillaris 13. Lyonia lucida 14. Vaccinium corymbosum 40 Table 6. Species of special concern: Flora. An interim list of species that are rare, threatened or endangered in one or more states where they co-occur with Chamaecyparis thyoides. See Appendix A for common names. Sources are listed by state, North to South. Stars (*) denote authorities who provided information and advice on the list for each state; their affiliations are listed in Appendix D. Sources; ME; *BarbaraVickery; Eastman 1978. NH; *Frances Brackley; New Hampshire Natural Heritage Inventory (unpubl.); Storks and Crow [No date]. MA; *Bruce Sorrie and Henry Woolsey; Sorrie 1985. Rl; *Richard Enser: Church and Champlin 1978. CT; *Kenneth Metzler; Connecticut Natural Diversity Database 1985. NY: (Long Island); *John Turner; Mitchell et al. 1980. NJ; *David Snyder; Snyder 1984. MD, DE, VA; *Norman Dill and Arthur Tucker; Broome et al. 1979; Tucker et al. 1979; Porter 1979. NC: *Julie Moore; Sutter et al. 1983. SC: *John Nelson; *Douglas Rayner; Rayner et al. 1979. FL: *Daniel Ward; Ward 1978. Species Location Species Location TREES Larix laricina Rl Magnolia virginiana NY Persea palustris MD Pinus serotina MD Salix floridana FL SHRUBS AInus maritima DE, MD Andromeda glaucophylla Rl, NJ Arceuthobium pusiilum Rl, NJ Callicarpa americana MD Gaultheria hispidula Rl. CT NJ Gaylussaccia dumosa v. bigeloviana Rl Gaylussaccia dumosa v. hirtella SC Gaylussaccia mosieri SC Ilex laevigata ME lllicium parviflorum FL Kalmia cuneata NC, SC Kalmia angustifolia DE Kalmia latJfolia FL Kalmia polifolia Rl Nemopanthus mucronatus Rl Pieris phillyreifolia FL Rhapidopnyllum hystrix FL Rhododendron canadense Rl Rhododendron chapmanii FL Rhododendron maximum MA, CT Smilax laurifolia N J Smilax walterii NJ, MD Symplocos tinctoria MD Taxus floridana FL Vaccinium oxycoccos NJ Vaccinium sempervirens SC HERBS Arethusa bulbosa DE, VA Asclepias rubra NJ Calla palustris Rl Carex collinsii DE, MD Chrysomapauciflosculosa SC Cleistes divaricata NJ Corallorhiza trifida CT Cornus canadensis Rl Cyprepedium acaule Drosera rotundifolia Eleocharis equisetoides Eleocharis robbinsii Epigaea repens triocaulon compressum Eriocaulon parkeri Eriocaulon septangulare Eriophorum tenellum Eupatorium resinosum Helonias bullata Hudsonia ericoides Iris prismatica Juncus caesariensis Liparis loeselii Listera australis Listera cordata Lobelia canbyi Lycopodium inundatum Lycopodium obscurum Myriophyllum humile Nymphoides cordata Cfxypolis rigidior v. ambigua Panicum hemitomon Parnassia grandifolia Peltandra virginica Platanthera ciliaris Potamogeton confervoides Psilocarya nitens Rhynchospora alba Rhynchospora cephalantha Rhynchospora glomerata Rhynchospora knieskernii Sarracenia purpurea ssp. purpurea Schizaea pusilia Scirpus etuberculatus x s. subterminalis Scirpus subterminalis Sclerolepis uniflora Solidago stricta Solidago verna Thelypteris simulata Tofieldia racemosa Utricularia cornuta Utricularia fibrosa Utricularia purpurea Utricularia resupinata Utricularia juncea MD SC DE, MD DE, MD NYSC D^ VA DE, MD MD NJ NJ NJ, DE, VA SC DE, NJ NJ NJ MA NJ Rl SC MD NJ DE NJ FL ME NJ ME, NJ MD VA, SC NJ MD NJ, SC DE, MD NJ SC SC NJ,MD NJ SC DE, MD, VA NJ, SC Rl MD NJ, MD NJ DE, MD ^ Only G. dumosa is recognized in NLSPN (1982) and the USFWS wetland Plant List (Reed 1986). The varieties bigeloviana and hirtella are recognized by local authorities. 41 Table 7. Comparison of bird species observed In a 5.87-ha Atlantic white cedar swamp study piot in Barrington, NH, in 1951 and 1981. Migrants and birds visiting but not nesting in the piot are classed as "seen in piot." Nomenclature follows the American Ornithologists' Union Committee on Classification and Nomenclature (1982). Data from Flaccus (1951) and Miller et al. (1987). Breeding pair§ §e?n in plot Common name Scientific name 1951 1984 1951 1984 Sharp-shinned hawl< Accipiter striatus X Red-shouldered hawl< Buteo lineatus X Ruffed grouse Bonasa umbellus X Biacl<-billed cucl>:>,Ci''l:Y.^X^ elevation and water is ^■^g?10 Steer 1948 1912 1 1914 10 1931 0.02 ca 1940 1 1925-1929 1.87 Brush 1931 Great 1914-1917 >20 Dismal 1921 0.046 ca 1940 5 VA-i-NC 1920-1929 10.73 Brush 1931 NC 1899-1945 2-5 1914-1917 7 ca1940 7 FL 1907 8 Steer 1948 1908-1945 ±0.2 AL 1910 13 1911-1945 0.3-5 FL + AL 1925-1929 2.45 Brush 1931 Summary for NJ, VA, NC, FL, AL 1899-1908 13-20 Steer 1948 1908-1916 20-32 1917-1945 6-14 1925-1929 15.7 Brush 1931 medium sized boats, fencing, decking, and shingles, with smaller quanfrties used for such specialties as lawn furniture and duck decoys. Ward (unpubl.) cal- culated that the 1986 wholesale value of the man- ufactured products was $10 million to $11.5 million annually, with a forest inventory of standing trees of between 170 and 180 million board feet. Annual production is estimated at 19 million board feet (U.S. Forest Service, pers. comm. to D.B. Ward). "Board foot" (bd. ft.) is defined as 1 ft by 1 ft by 1 inch, but the actual thickness is somewhat less. 6.3.1 Large-scale Lumbering Large-scale harvest, as practiced in North Carolina where the great majority of cedar is cut, is done with a gigantic amphibian feller-buncher (Fig- ure 31 ), a machine specifically developed for harvest- ing wetland cedars. The machine's tractor-mounted articulated arms seize the erect tree, shear it at the base and place the cut trees in parallel rows. A man on foot then removes the tops and branches. A skid- der seizes six to eight trees with its rear-mounted grapple and, using the cut tops and branches for traction, pulls the trunks to a roadway. J 54 Table 1 1 . Recent estimates of Atlantic white cedar timber volume. Standing timber >?2 cm diameter Timber removal Location Year million bd ft Year fbd ft/vr^ Source ME -NY 1986 4 (combined with Thuja) A NJ 1971 54 NJ-F 1986 32 1985 900,000 - 1 million NJ-F Delmarva 1986 3 A Great Dismal 1986 40-50 A East NC^ 1985 60 17 million A NC 1984 203 1984 15.321.000 USFS SC 1978 9 1986 4-8 USFS A FL 1980 240 1980 740.000 USFS FL + AL 1986 10-15 1985 400.000 - 600.000 A TOTALS 452 >16 million USFS 170-180 1985 19 million ±500.000 A Total annual value $1 0 million -$11.5 million A All data were collected by D.B. Ward (unpubl.) including that supplied by government sources as indi- cated. Considerable discrepancies exist between estimates of government, industry, and other sources. A: Survey of industry and government (other than U.S. Forest Service [USFS]). NJ-F: New Jersey Bureau of Forestry Management. USFS: U.S. Forest Service unpublished data. ^ Excluding Great Dismal Swamp; majority of trees are 70 years old. In stands of normal density a single operator on a feller-buncher can cut and lay 400 to 500 trees per day. while in the most dense stands this may reach 800 stems per day. The usual rate of cutting is 0.4 ha per day per feller-buncher and support crew (G. Henderson, pers. comm.). Most harvested trees are between 23 and 50 cm diameter; few exceed 60 cm dbh. The feller- buncher cannot handle trunks larger than 1 m in diameter. Such rare trees, missed in the harvests of the early 1900's. may be left standing. This process is most efficient in clear-cutting stands larger than four hectares, with densities of at least 5000 txl. ft., but preferably 10,000 bd. ft., per 0.4 ha (G. Hender- son, pers. comm.). 6.3.2 Regeneration after Harvest G. Henderson (pers. comm.) stated that the greatest natural reproduction is achieved in North Carolina when cutting is done on frozen earth in mid- winter. The feller-buncher clearcut method can allow for healthy regeneration if slash is cleared sufficiently. In one North Carolina site, an abundant cover of fet- terbush {Lyonia lucida) grew with the cedar initially, but cedars overtopped the shrubs by the fourth year By the seventh year an almost solid healthy stand of cedar saplings covered the harvested area (A.D. Laderman and G. Henderson, unpubl. field notes). In other nearby sites where dense slash remained, cedar reproduction was almost nonexistent (J. Moore, J. Taylor, and A.D. Laderman, unpubl. field notes) (Figure 32). Selective cutting of cedar in a mixed stand discourages successful cedar repro- duction (Little 1950). 6.3.3 Influence of Competing Vegetation and Slash Slash left after lumbering severely reduces cedar seedling establishment (Akerman 1923; Korstian and Brush 1931; Little 1950). Cedar see- dlings form dense stands in cleared areas between masses of slash. On logging rollways from which slash was removed. Korstian and Brush (1931 ) found 100,000 to 2 million seedlings per 0.4 ha three years after harvest, and more than 30,000 saplings per 0.4 ha five years later. Few seeds germinate, and fewer survive under the 0.6 to 1 .2 m of dense slash often left after logging (Korstian and Brush 1931). Hardwood 55 sprouts and shade-tolerant shrubs grow out over the slash and are rapidly covered with vines to form a vir- tually impenetrable mass. 6.3.4 Propagation From seed. The USDA recommends pretreatment of cones for extraction of seed (Harris 1974) and placement of seeds in sealed containers if storage is necessary. Stratification (exposure of seeds to a moisture and temperature regimen) is believed to stimulate prompt seed germination, but optimal nursery practice has not yet been defined ex- perimentally for the species (Harris 1 974). Fall plant- ing of seed is recommended in New Jersey (Little 1950). From cuttings. A protocol for propagation by cuttings recommended by T. Dilatush (pers. comm.) follows: Take cuttings in late autumn. Place in a half peat/half sand growing medium, 20 cm deep, over a relatively poor-percolation clay base, in board-sided beds. After 2 years, most seedlings are 30-45 cm. Cut from the bed in 20 cm soil squares. These transplant well into a rototilled sand/peat/clay "veneer" layer of improved soil over relatively imper- vious clay, with periodic sprinkling. Some clones have considerably more rootmass than others. In general, better rooted clones provide more height and girth in a shorter time. Dilatush noted signs of winter stress on the faces of trees along road cuts through monotypic cedar stands following severe winters for many years after the original roadcut. Populations similarly ex- posed in the untouched forest, such as along the river edge face of a monotypic stand, do not appear Figure 31. Amphibious feller-buncher harvesting Atlantic white cedar. Photograph courtesy Atlantic Forest Products, First Colony Farms, Edenton, NC. 56 stressed. Noting that such populations might be preadapted to exposure, Dilatush recommends selection of cuttings from them. 6.4 MANAGEMENT GUIDELINES 6.4.1 Introduction Recommendations for han/est and manage- ment published prior to 1950 were reviewed by Little (1950). The approaches ranged from selective cut- tings of the largest trees (Ashe 1894a), to shelter- wood cutting (where a few seed trees remain) (Pinchot and Ashe 1897), and clearcutting of many dimensions and rotation lengths to produce an even- aged monoculture (e.g., Korstian and Brush 1931; Jemison 1945; Moore 1946). On the basis of extensive field and laboratory observations, Little (1950) proposed an approach to cedar management that has remained the standard for the past three and a half decades. He made it clear that there were (as there still are) too many un- knowns for any simple formula and that each proce- dure should be monitored and assessed for future guidance. Little's recommendations for harvest regimen, management of developing and mixed stands, and restoration follow. 6.4.2 Harvest Regimen a. Manage cedar in even-aged tracts. b. Harvest by clearcutting. c. Remove or reduce slash. d. Control competing hardwoods. e. Control deer browse. f. Cedars should be cut in strips; width of the strips should be determined by stand conditions and the distance of effective seeding (i.e., that which will re- sult in the establishment of several thousand seed- lings per hectare in a 5 - year period). Ideally, har- vested strips should be no wider than 30-45 m. In mixed stands (25 - 50% cedar ), maximum strip width should be 30-60-m. The densest pure cedar stands could be cut in 90 to 120 m strips. g. Delay subsequent harvests in adjacent stands until a 30- to 90-cm well-stocked stand is established. h. The maximum size of a single harvest should be 4 ha. This maximum applies to stands of at least 40 ha. The width of the cutting strips generally dictates the size of the harvested area. i. Control developing hardwood understory. j. Protect from wildfire - possibly by prescribed burn- ing in areas surrounding selected stands. 6.4.3 Management of Developing Stands Silas Little pioneered in his approach to cleaning and thinning. He recommended the as- siduous repeated removals (cleanings) of competing hardwoods - by girdling or chemical treatment - until only pure cedar remained. He also generally op- posed the intermediate harvest (thinning) of young cedar because this practice promoted both cedar windthrow and the development of competing un- derbrush and hardwoods. 6.4.4 Management of mixed stands Recommendations for stands containing less than 50% cedar are more complex and problematical. In stands with 25% to 50% cedar. Lit- tle suggested: a. Clearcut in narrow strips, less than 30-60 m; aim for a maximum number of cedar seed trees on the adjacent windward uncut edge. b. After seedlings on the clearcut reach 0.3-1 m, clearcut another narrow strip. In stands with less than 25% cedar: a. Remove hardwoods and spindling cedars. b. Leave at least 10-20 cedars with good-sized crowns per 0.4 ha. In all cases, removal of slash and repeated cleanings of hardwood are required. 6.4.5 Restoration: Conversion of Hardwood Swamps The establishment of cedar where none cur- rently exists is costly and will be decidedly limited in application. In hardwood swamps, all trees must be felled, girdled, or poisoned; the slash burned; and hardwood sprouts cleaned repeatedly. Further treat- ment may be necessary to prepare a suitable seedbed. Burning or flooding may be useful. Introduction of Atlantic white cedar may be ac- complished by encouraging natural regeneration if seed sources are available, by seeding or planting seedlings. Seeding is preferable to planting of seed- lings in most circumstances. The surface debris un- der a mature dense cedar stand is a good source of cedar seed. Surface debris may be collected and sown from November to May with fair results; 50% germination may be expected (Little 1950). The role of white cedar in reforesting hardwood, non-cedar coniferous, shrub, and other types of wet sites is not yet well defined. 57 w ■; Vk.!-. > A. c. Figure 32. Atlantic wliite cedar regeneration after clearcut harvest of tiiree different narrow cuts adjacent to mixed cedar forests, Dare County, North Carolina. A. Site 1 . One year after harvest. Heavy slash, some shrubs cover open area. Regeneration prospects: poor. B. Site 2. Three to four years post-harvest. Heavy slash, shrubs, deciduous sprouts cover open area. Regeneration: poor to non-existent. C. Site 3. Approximately eight years post-harvest. Slash and shrubs were removed soon after harvest. Regeneration: vigorous, of mixed composition similar to adjacent stands. 58 6.4.6 Fire as a Management Tool United States government guidelines stress prevention and control of wildfire, but controlled burns are an accepted management tool for forest resources (e.g., see memos of U.S. Fish and Wildlife Service, Sept. 14, 1981, April 22, 1982, and April 11, 1983). S. Little, a pioneer in the use of fire as a silvi- culturaltool (Little etal. 1948a; Little etal. 1948b; Little 1953) recommended burning slash during high- water periods shortly after clearcut harvests to promote cedar regeneration. Complete burning is unnecessary: a fire that consumes only dead foliage and fine branches provides suitable conditions for cedar regeneration (Little and Somes 1961). 6.4.7 Cedar Wetlands as Firebreaks The effect of a cedar swamp on a wildfire varies considerably, depending primarily on the depth of the water table, wind orientation in relation to the stand, wind velocity, and the width of the wet- land. The majority of fires recorded in the New Jer- sey Pinelands have been able to breach cedar wetlands narrower than 300 m when impacted by head fires oriented perpendicularly to them. Broader swamps tend to act as firebreaks, especially when the water table is high (Little 1946, 1979; Windisch 1987). 6.4.8 Prediction of Success in Regeneration of a Cedar Stand In a cedar stand completely cleared of higher plants by natural forces or clearcut harvest, the major factors to consider when predicting the potential success of cedar regeneration are the size, shape, orientation, age, condition, prior vegetational composition, and hydrology of the wetland, and the forest type and deer population of the surrounding area (Zampella 1987) (see Figure 33). A large, broad swamp offers protection to the interior from all border influences, both natural (including deer browse) and human. An adjacent mature cedar stand provides a seed source most effectively when it is to the windward. A stand older than 30 years provides the maximum quantity of seed stored in the top peat layer. Dense canopy sup- presses the grov\rth of a heavy shrub layer which would in turn suppress and compete with cedar SIMPLIFIED ATLANTIC WHITE CEDAR MANAGEMENT SCHEME FACTORS TO BE CONSIDERED MANAGEMENT GRADIENT Least Favorat>le Conditions Most Favorable Conditions SIZE Small swamp SHAPE Narrow ORIENTATION Seed source to leeward AGE Less than 30 yrs CONDITION Open canopy /blowdown COMPOSITION Greater than 50% hardwoods HYDROLOGY Dry or flooded ADJACENT FOREST TYPE Hardwood swamp DEER POPULATION High/poor condition PROBABILfTY OF SUCCESSFULLY REESTAB- LISHING WHfTE CEDAR AND MAINTAINING SWAMP SIZE OF HARVEST CUTTING REQUIRED LEVEL OF POST-HARVEST MANAGEMENT SUCH AS SLASH REDUCTION AND CLEANINGS REQUIRED LEVEL OF HARVESTING PRECAUTIONS Large swamp Broad Seed source to windward Greater than 45 yrs Dense canopy Pure cedar stand Saturated soil Upland pine or oak forest Low/good condition Figure 33. Factors that should be considered in planning a harvest are presented along a conceptual management gradient ranging from the least favorable to the most favorable conditions (adapted from Zampella 1987). 59 seedlings; conversely, canopy openings (existing prior to the clearcut) stimulate the growth of preexist- ing shrubs and hardwood saplings. A saturated, but not flooded, hummocky substrate promotes ger- mination and vigorous growth of Atlantic white cedar Adjacent hardwood stands supply competing sour- ces of seed, which necessitates expensive, labor-in- tensive cleanings of hardwood saplings. Cedar swamp would be preferable to any other forest type adjacent to a stand to be cut, for it would serve as a potential cedar seed source and minimize the in- vasion of competing species. 6.4.9 Principles and Objectives With the advice of Silas Little, Zampella (1987), Pinelands Commission scientist, outlined the optimal principles and objectives of cedar manage- ment as follows: a. Public ownership and management is the most effective means of ensuring long-term maintenance. b. Consider maintenance objectives before economic factors. c. Manage for a diverse cedar inventory of all age classes. d. Practice active management (see above) throughout the life cycle of a stand. e. Each entire cedar stand should be considered as a unit for management. f. Convert mixed stands or hardwood swamps to cedar. g. Harvest only when it serves maintenance objec- tives. h. Monitor to assess the effectiveness of methods used. 6.4.10 Implementation: New Jersey Pinelands; Great Dismal The only areas for which cedar management guidelines are proposed or in place are in the State of New Jersey, primarily in the New Jersey Pinelands (described in Section 2.3.1); and the Great Dismal National Wildlife Refuge, Virginia and North Carolina (Section 2.4.1). Pinelands. The New Jersey Pinelands Com- mission (NJPC) incorporates most of Little's (1950) recommendations in its management program (NJPC 1980; Zampella 1987; G. Pierson, pers. comm.), as discussed in Sections 6.4.2 through 6.4.9. The NJPC cooperates with, and is reviewed by, the New Jersey Bureau of Forest Management in supervising timber harvest. It must prepare detailed forestry management plans using management practices that protect site quality and natural re- sources, specifically considering stream crossings, bank protection, soil erosion, tree regeneration, and site treatment during and after harvest (NJPC 1980). Great Dismal. In an effort to reverse the cur- rent trend in the Great Dismal Swamp, in which more mesic red maple and black gum are replacing the dis- tinctive cypress and cedar stands (see Section 2.4.1), the USFWS (1986b) proposed an extensive management program. The most relevant portions of the plan are briefly outlined below. a. Water Management: Implement full water conser- vation to alleviate surface-water loss and ground- water discharge. Hold water in ditches using both temporary and permanent structures. b. Vegetation: Use rotational forest management to emphasize the enhancement of natural diversity and wildlife benefits. Manage Atlantic white cedar on a 100-year rotation (which does not allow for natural stand senescence). Aim to convert about an ad- ditional 1000 ha to cedar over 10 years. A sample of the implementation of the management scheme through the year 2020 is shown in Figure 34. c. Ecological studies: Monitoring will be geared to understanding function and successional dynamics, with priorities as follows: (1) develop a water budget model (2) monitor ground water quality and flow (3) survey understory vegetation to determine suc- cession (4) evaluate value to migratory songbirds (5) monitor effects of resource management pro- gram on songbirds, wood ducks, black bear, deer, and endangered species. The overall plan is to restore the original hydrology as far as possible and to slowly transform the present vegetation community (Figure 35) to one more closely resembling the original swamp. Figures 36 and 37 depict the community projected in 25 and 100 years if it remains unmanaged: in a cen- tury, cedar would virtually disappear, and cypress/gum would be drastically reduced. The en- tire program is flexible, and depends on continual monitoring and evaluation of the efficacy of the ex- perimental management scheme. The complete plan, as well as alternative options and their implica- tions, pertinent legislation, and a bibliography are contained in the Draft EIS of the Master Plan for the Refuge (USFWS 1986b) which is under review at the time of this writing. 60 6.5 THE FEDERAL ROLE 6.5.1 In National Forests Four national forests contain Chamaecyparis thyoides: Croatan in North Carolina, Francis Marion in South Carolina, and Ocala and Apalachicola in Florida. Pursuant to the Forest and Rangeland Renewable Resources Planning Act (RPA) as amended by the National Forest Manage- ment Act (NFMA), the U.S. Forest Service prepared long-range land and resource management plans for the national forests. Morman Branch Botanical Area (Ocala Na- tional Forest) and Mud Swamp/New River Wilder- ness (Apalachicola National Forest) contain about 95% of the Atlantic white cedar in the national forests in Florida. Management direction has not yet been developed for these areas, nor was direction given in the Final Land and Resource Management Plan. 6.5.2 In National Parks Thechargeofthe National Park Service, U.S. Department of Interior, is to preserve and protect their lands while permitting use that does not adver- sely affect the resource. At present, their policy is to use active management only to reverse the effects of human disturbance or to mitigate the impact of natural disasters. The only National Park with Atlantic white cedar is the Cape Cod National Seashore, Orleans, Massachusetts. The swamp, co-dominated in part by red maple, contains cedar of varying ages and sizes with a substantial Sphagnum and herbaceous carpet. A boardwalk cuts through the cedar stand which is maintained for public education and passive recreation. The Service is currently conducting re- search to determine if the area should be actively managed. 6.5.3 In National Wildlife Refuges The major National Wildlife Refuges (NWR) containing Atlantic white cedar are Great Dismal Swamp (GDSNWR) in eastern Virginia and North Carolina (described in Section 2.4.1), and Alligator River NWR in Dare County, North Carolina (to which all of Chapter 7 is devoted). The management plan for GDSNWR is outlined in Section 6.4. 1 0; the current plan for Alligator River does not deal with cedar management (USFWS 1986c). A few small stands grow along streams and below dams in Sandhills NWR, South Carolina (J. Nelson, pers. comm.). Prime Hook Creek NWR, one of Delaware's impor- tant natural areas, also contains at least one small cedar stand (N. Dill, pers. comm.). There are no for- mal management programs for the minor cedar areas. The Refuge system is administered by the U.S. Fish and Wildlife Service. 6.5.4 On State and Private Lands Federal support for private nonindustrial forestry is provided via grants to each state. Funds are available for nursery, wetlands, and forest management; the states are responsible for estab- lishment of good management practice standards. New Jersey is currently the only state that has an active management plan providing for regeneration of Atlantic white cedar (see Section 6.4 [esp. 6.4.10]). The program is in effect on State lands, and in the entire Pinelands National Preserve (G. Pierson, pers. comm.). 6.6 RESEARCH REQUIREMENTS The overall objectives of research needed in the management of Atlantic white cedar wetlands are: 1) to define the biological, chemical, and physi- cal spatial and temporal patterns required for cedar wetland maintenance, restoration, and creation; 2) to determine the most effective designs for restoration and creation of wetland functions; and 3) to develop methods to monitor and evaluate projects aimed at achieving these objectives. Synthesis of existing information and the filling in of gaps in these data provide the framework for the first objective. The development of techniques to support the second and third aims is in its infan- cy and provides an opportunity for cedar wetland workers to make major contributions to the field of freshwater wetland creation and restoration. Brief outlines of selected biological and physical research needs are at the end of Chapters 4 and 5; Chapter 7 ends with requirements pertinent to the Alligator River NWR, many of which are ap- plicable to other sites. The maintenance and revitalization of cedar wetlands are both the opportunity and the imperative for those entrusted with their management. 61 FOREST MANAGEMENT SCHEMATIC LEGEND ■"Forest Compartment Boundary — Study Area Boundary ,;'f Previous Forest Management Activities REGENERATION AREAS: @ Interim Management Hi Prescribed Burning B Convers i on @ Maintenance FOREST MANAGEMENT ACTIVITIES The following sketches depict a possible scheme for forest management in Forest Management Compartment C. Forestry activities over selected target years are shown at a scale of 1 "=94,000'. '^ C.dor ^^^j£^ Evergreen Shrub I 5 I Morsh ^^3 Bog |.......^Edg. I _j Aquat i c Bed Agr I cu 1 ture FOREST AGE CLASS 1 Regenerat ' ve 2 Intermediate 3 Mature 4 Old Age Class Boundory 4^ Ag* cloascs noi OB*igr>«d to r>on-for««l hob i tot SOURCE Grvot Di>a>ol Suonp V«e«iotiv« Cov.r Mop by V-rflimo Cort.r, U S G S and Patricio Goaaon. U S T U S fro* 1978 NASA color lnfror«d photoorophy, and refug* atoff ? ' ° _J KILOMETERS V UNITED STATES DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE SERVICE REGION FIVE Newton Comer, Mossachusetts tprll 1986 Figure 35. Major vegetation community types, Great Dismal Swamp NWR (from USFWS 1986b). 64 GREAT DISMAL SWAhP NATIONAL WILDLIFE REFUGE Virginia and North Carolina VEGETATION COMMUNITIES 25-YEAR PROsJECTION LEGEND Refuge Boundar v Resource Study Area Boundar y State Boundary __ Road/Ditch Corridor HABITAT TYPE ] Mes I c Hardwood I Mop I e-Gum Pine Pt'-W '.''-'.J Cypress-Gum L'Jl^I^J-3 Aquot I c Bed |[J|*9r .culture FOREST AGE CLASS* 1 Regen«rat i ve 2 Intermed i ate 3 Moture 4 Old Age Class Boundory ^ Aq« cloaaes not o»%'gn»d to non-forost hobitot SOURCE R.fuj. Sloff 2 KILOMETERS UNITED STATES DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE SERVICE REGION FIVE Newton Corner, MossQChusetts April 1966 Figure 36. Vegetation community of the Great Dismal Swamp NWR in 25 years, as projected by planners if no management action is taken (from USFWS 1986b). 65 GREAT DISMAL SWAfP NATIONAL WILDLIFE RERJGE Virginia and North Carolina VEGETATION COMMUNITIES: 1 00-YEAR PROJECTION Lgg^Np - Refugs Boundary - Resource Study Areo Boundary - State Boundary - Rood/D I tch Corr i dor HABITAT TYPE [ 1 Me« re Hardwood Map I •-Gum IvM'f^-'^:^ Cypress-Gum §^g^---^ Aquat i c B«d *9r I cu I ture FOREST AGE CLASS* 1 Reg«n«rat i v% 2 Int«rmadiOta 3 Kotur* 4 Old Ag« Class Boundarv ^ A9« claa««« net oas i gn«d to non-for««t habitat SOURCE R.fuo. Staff ^____^_2 MILES I _J KILOnETEBS 1' UNITED STATES DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE SERVICE REGION FIVE Newlon Cofn«r, Massachusetts ifjrll 1986 Figure 37. Vegetation community of the Great Dismal Swamp NWR in 100 years, as projected by planners if no management action is taken (from USFWS 1986b). 66 - CHAPTER 7 - A CASE STUDY: ATLANTIC WHITE CEDAR WETLANDS IN DARE COUNTY, NORTH CAROLINA by Julie H. Moore and Aimlee D. Laderman 7.1 OVERVIEW Mainland Dare County, in northeastern North Carolina, forms a northerly projection at the northeastern end of the low-lying Albemarle-Pamlico Peninsula (Figure 38). It is bounded on the north by Albemarle Sound, on the east by Croatan and Pam- lico Sounds, and on the west by the Alligator River, which is used as a section of the Intracoastal Water- way. The peninsula is separated from the Atlantic Ocean by a string of narrow barrier islands. Except as otherwise noted, data and analyses are previously unpublished field obser- vations gathered by J.H. Moore while working on the USFWS wetlands mapping project and serving as su- pervisor of the Natural Heritage Program Inventory of Dare and Tyrrell Counties (Lynch and Peacock 1982; Peacock and Lynch 1982). 7.1.1 Historical Perspective A century ago, Atlantic white cedar was a common tree of North Carolina's coastal wetlands extending inland to the Fall Line. W.W. Ashe (1 894a), in an inventory of the State's forest resources, es- timated that white cedar, one of the most valuable trees growing in the coastal plain, covered ca. 80,940 ha in North Carolina. By that time, the huge supplies of white cedar in the Dismal Swamp had been har- vested; the most extensive white cedar forests (16,000 ha) were located in North Carolina's Dare, Tyrrell, and Hyde counties. Today, only fragments of the once expansive cedar forests of this area remain. The most extensive white cedar forests extant in North Carolina, and probably in the world, are lo- cated in the Dare County peatlands east of the Al- ligator River, in the Alligator River National Wildlife Refuge. White cedar in this region grows in two types of associations: in distinctive, pure, seemingly even- aged dense stands, and in mixed forests with lowland conifers (cypress, pond and loblolly pine) and hard- woods (black gum [Nyssa sylvatica var biflora], red maple, sweet bay). Black gum in this chapter refers only to the variety biflora, also known locally as swamp black gum. Few old-growth pure stands remain because these forests are the most profitable to harvest. The oldest and largest white cedars in the peatlands occur as scattered individuals about 27 m tall with 0.6 m dbh within the mixed swamp forest association. The habitats supporting these two cedar communities and the species associated with them are essentially the same. Fire and timbering histories appear to be the major factors in de- termining whether a dense, essentially pure white cedar stand develops or a mixed swamp with varying densities of cedar is established (Peacock and Lynch 1982). 7.1.2 Timbering History The history of white cedar harvest in North Carolina is described in detail by Frost (1 987 and un- publ.). McMullan (1 982) provides a comprehensive account of harvest in the Alligator River Region. Major white cedar products in this region were shingles, buckets, cooperage materials, and telegraph and electric light poles (Ashe 1 894a; Frost 67 «' ^a\bemarle sound I HILHNIH, litUMUlH MHV , 1VU4 coMxift HI TMt oivitmi or iim-tv FROM CUHUeVC BV U.R.C.C Figure 38. Alligator River (North Carolina) National Wildlife Refuge including U.S. Air Force Dare County Bombing Range (from USFWS 1986c). 68 1987). Although cedar had been harvested since colonial days in the Alligator River region, it was not until the development of steam-powered logging in the mid-1 800's that large-scale harvesting began. Roper Lumber Company, Richmond Cedar Works, Dare Lumber Company, and many smaller compa- nies operated here between 1865 and 1953. Follow- ing the Civil War, an extensive system of narrow gauge logging railroads opened up previously inac- cessible swamps to intensive harvest. Upon com- pleting a harvest in one area, the rails were moved to another location. As is the practice today, the dense cedar stands were clearcut. Ashe (1 894a) noted that due to access difficulty, white cedar down to the smallest diameter possible (20 cm dbh) was cut. Today, stands with an average diameter of 25 cm dbh are considered the minimum size-class profitable to harvest. From timber cruise estimates, McMullan (1982) calculated that during World War I (1916- 1919), all available cedar was cut by numerous operators on 64,750 ha. Only young hardwoods and some pine pulpwood remained. White cedar timber production was not important again until about 1980 (McMullan 1982). Throughout the period of intensive cedar harvest no attempts were made to encourage natural regeneration, and harvest methods indicate little concern for future timber production. With the ex- ception of a relatively small experiment from 1 960 to 1 970 by Westvaco lumbermen, no efforts were made to reestablish cedar forests following cutting (Mc- Mullan 1982). The intensive harvest of white cedar and the associated swamp species prior to 1920 had a marked effect on the vegetation patterns that exist today. The timbering practices determined regeneration densities and species composition. However, the hydrology of the organic substrate was apparently not substantially altered, for the use of oxen and, later, narrow gauge rails to move timber did not necessitate elaborate permanent road con- struction and ditching. Since the mid-1 970's, Atlantic white cedar has been the species with greatest marketable value in the Alligator River region. An extensive system of roads, ditches, and canals was constructed to pro- vide direct access to the pure, dense stands, par- ticularly in Dare County. The effects of altered local hydrology on white cedar regeneration in Dare Coun- ty have not yet been documented. It is known, how- ever, that a shift towards drier soil conditions tends to prevent the self-maintenance and recovery of the original wetland vegetation types. Today all accessible larger size- class stands in Dare County have been cut once again or are sub- ject to harvest under commercial timber contracts. Pure stands that remain are generally composed of < 23 cm diameter trees that have been growing for up to 70 years. Scattered clumps and indivi- duals of old growth trees still persist in the mixed- swamp forests. 7.1 .3 Alligator River National Wildlife Refuge (ABNWB) In the mid-1 970's, the North Carolina Nature Conservancy initiated discussions about a donation of land (later known as Prulean Farms) on the Dare County mainland to conserve a portion of the region's unique peatlands that had been identified by the North Carolina Natural Heritage Program. Prudential Life Insurance Company purchased the property and, in March 1984, donated 47,755 ha in Dare and Tyrrell Counties to the U.S. Fish and Wildlife Service (see Figure 38). Most of the donated land is on the Dare County mainland, with approximately 2,430 ha in Tyrrell County west of the Alligator River. Timber rights to Atlantic white cedar stands on these lands are reserved until 1996 by Atlantic Forest Products, a subsidiary of the Canadian lumber firm, McMillan Bloedell, Inc. All timber rights have been subcontracted to the Alligator Timber Company. The area was designated as the Alligator River National Wildlife Refuge. In 1 986, a draft 20-year master plan (USFWS 1986c) for the management of the Refuge was prepared, and is under review at the time of this writing. Within the boundaries of the Refuge is the 18,867 ha U.S. Air Force Dare County Military Reser- vation (Figure 38), which consists of a 2,470 ha bombing range surrounded by 16,390 ha of buffer lands. The Westvaco lumber company retained mineral rights, and Atlantic Forests Products retained rights (later subcontracted to Alligator Timber) to har- vest tracts of white cedar until 1 989 (USFWS 1 985b). The North Carolina Natural Heritage Pro- gram initiated discussions with the U.S. Air Force in 1983, recommending measures for the preservation of extensive natural areas. In 1986 negotiations culminated with the registry by the North Carolina Department of Natural Resources and Community Development (NCDNRCD) of 7,690 ha as protected N.C. Natural Heritage Areas. Over 4,045 ha are high-quality cedar swamp forest contiguous with swamps of the Refuge, containing both pure and mixed white cedar associations. These Natural Areas will be managed by the U.S. Air Force for their natural values, with tim- ber rights leased as noted above (USFWS 1985; Registry Agreement on file with NCDNRCD 1986). 69 7.2 PHYSICAL CHARACTERISTICS 7.2.1 Geology Mainland Dare County is located on the Pamlico Terrace and bordered by water on three sides with a land connection to the south. The penin- sula is based on recent Quarternary deposits con- sisting of surficial organic materials of varying thickness overlying undifferentiated and complexly interbedded layers of sand, silt, clay, and mollusk shells (Heath 1975). The following discussion of recent geo- logical processes follows Peacock and Lynch (1982). The Pamlico Terrace is the lowest and youngest of the several generalized surfaces of the Coastal Plain recognized as having been formed during periods of higher sea level. About 75,000 years B.R, the edge of the sea lay inland to a point now marked by the sandy ridge of the Suffolk Scarp (Daniel 1981) lo- cated 72 km to the west of the Dare mainland's cur- rent shoreline. At the peak of the Wisconsin glaciation, the sea was far below its modern level. As elsewhere in the cedar's range, the complex cycle of marine transgressions and regressions produced differing effects upon the topography of the al- ternately exposed and submerged surfaces. Rising seas slowed stream erosion by raising stream base levels, and planed off the previous surface features or obscured them with silts and muds. Falling sea level, in contrast, exposed areas of the continental shelf and rejuvenated streams, increasing downcut- ting and topographic relief. 7.2.2 Development of Peat Deposits During the recent period of rising sea level, conditions favorable to peat formation have prevailed in Dare County and throughout the North Carolina Coastal Plain. During the past 1 0,000 years, peat has been forming under swamp forests, pocosins, and marshes, in blocked drainages, Carolina bays, and river floodplains (Otte 1981). Ex- tensive sampling of peat depths, in conjunction with surveys of energy-grade peat deposits, indicate the presence of a subpeat system of southeast to northwest oriented stream channels (Ingram and Otte 1981, 1982) which have not yet been explored in detail. 7.2.3 Soils Soils of mainland Dare County were mapped for the first time by Barnes (1981, and unpubl.; USACE 1982) (Figure 39). Organic soils predominate; the deepest histosols border the Al- ligator River and also occupy prepeat drainage chan- nels in the interior of the county. Shallow histosols generally adjoin deeper peats in the soilscape; mineral series occur in areas which were interstream divides, slightly more elevated on the prepeat sur- face. Prepeat topography is now thoroughly ob- scured by organic deposits, as illustrated in Figure 22, where a cross section shows the relationships of peat depth, underlying mineral sediments, and soil series. In Dare County, Atlantic white cedar associa- tions are most frequently established on deep or- ganic soils of the Dare and Pungo Series or on the shallower histosols of the Ponzer, Kilkenny and Mat- tamuskeet series. Pure and mixed stands are occa- sionally associated with the Roper and Pettigrew series which are mineral soils with a histic epipedon (organic surface layer). In a few instances (e.g., west of the northern half of the bombing range), swamps including white cedar are found extending from or- ganic soils onto poorly drained mineral soils which have a thick black or very dark gray highly organic loam surface (Hyde and Cape Fear soil series). All of the soils of the region, classified as "hydric soils" by the Soils Conservation Service (USDA, SCS 1985a), are extremely wet year round, though water seldom pools on the surface. They are acidic (pH 3.0-4.0) (Barnes, unpubl.) and have large quantities of Atlantic white cedar and bald cypress roots, stumps, and logs throughout the profile. Sur- face and subsurface accumulations of charcoal indi- cate a history of severe fires in parts of the region (Otte 1981). The transition zone between organic and mineral material averages less than 0.5 m, with little soil development in the underlying mineral layer (Dol- man and Buol 1967). Daniels etal. (1984) believe that the lack of a distinct soil beneath the histosols indi- cates that the soils of the region have been con- tinuously wet, with buildup of organic materials during wetter periods and loss during drier climatic times. Soils suitable for white cedar establishment appear to be abundant in many areas of the Dare peninsula, principally concentrated in the western sector closest to the Alligator River 7.2.4 Physiography and Hydrology The Dare mainland lies within the Atlantic Coastal Plain Physiographic Province and is charac- terized by relatively flat terrain with elevations rang- ing from 3.7 to 0 m above mean sea level, declining 70 gradually from west to east. As a consequence, the black-water stream systems that drain the peninsula are relatively short and slow-flowing. The development of extensive Atlantic white cedar wetlands on the western sector of the Dare Peninsula, rather than to the east where pocosin vegetation dominates, appears to be related to the historic and contemporary flooding of the region rather than to depth of peat, soil series, or fire history, since the latter parameters are quite similar in both sections (Peacock and Lynch 1982). The complex interactions of organic soils, water flow, and de- velopment of the distinctive nonalluvial swamp forests of the peatlands, as condensed from Peacock and Lynch (1982), follow. LEGEND ^ Pump Simon H Marsh & Flood KHl Arsas m Dirk & Hiitic Min«rBl Soils Shallow Organic Soil) u D«tp Organic Soil* _ Proiaci Units Milnary Rasarvaiion SCALE: 1 ||CI= 3 IILES 1 Figure 39. General soil types of mainland Dare County (from USAGE 1982). 71 The cedar swamp forests along the Alligator River are nonalluvial in the sense that the Alligator is an estuary or embayed stream that neither transports a heavy sediment load nor has frequent high over- bank flows. The mainland Dare swamp forests are physiognomically and hydrologically distinct from swamps of brown-water river flood plains; however, they appear to be more similar to those distant riverine swamps than to the nearby pocosins (see Section 7.3, esp. Section 7.3.4). Pocosins and pure and mixed cedar forests are found on a similar range of peat depths. Charcoal layers sandwiched within forest peat profiles indicate that fire has occurred in such swamps without subse- quent pocosin development (Otte 1981). Otte con- cludes that water-flow patterns are the major difference between cedar swamp forest and pocosin sites. In these swamp forests, the water flow is pri- marily into and through the systems; in nearby areas supporting pocosins, the major flow is out of the sys- tem. A large amount of Dare County cedar swamp water comes in from surrounding high ground or through flowing streams that carry clay and dis- solved nutrients, whereas the major source of pocosin water is precipitation. Consequently, the peat that supports swamp forests has a higher average mineral content than does peat underlying pocosins (Otte 1981). The flat terrain, combined with the high evapotranspiration rate of the dense vegetation and the low hydraulic conductivity of the organic soils of undisturbed cedar wetlands, causes water to move very slowly, predominantly overland, and through the root/litter mat (Skaggs et al. 1980; USFWS, unpubl. b). Historically, drainage patterns would have been overland to stream systems and thence into the nearest river or sound. However, the peninsula has been altered by highway and canal construction resulting in rapid drainage pathways generally less than 1.6 km long (USAGE 1982). The pattern of hydrological change is very similar to that of the Great Dismal (see Section 2.4.1), but the alterations are not as drastic. 7.2.5 Climate The Albemarle-Pamlico peninsula has a temperate climate with warm summers and mild winters. Winter temperatures seldom fall below -12 °G and summer temperatures often exceed 32 °G in July and August; humidity is usually high. The freeze-free season in mainland Dare County is 1 80 to 220 days long (USAGE 1982). Precipitation averages from 1 14 to 137 cm per year, with peaks generally occurring July as a consequence of sum- mer thunderstorm activity. Fall is usually the season of minimum rainfall. Annual amounts may be as low as 89 cm during dry years and as high as 203 during unusually wet years (USAGE 1982). Because the Dare peninsula is surrounded by water, it is subjected to a strong coastal sea breeze regime. Prevailing winds are from the south-southwest, with average speeds of 14 to 17 km/hr (Copeiand et al. 1983; USAGE 1982). 7.2.6 Tidal Influence The Dare peninsula is largely protected from the influence of lunar tides by the coastal barrier is- lands to the east, although dampened lunar tides of small magnitude do occur Wind-generated tides are the principal source of water-level fluctuation within sounds, the Alligator River, and Milltail Creek. In the river and creek, rising tides usually result from west- northwest through east-southeast winds with falling tides usually resulting from southwest through west- southwest winds. Mainland Dare is subject to tidal in- undation only under extreme conditions, and zones of flood-killed vegetation border the sounds where this has occurred (USAGE 1982). 7.3 VEGETATION 7.3.1 Introduction Atlantic white cedar associations, par- ticularly the dense, monospecific stands, have inter- ested North Carolina botanists and ecologists for sometime (Ashe 1894a, b; Korstian 1924; Wells 1932; Buell and Cain 1943). However, it was not until the early 1 980's, when attention was focused on pocosin and peatland losses, that any descriptive material or quantitative data on the vast coastal cedar peatlands was gathered. Natural area studies for mainland Dare, Hyde, and Tyrrell Counties (McDonald and Ash 1981; Peacock and Lynch 1982; and Lynch and Peacock 1982) are the principal published sources of information on white cedar associations of the peat- land region. Unpublished substantiating data has been provided by intensive vegetation sampling by the USFWS Ecological Services Office. Wetland mapping for Dare County as a part of the National Wetlands Inventory project (USFWS, progress reports) has provided additional information. Macrofossils in the peat profile indicate that white cedar has long been a component of the mixed swamp forests that dominate the western half of the Dare mainland (Otte 1981). The role that spon- taneous fires, lightning, saltwater flooding, and hurri- cane windthrow played in originally opening habitat for white cedar colonization is completely obscured by the area's history of extensive timbering. The 72 white cedar stands upstream from Milltail Lake, to the southeast of Sawyer Lake, and to the north and southeast of Whipping Creek Lake are the only ones on the Dare peninsula that are associated with streams or bodies of water. The largest monospecific cedar stands of the region are relatively young. Generally they date from the period of intense timber harvest that ended before 1920; most of the stands that regenerated ear- lier than the 1 920's have been harvested again or are under contract to be cut. The majority of the acces- sible pure stands are composed of trees 23 cm or less in diameter; stands with an average diameter of less than 25 cm are not economical to harvest today. If they are within 425 m of a road, pure stands as small as 4 ha are economical to harvest (G. Henderson, pers. comm.). Remnants of older age-class stands occasionally border clear-cuts. The largest and oldest white cedars in Dare County are found in ma- ture non-alluvial swamp forests, where they co- dominate the canopy with the lowland conifers bald cypress, loblolly pine, and pond pine. Black gum is the most important hardwood species of this as- sociation in terms of frequency and percent cover Individual cedars range from 46 to 69 cm in diameter and from 24 to 27 m in height. At many sites, majestic straight-trunked cedars tower above the surrounding mixed hardwood/conifer swamp forest. Recent establishment of the dense cedar stands here, as in other parts of the species' range, has commonly followed removal of competing vegetation by clearcutting of similar stands or of mixed swamp forest. The type of hydric soil, whether a deep or shallow histosol or mineral soil, does not appear to be a major limiting factor to cedar estab- lishment in western mainland Dare County. The hydrological patterns adjacent to the Alligator River seem to affect the development of swamp versus pocosin vegetation, rather than pure versus mixed cedar associations. Though old growth canopy specimens predominate, subcanopy and juvenile cedar are also present in the mixed swamp forest (Peacock and Lynch 1982; USFWS 1982; S.W. Leonard and J. Moore, unpubl. field notes). Comparison of white cedar wetlands on the Dare mainland as mapped using 1976 aerial photography (USAGE 1982) with those mapped in 1984 by the National Wetlands in- ventory (USFWS, progress reports) reveal the exten- sive harvest that occurred during that period (Figure 40). Cedar continues to be cut under long-term tim- ber contracts. 7.3.2 Wetlands Classification Wetland mapping has been completed for mainland Dare County through a cooperative effort between the National Wetlands Inventory (USFWS) and the North Carolina Department of Natural Resources and Community Development. All cedar associations in the Dare region are classified as palustrine wetlands with a saturated moisture regime (Cowardin et al. 1979; and see Sec- tion 1 .2). Water is at or near the surface during most of the growing season, but since standing water is not necessarily present, the wetland character of the cedar forests is not always evident. Although some cedar stands do not occur over deep organic soils, the National Wetlands I nven- tory maps use the descriptive symbol "g" (indicating an organic substrate) to separate cedar forests from other wetlands dominated by needle-leaved trees. On the wetlands map, pure and mixed cedar associa- tions as well as the variable canopy composition of mixed associations are reflected in the symbols which indicate the estimated ratio of evergreen to deciduous needle-leaved trees (bald cypress), or to deciduous hardwoods and occasionally, evergreen broad-leaved trees (e.g., loblolly bay [Gordonia lasianthus] or sweet t)ay [Magnolia virginiana]). 7.3.3 Pure Stands The dense, pure white cedar stands of ail age classes are characterized by a distinctive ground-surface layer made up of a jumble of fresh and partly decomposed cedar trunks and intertwined greenbrier {Smilax spp.). Access into the stands is difficult; seemingly solid substrate may collapse under full body weight. Surface water is only occa- sionally evident, though the soil is almost constantly saturated. Where the density of trees is lower, the ground surface is less cluttered and more level, and shallow pools of water are present. A low diversity of associated species is characteristic. Few to no canopy or subcanopy trees interrupt the continuous dark-green cedar foliage. Black gum and, infre- quently, red maple extend into the canopy but are more commonly a part of the subcanopy along with red bay, which varies greatly within and between stands both in height and density. Where the canopy is not completely closed, red bay may form a dense subcanopy above an evergreen shrub layer; oc- casionally it is within the shrub layer (Peacock and Lynch 1982). Generally the density of the shrub layer is determined by the maturity of the canopy, being most dense and impenetrable in the youngest stands. The shrub species present most consistently are fetterbush (Lyonia lucida), highbush blueberry 73 Alligator River LEGEND Pure Atlantic while cedar starxls Mixed Atlantic wtiite cedar tiardwood swamp forest Pure stands harvested twtween 1976 and 1982 Transect Areas SCALE N MLES SCALE IN KILOMETERS Figure 40. Atlantic white cedar wetlands of mainland Dare County, status in 1976 and in 1984, from aerial mapping (see text). 74 (Vaccinium corymbosum), and bitter gallberry (Ilex glabra). The herbaceous layer is consistently depauperate. Sphagnum spp. are found sporadical- ly in patches where water stands on the surface. Mats of partridge berry {Mitchella repens) oc- casionally cover stumps and fallen logs. Vegetation analysis. Sampling of six cedar stands by line intercept (Canfieid 1941) and quarter point (Cottam and Curtis 1956) methods in 1982 by theUSFWS(unpubl.) provides the only quantitative vegetation data available to date on Dare County white cedar (Table 12). Study sites are indicated on Figure 40. The average cedar dbh for six sites ranged from 13.7 to 32.5 cm. The largest diameter- class stand was harvested soon after sampling. Canopy cover of white cedar ranged from 40% to 86%; cover contributed by additional species in the canopy and subcanopy ranged from 13% to 77%. Unpublished quarter point data delineating the character of each site is on file with the Office of Ecological Services, USFWS, Raleigh, NC. In the largest size-class sampled (stand #041; dbh aver 32.5 cm), white cedar contributed 81 % of the cover. The four other species recorded in the canopy or subcanopy were black gum, red maple, pine, loblolly bay, and red bay. White cedar diameters ranged from 15 to 53 cm, the average being 32.5. The multiple subcanopy and shrub layers dominated by evergreen red bay and fetter- bush under a tall canopy of white cedar was consis- tent with observations by Peacock and Lynch (1982) and by other wetland biologists mapping in stands of harvestable size. 7.3.4 Mixed forests Pooled or shallow standing water is often present on the surface of mixed cedar stands. The proportion of white cedar in the mixed lowland con- ifer and hardwood swamps varies greatly. The har- vest of certain species, particularly bald cypress and cedar, has determined in part what species are dominant today. The high proportion of lowland con- ifers and the abundance of evergreen shrubs make the physiognomy of these forests distinctly different from that of the forest dominated by black gum and/or cypress in flood plains of brown-water river systems. The principal canopy species occur here in proportions varying from site to site, with black gum the dominant hardwood present. Either white cedar or loblolly pine may be codominant. The amount of cover contributed by these species is more variable than that provided by black gum. White cedar is found throughout the mature swamp forest stands as majestic, straight-trunked, small crowned old- growth trees. Individual cedars range from 46 to over 61 cm dbh. Loblolly pine is more scattered, but often attains comparable diameters and usually exceeds cedar in height. Emerging from the canopy at many sites are scattered old-growth bald cypress left by loggers as cull trees. Bald cypress was probably a more significant component of the Alligator River swamps before selective timbering. Several other species reach the canopy, but are of far less impor- tance than the principal species. Red maple is locally dominant where cypress, cedar, and black gum have been removed or thinned by logging. Pond pine and isolated large sweet bay are occasionally found in the canopy. Table 12. Vegetation cover Summary of line-intercept data from six Atlantic white cedar stands in Dare County, North Carolina showing the variations in cover ratios and sizes of cedar. From USFWS, unpublished HEP analysis data (1982). Stand Ave-DBH # white cedar (cm) Total % cover white cedar Total % cover other canopy-subcanopy species^ Total % cover shrub species^ Total % cover herb species^ Soil series 036 13.7 50 77 125 7 Pungo 051 15.7 76 13 160 106 Pungo & Belhaven 037 16.5 40 77 172 22 Pungo 055 20.6 51 55 179 0 Pettigrew 040 21.3 86 18 120 7 Belhaven &PetligBA/ 041 32.5 81 36 166 71 Pungo Percent cover may exceed 100% due to the presence of overlapping vegetative strata. 75 Generally, the mixed swamp forest sub- canopy is not well developed, consisting of smaller individuals of black gum and red maple with an oc- casional sweet bay. The shrub layer is rather open and generally consists of one or two species. A tali layer of red bay is frequently present, ranging from tall shrub to subcanopy height. The dominant low shrubs are usually sweet pepperbush and fetterbush, with scattered gallberry and highbush blueberry. Fetterbush is less dense in mixed swamps than in dense cedar stands. Ground cover is usually absent except for Sphagnum mats. The ground surface may be wet, with shallow standing water in scattered depressions. Cypress knees and many fallen logs add to the hummocky surface; however, the ground surface of mixed swamp forests is more open than that of pure cedar stands. No quantitative data are available on mixed stands in which cedar is a codominant species. However, unpublished field notes of L. Peacock and M. Lynch (pers. comm.) describe several such sites. At a site near Milltail Creek Lake, white cedar and cypress form a closed canopy 21 to 27 m tall over a second canopy of black gum with some red maple and red bay about 12 m tall. Common shrubs recorded are sweet pepperbush, fetterbush, and bit- ter gallberry. Rotting stumps of cut cypress are com- mon. Another mixed stand to the north, considered representative, contains white cedar 21 to 24 m tall with an average dbh range of 36 to 40 cm. The co- dominant hardwood component consists of black gum and red maple. Widely scattered hollow, old- growth cypress protrude from the cedar-hardwood canopy. Sweet bay, red bay, and red maple com- pose the subcanopy. Peacock and Lynch (1982) noted that sweet gallberry is more common at this site than elsewhere. Other shrubs they noted were fetterbush, maleberry {Lyonla ligustrina), bitter gallberry, and blueberry. 7.3.5 Unusual or Rare Plant Species To date, no rare plant species have been found within the Atlantic white cedar associations of the Dare mainland. The highly acidic and con- tinuously saturated character of the substrate, coupled with dense shade from the overstory and shrub layers, limits the potential for a diversity of all low-growing plants, as well as for unusual or rare ones. The few herbaceous species that have been found within Dare cedar forests are listed in Table 1 3. 7.4 FAUNA The fauna of mainland Dare County palustrine wetlands has been investigated only in response to the major land alteration proposals of Table 13. Plant species characteristically as- sociated with Atlantic white cedar wetlands in Dare County, North Carolina. Canopy and subcanopy layer Acer rubrum Gordonia lasianthus Magnolia virginiana Nyssa sylvatica var. biflora Persea borbonia Pinus serotina Pinus taeda Taxodium distichum Shrub layer Amelanchier candensis Clethra ainifolia Cyrilla racemiflora Gaylussacia frondosa Ilex coriacea Ilex glabra Ilex opaca Leucothoe racemosa Lyonla ligustrina Lyonia lucida Myrica cerifera Myrica heterophylla Smilax laurifolia Smilax rotundifolia Smilax walteri Vaccinium fuscatum Viburum nudum Herbaceous layer Mitchella repens Osmunda regalis Parthenocissus quinquefolia Peltandra virginica Rhus toxicodendron Sphagnum sp. Wooawardia areolata Woodwardia virginica the past few years. Until recently, limited road access to the interior of the peninsula and inhospitable con- ditions have been major factors contributing to the basic lack of understanding of the dynamics of these unusual wetland habitats. A detailed summary of existing data on the fauna of the Dare mainland was prepared by the USFWS (Noffsinger et al. 1984) in a Fish and Wildlife Coordination Act report. The only additional source of information for the area is from Clark etal. (1985). The studies of Potter (1 982a, b) ; Braswell and Wiley (1982); and Peacock and Lynch (1982), com- bining data on the fauna of both pure and mixed cedar forests in Dare County, catalogue 24 mam- malian, 4 herptile, and 52 resident and breeding bird species (Appendix B and Table 14). The southeastern five-lined skink, ground skink, and slimy salamander (Braswell and Wiley 1982), and carpenter frogs (Peacock and Lynch 1982) are the only herptiles thus far documented in various undisturbed cedar associations. Only six 76 Table 14. Summer birds of mainland Dare County North Carolina white cedar habitats. Data sour- ces for habitat: L = Lynch (pers. comm.); PL = Peacock and Lynch (1982); P = Potter (1982a). Status codes: PR = Permanent resident; SR = Summer resident; PV = Permanent visitor (non- breeding); * = non-breeding in this habitat. Species Habitat Pure Cedar IVIixed Cedar/Hardwood Status PL SR PL,P PR P SR PL,P PR P PL,P PR PL PR PL,P SR L PL PR P PR PL,P PR PL,P SR* L PL SR PL PV* PL.P PR L PL,P PR PL,P PR PL,P PR P PL,P PR P SR PL,P SR P PL,P SR PL SR PL PR L PL PR L L PR P PL,P PR PL,P PR PL PR PL,P PR L PL SR PL,P SR PL,P PR PL,P SR PL,P SR PL,P PL.P SR PL.F PL,P SR L PL SR P PL,P PR P PL,P SR P SR P PL,P SR PL PL,P SR PL,P SR PL,P SR P PL,P PR PL,P SR PL.P PR P SR PL.P PR PL PR L PL PR PL PR Green iieron Wood ducl< Osprey Red-shouldered hawl< Bobwhite Mourning dove Yellow-billed cucl