Cedar Swamp Research Articles

An Analysis of Atlantic White Cedar (Chamaecyparis thyoides (L.) B.S.P.) Tree Rings as Indicators of Ghost Forest Development in a Globally Threatened Ecosystem

Atlantic White Cedar (AWC) swamps are a globally threatened type of wetland ecosystem and are a new form of ghost forest in the mid-Atlantic region of the US. Hydrogeomorphic regimes foster peat formation, resulting in unique biodiversity and carbon sequestration services. Our sites include regimes that are exposed to sea-level rise and storm-driven seawater intrusion, yet other sites are protected by higher elevations. In this study, we evaluated climatic variables to discern differences in tree ring formation as an indicator of growth among nine stands including micro-tidal, oligohaline sites as well as other protected areas which served as a control. Standard dendrochronological techniques were used, and series were divided into two sub-chronologies, 1895 to 1971 (early) and 1972 to 2018 (recent). AWC growth in response to precipitation parameters, e.g., Palmer Drought Severity Index (PDSI), were largely non-significant but were somewhat reversed among sub-chronologies. Early correlations were primarily negatively correlated with PDSI, while recent correlations were mostly positive, which suggests that even though inundation may reduce photosynthate availability for growth, precipitation has begun to increase growth by alleviating osmotic and toxic stresses associated with seawater. Analysis of climatic variables and tree growth at the reference site found that other anthropogenic stressors associated with ditching exert a greater influence. Hurricane impacts on tree growth exhibited no lasting negative effects; however, an AWC ghost forest report from New Jersey connected mortality to a hurricane. Hydrogeomorphic regimes may delay rather than eliminate risks associated with sea-level rise and storm-driven seawater.

Groundwater Controls on Wetland Vegetation of a Ridge-and-Swale Chronosequence in a Lake Michigan Embayment

A chronosequence of wetland swales between beach ridges in the Manistique/Thompson embayments of Lake Michigan contains plant communities that differ across the strandplain. We characterized vegetation in 33 swales and compared distribution with previously reported groundwater flow systems. Older swales near a groundwater divide created by the peak Nipissing ridge receive local flows and hold sedge/leatherleaf floating mats that transition to swamp. Farther lakeward, another groundwater divide is created by discharge of calcareous waters released by termination of an underlying clay confining layer, resulting in swales dominated by northern white cedar. Cedar swamp continues lakeward in swales having flow-through calcareous groundwater, but several swales are perched above those flows. Farther lakeward, a large amalgamated beach ridge creates another groundwater divide with discharges that again support cedar swamp. Calcareous discharge from the confined aquifer, with downslope flow-through waters, then supports more cedar swamp. Flow-through waters meet yet another calcareous discharge, resulting in ponding and development of floating mats. Finally, a deep regional aquifer discharges at the Lake Michigan shore and supports marsh/shoreline species. Our results have implications for assessing potential responses to climate change, interpretation of past climate changes in paleoecological studies, and management of wetlands facing future climate changes.

Rainfall partitioning through a mixed cedar swamp and associated C and N fluxes in Southern Ontario, Canada

AbstractPartitioning of rainfall through a forest canopy into throughfall, stemflow, and canopy interception is a critical process in the water cycle, and the contact of precipitation with vegetated surfaces leads to increased delivery of solutes to the forest floor. This study investigates the rainfall partitioning over a growing season through a temperate, riparian, mixed coniferous‐deciduous cedar swamp, an ecosystem not well studied with respect to this process. Seasonal throughfall, stemflow, and interception were 69.2%, 1.5%, and 29.3% of recorded above‐canopy precipitation, respectively. Event throughfall ranged from a low of 31.5 ± 6.8% for a small 0.8‐mm event to a high of 82.9 ± 2.4% for a large 42.7‐mm event. Rain fluxes of at least 8 mm were needed to generate stemflow from all instrumented trees. Most trees had funnelling ratios <1.0, with an exponential decrease in funnelling ratio with increasing tree size. Despite this, stand‐scale funnelling ratios averaged 2.81 ± 1.73, indicating equivalent depth of water delivered across the swamp floor by stemflow was greater than incident precipitation. Throughfall dissolved organic carbon (DOC) and total dissolved nitrogen (TDN) averaged 26.60 ± 2.96 and 2.02 ± 0.16 mg L−1, respectively, which were ~11 and three times above‐canopy rain levels. Stemflow DOC averaged 73.33 ± 7.43 mg L−1, 35 times higher than precipitation, and TDN was 4.45 ± 0.56 mg L−1, 7.5 times higher than rain. Stemflow DOC concentration was highest from Populus balsamifera and TDN greatest from Thuja occidentalis trees. Although total below‐canopy flux of TDN increased with increasing event size, DOC flux was greatest for events 20–30 mm, suggesting a canopy storage threshold of DOC was readily diluted. In addition to documenting rainfall partitioning in a novel ecosystem, this study demonstrates the excess carbon and nitrogen delivered to riparian swamps, suggesting the assimilative capacity of these zones may be underestimated.

Status of Appalachian Jacob's-Ladder in Vermont

abstract Nine Element Occurrences (EOs) of Appalachian Jacob's-ladder Polemonium van-bruntiae in Vermont were recognized in 2002. Presently there are 15 EOs comprising 79 Sub-Element Occurrences (subEOs). The author monitored all 79 subEOs at least once and 31 of them twice between 2004 and 2017. The total number of sexually reproductive stems was 32,300, averaging 2153 per EO and 409 per subEO. Six subEOs had fewer than 10 plants each. More than half the subEOs occurred in wooded seeps; the remainder occurred in wet meadows, alder thickets, northern white cedar swamps or human-altered patchy habitats that mimic seeps. In Vermont the species is currently known only from southeast Addison County. The species is now more populous but only slightly more widely distributed in Vermont than in Deller's account. Increase in numbers is due to discovery of new EOs and subEOs, as well as to population growth of the EOs known since 2002. It remains at risk to the same variety of threats that it was believed subject ...

Using metagenomics to show the efficacy of forest restoration in the New Jersey Pine Barrens.

The Franklin Parker Preserve within the New Jersey Pine Barrens contains 5000 acres of wetlands habitat, including old-growth Atlantic white cedar (or AWC; Chamaecyparis thyoides) swamps, cranberry bogs, and former cranberry bogs undergoing restoration into AWC forests. This study showed that the C-use efficiency was greater in the old-growth AWC soils than in soils from 8-year-old mid-stage restored AWC stands, which were greater than found in soil from 4-year-old AWC stands-the latter two stands being restored from long-term cranberry bogs. A metagenomic analysis of eDNA extracted from these soils showed that the C-cycle trends were associated with increases in the relative numbers of DNA sequences from several copiotrophic bacterial groups (Bacteroidetes and Proteobacteria), complex C-decomposing fungal groups (Sordiomycetes, Mortierellales, and Thelephorales), and collembolan and formicid invertebrates. All groups are indicators of successionally more advanced soils, and critical for soil C-cycle activities. These data suggest that the restoration activities studied are enhancing critical guilds of soil biota, and increasing C-use efficiency in the soils of restored habitats, and that the use of metagenomic analysis of soil eDNA can be used in the development of assessment models for soil recovery of wetlands following restoration.

Square-stalked St. John’s-wort, <i>Hypericum tetrapterum</i>, in Peel Region, Ontario: a New Non-native Vascular Plant Species for Eastern North America

The Eurasian Square-stalked St. John’s-wort (Hypericum tetrapterum Fr.: Hypericaceae) was found growing in an open Eastern White Cedar (Thuja occidentalis L.) swamp in Caledon, Regional Municipality of Peel, Ontario. This is the first record for eastern North America; previous North American occurrences have been on the Pacific coast in Vancouver, British Columbia, Canada (1991), and in Wahkiakum County, Washington State, USA (2003).

Aboveground Forest Biomass and Litter Production Patterns in Atlantic White Cedar Swamps of Differing Hydroperiods

Ecosystems dominated by Chamaecyparis thyoides (Atlantic White Cedar) are critically endangered due to hydrologic alterations associated with ditching, logging, development, and agricultural conversion. Few studies have related structural and functional characteristics of this plant community to water tables, yet hydrologic management options may be critical to establish a peat-based seed refugium and allow Atlantic White Cedar self-maintenance in this ecosystem. In this study, we assessed aboveground forest biomass, litter production, and depth to water table at a mature (60–70 y) and an intermediate (20–35 y) age-class stand in two national wildlife refuges, Alligator River (AR) and Great Dismal Swamp (DS) in North Carolina. We calculated forest biomass from morphometric data gathered within randomized study plots. We made monthly litter collections at each study plot from November 1998 to April 2000; litter was sorted by species and type for the first 12 months. Wells installed at each study plot recorded water-table levels, which were at or near the surface at AR but >30 cm below the soil surface at DS throughout the study. Although Atlantic White Cedar was a dominant species at all sites, community structure differed between refuges. Total aboveground biomass was similar among age classes; however, Atlantic White Cedar stem density was greater and mean diameter at breast height was lower at AR. Mean annual litter production was higher at AR sites for each age class despite a persistently high water table. We conclude that the rates of primary production associated with high water tables at AR represent favorable conditions for Atlantic White Cedar self-maintenance.

Homoacetogenesis: A potentially underappreciated carbon pathway in peatlands

Due to anaerobic conditions, peatland soils store globally significant amounts of carbon and are an important source of methane, a potent greenhouse gas. One component of anaerobic carbon cycling, homoacetogenesis (i.e., acetate formation from carbon dioxide and dihydrogen via the acetyl-CoA pathway), has rarely been quantified in natural environments because it is commonly viewed as being thermodynamically unfavorable. Here we show that in a laboratory incubation using a tracer method, homoacetogenesis occurred at significant rates in soils from three peatlands (bog, intermediate fen, and cedar swamp) despite thermodynamic conditions that appeared to be unfavorable for this process. Homoacetogens consumed dihydrogen at rates up to 3- to 10-times faster than methanogens, and homoacetogenesis accounted for 16–63% of total acetate production, with the balance likely coming from fermentation processes. Our results show that homoacetogenesis can play an important role in regulating acetate dynamics, methane production, and carbon cycling in peatlands.

Beaver pond effects on carbon storage in soils

Beaver ponds have been shown to be hot spots of carbon trace gas flux, which begs the question, “What is the source of the carbon?” The density and stratigraphy of carbon storage was studied in soils of boreal beaver meadows, graminoid wetlands that develop after a beaver pond is abandoned and drained, at Voyageurs National Park on the U.S.–Canada border, where beaver re-colonized the landscape during the latter half of the 20th century. Carbon density was measured to a depth of 60cm by collecting volumetric samples in mineral soils from the side walls of hand-dug trenches and in a Histosol using a box corer. Interpretation of pre-beaver (1940) aerial imagery showed the presence of cedar swamps in locations that currently have Haplosaprists and Argiaquolls, with deep carbon storage that cannot be attributed to recent beaver activity. Excluding these sites, carbon density to a depth of 60cm was still significantly greater in beaver meadow pedons (15.1±6.8kgm−2) than in adjacent forest soils that had not been impounded (8.2±2.9kgm−2). The difference was attributed to the accumulation of graminoid plant debris in thick surface O horizons. Volumetric carbon concentrations were greatest in O horizons, and a linear regression between O horizon thickness and carbon density was significant. Parent material origin (i.e., glacio-fluvial vs. glacio-lacustrine) did not significantly affect carbon density. This research confirms the presence of soil carbon adequate to supply trace gas fluxes, but suggests that considerable carbon is sequestered by beaver impoundments in the meadow stage, which may offset carbon release that occurs during the pond stage.

Hiding Out at the Pancake Palace by Nan Marino (review)

Reviewed by: Hiding Out at the Pancake Palace by Nan Marino Karen Coats, Reviewer Marino, Nan Hiding Out at the Pancake Palace. Roaring Brook, 2013 [256p] ISBN 978-1-59643-753-1 $16.99 Reviewed from galleys Ad Gr. 4–6 Eleven-year-old Elvis Ruby is a phenomenal talent: he can play just about any musical instrument, sing like an angel, ooze charisma, and oh, that hair! He’s a shoo-in to win TweenStar, the reality show/performance competition, or at least he was until he froze on stage and immediately had to go into hiding at a family friend’s pancake restaurant in a small New Jersey town. Cecelia Wreel, a resident of that small town, couldn’t be more different from Elvis: she’s an unpopular, unmusical small-town girl (though she thinks she might like music if she could hear the song that her mother and father insist was playing through the pines on the night she was born in a cedar swamp in New Jersey). When Elvis shows up at her local pancake place disguised as a nondescript boy named Aaron, she sees him as a potential friend, but when she overhears him whispering his real name to the pines one night, she imagines that he, if anyone, can help her find her song. The infusion of the folkloric tropes of singing pines and the Jersey Devil adds a not-meant-to-be-subtle metaphor for the problems that beset the two; both are on the cusp of adolescence and searching for their identities in mostly the wrong places by trying to live up to the ideals of those around them. Threaded through the book are wisps of other themes, such as the power of music, the importance of maintaining tradition weighed against staying current, and the difficulty of keeping secrets. While these individual melodies are sweetly played, the book never becomes a harmonic whole, with abrupt shifts between subplots that readers will need to synthesize without much authorial assistance. It’s really the premise that takes center stage anyway: Elvis himself is a stand-in for an actual young pop star [End Page 472] with real talent and swoon-inducing hair, and the story of his going into hiding among regular folk will have wish-fulfillment appeal for many a young reader. Copyright © 2013 The Board of Trustees of the University of Illinois

Stenanthium leimanthoides(Melanthiaceae) andNestronia umbellula(Santalaceae) in Alabama

Stenanthium leimanthoides (A. Gray) Zomlefer & Judd, commonly known as pine barren deathcamas, is classified in the Melanthiaceae family and is a former member of the polyphyletic genus Zigadenus (Zomlefer and Judd 2002). It is spottily distributed from New York and New Jersey south through West Virginia to North Carolina and Tennessee. It also appears in the Gulf Coastal Plain, where it is a rare taxon ranging from west central Georgia (Carter et al. 2009) to south Alabama, northwest Florida (Anderson 1995), south Mississippi, and southeast Louisiana, perhaps extending as far west as east Texas (USDA Plants Database 2012). Plants in the Gulf Coastal Plain are generally very robust, sometimes attaining heights of two meters or more. Flowering in the latter region is mostly from May through the middle of June, and plants typically have paniculate inflorescences in which each branch (raceme) is elongate and tight. Habitats of Stenanthium leimanthoides range from Atlantic white cedar and bay swamps in Georgia and Florida, to cutover shrub bogs and seepage slopes in other southeastern states, including Alabama. Pine barren deathcamas is listed as an S1 taxon by the Alabama Natural Heritage Program (2011) in Auburn. Species with this ranking are considered critically imperiled due to extreme rarity. While conducting fieldwork in late May of 2008 in the coastal plain of southeastern Alabama (frequently referred to as the Wiregrass Region), a new population of Stenanthium leimanthoides was discovered. Plants were at peak anthesis in southwestern Barbour County, Alabama (Figure 1). This site is approximately 95 km southeast of Montgomery and is in the Southern Red Hills physiographic region and the Choctawhatchee–Pea River Watershed. Pine barren deathcamas plants had paniculate inflorescences (Figure 2) and were robust, with heights of up to two meters. The habitat for the newly discovered population of S. leimanthoides is a seepage slope along a power line in a highway right-ofway cut through a creek swamp with Magnolia virginiana L., Liriodendron tulipifera L., Nyssa biflora Walter, and Persea palustris (Raf.) Sarg. A collection was made using standard herbarium techniques and was deposited in The University of Georgia Herbarium (GA) and the Troy University Herbarium (TROY). Table 1 has a listing of vascular plant species associated with S. leimanthoides at the Barbour County site. Nomenclature primarily follows Weakley (2011). Standardized abbreviations for authorities were obtained from The International Plant Names Index (2012). To learn more about the distribution and ecology of Stenanthium leimanthoides in Alabama, curators of the following herbaria were consulted: University of Alabama (UNA), Auburn University (AUA), Jacksonville State University (JSU), University of North Alabama (UNAF), University of South Alabama (USAM), Troy University (TROY), University of West Alabama, the Anniston Museum of Natural History, and Vanderbilt University (VDB) housed at the Botanical Research Institute of Texas (BRIT). Relevant specimens were directly examined at AUA, JSU, and TROY. The Alabama plant atlas (Kral et al. 2012) was accessed to verify the distribution of pine barren deathcamas in other regions of the state. Additional data on the distribution and habitats of this species were provided by the Alabama Natural Heritage Program in *email address: mwmorris@troy.edu Received June 8, 2011; Accepted September 11, 2012. DOI: 10.2179/12-016

The A.D. 900-930 Seattle-Fault-Zone Earthquake with a Wider Coseismic Rupture Patch and Postseismic Submergence: Inferences from New Sedimentary Evidence

Stratigraphic evidence for coseismic uplift, a tsunami, and a sandy debris flow linked to the A.D. 900–930 Seattle‐fault‐zone earthquake and subsequent submergence is present at Gorst at the terminus of Sinclair Inlet, Washington. This study indicates that at least 3 m of uplift preceded a tsunami followed by a sandy debris flow. Though the Seattle and Tacoma fault zones ruptured within the error of ages of the tsunami deposit, model simulations indicate the Seattle fault generates an order of magnitude larger tsunami in the vicinity of the field area than the Tacoma fault and is the more likely generator of the tsunami. Simulations indicate amplitude from a Seattle‐fault‐zone‐generated wave train was 4–5 m, and stratigraphy shows the tsunami left a sandy deposit. Soft‐sediment deformation narrows the time window for the debris flow to the hours to months after the tsunami. Slope failure in unconsolidated glacial sands likely initiated a debris flow that surged at least 2 km down Gorst Creek valley and left a more than 40‐cm‐thick deposit along the creek and in the wetlands. Submergence of a Thuja plicata (western red cedar) swamp into the intertidal zone indicates at least 1.5 m of submergence in the last 1100 years. This submergence indicates uplift on nearby marine terraces associated with the Seattle fault zone was likely higher, and the A.D. 900–930 earthquake was potentially larger, than previously recognized.

Patterns of Nitrogen Mineralization in Wetlands of the New Jersey Pinelands along a Shallow Water Table Gradient

Abstract Nitrogen dynamics in wetlands are often assumed to vary with water tables and the resulting patterns of soil moisture, and other soil properties. To test this hypothesis, we have examined N mineralization patterns in two replicate sequences of three forested wetland types located on a shallow water table gradient in the New Jersey Pinelands during a 12 mo sampling period. Each sequence of the three forested wetlands consists of pine wetlands and pine-hardwood swamps with sandy mineral soils and cedar swamps with peat soils along the shallow water table gradient. Although water tables differed between the two mineral-soil wetlands, there were no differences in soil properties between them, including patterns of extractable N or net N mineralization rate. However, peat soils from the cedar swamps had net N mineralization rate 5–10 times higher than the mineral soils from the other two types of wetlands over the sampling period. Although soil moisture was correlated with water table position within ...

Landscape Scale Modeling of the Potential Effect of Groundwater-level Declines on Forested Wetlands in the New Jersey Pinelands

The objective of the study, which is a component of a comprehensive evaluation of the hydrologic and ecological effects of groundwater pumping from the Kirkwood-Cohansey aquifer, was to apply empirically determined hydrology-vegetation models to develop geographic information system (GIS)-based landscape models for three study basins in the New Jersey Pinelands. The wetland- indicator modeling suggests that the area dominated by wetland species will decline in area with increased groundwater withdrawal due to the predicted drop in water table. While some patterns revealed in the results are reasonably consistent across basins, other changes are a function of the unique topographic form and hydrologic characteristics of a particular basin. The results suggest that cedar and hardwood swamps which are at the wetter end of the water table gradient will show the greatest percent declines in area. The landscape modeling suggests that at the higher levels of groundwater withdrawal the decline of wetland area will be especially severe in the upper headwaters of the basins, and that there will be ‘retreat’ of existing wetlands to a narrower streamside corridor. The landscape modeling also suggests that there will be a change in the broader landscape pattern with a simplification of the wetland mosaic with fewer patches.

Development of Vegetation Models to Predict the Potential Effect of Groundwater Withdrawals on Forested Wetlands

We developed vegetation models that, when linked to groundwater-hydrology models and landscape-level applications, can be used to predict the potential effect of groundwater-level declines on the distribution of wetland-forest communities, individual wetland species, and wetland-indicator groups. An upland-to-wetland vegetation gradient, comprising 201 forest plots located in five different study basins and classified as either upland pine-oak, pitch pine lowland, pine-hardwood lowland, hardwood swamp, or cedar swamp, paralleled variations in water-level. Water levels, woody-species composition, the percentage of wetland- and upland-indicator species, and soil properties varied among the five vegetation types. Because of the functional relationship of hydrology with its correlated soil variables, hydrology represented a good proxy for the complex hydrologic-edaphic gradient associated with the upland-to-wetland vegetation gradient. Two types of vegetation models were developed to predict potential changes in vegetation associated with water-level declines. Logistic regression models predicted the probability of encountering the different vegetation types and 29 community-indicator species in relation to water level. Simple regression models predicted the relative abundance and richness of wetland-and upland-indicator species as a function of water level.

Occurrences of the LiverwortFrullania selwynianain the Superior National Forest, Minnesota: Overlooked or Recovered?

Frullania selwyniana Pearson was historically recorded from only two localities in Minnesota, and was last seen in 1925. The species became listed on the Region 9 Sensitive Species List (USDA Forest Service 2007) as it is a North American endemic and rare throughout its range. We recorded it in 2001 on the Superior National Forest during a Forest-wide baseline bryophyte inventory. During a dedicated survey in 2008 throughout the Superior National Forest and adjacent areas we have now located 165 populations within 19 widely separated forested stands. Most of the sites are within highly paludified white cedar swamps (i.e., with significant Sphagnum cover). However, several records are from cedar trees in ecotones between upland and lowland cedar mesohabitat, or in mixed hardwood-conifer or shrub-conifer swamps. It appears that the patches tend to be found on the upward-facing bark of leaning trees, usually directed toward some canopy opening. In addition to being overlooked inland from the shore, it has apparently recovered quite dramatically from its earlier restricted occurrence of nearly a hundred years ago. Most likely this is related to the recovery and aging of white cedar stands after restrictions to earlier logging practices went into effect.

The effects of changes in soil moisture on nitrogen cycling in acid wetland types of the New Jersey Pinelands (USA)

Wetlands are subject to changes in soil moisture as a result of both short-term seasonal climate variations and long-term changes in regional water resource management, both of which can modify the dynamics of ground and surface water inputs. In the New Jersey Pinelands, forested wetlands that differ in both plant communities and soil structure occur along a topographic and hydrological gradient associated with an unconfined aquifer. Proposed groundwater withdrawals may affect water content of soils along this gradient. We hypothesized that prolonged changes in soil moisture would alter net nitrogen mineralization and nitrification rates in proportion to the amount of moisture change, and that these changes would be similar for the different soils along the drainage catena. Soils from two catenary sequences of wetlands, including pine-dominated (driest landscape position), hardwood-dominated, and Atlantic white-cedar-dominated (wettest landscape position) communities were used in long-term laboratory incubations (36 weeks). Production of NH 4 +–N, NO 3 −–N, and dissolved organic N were measured under two sets of conditions: constant moisture levels of 100%, 60% and 30% water-holding capacity (WHC), and fluctuating moisture levels (alternating 2 week periods at 100% and 30% WHC). In soils from most of the wetlands, we observed increases in net mineralization and nitrification when constant low-moisture conditions were established, but not under fluctuating conditions. Contrary to expectations, responses to the drying treatments varied between wetland types and between replicate wetlands of each type. Under constant-moisture conditions, nitrification increased more in cedar swamps than in either type of pine wetland. Under all conditions, soils from all the wetlands within one of the catenas produced more inorganic and organic soluble N than did the wetlands from the other catena, suggesting that area-wide effects are as important as wetland type in regulating production of soluble N. Within both catenas, pine-hardwood wetlands generated more soluble N under all moisture conditions than did either pine-dominated or cedar wetlands. Our results suggest that changes in soil moisture due to management of water resources will affect N cycling in wetland soils, but that the magnitude of the effects, and the potential for large releases of nitrate, will depend on the specific soil properties of affected wetlands.

Stream and wetland landscape patterns in watersheds with different cranberry agriculture histories, southern New Jersey, USA

Stream and wetland-landscape patterns in watersheds that drain active-cranberry bogs, abandoned-cranberry bogs, and forest land with no history of cranberry agriculture were compared at three different levels of detail. Stream-pattern variables included drainage density, sinuosity, and the number, density, and length of ditches. Landscape-pattern measures included wetland-patch structure (the size, shape, and number of wetland patches) and cover-type composition. The results of the stream-pattern analysis indicated that the effect of past and present cranberry agriculture on stream-drainage patterns was limited primarily to the occurrence of ditches. A greater number, density, median length, and total length of ditches were observed in cranberry and abandoned-bog basins compared to forest basins. Drainage density and sinuosity of the remaining non-ditched stream segments did not differ between basin types. Excluding areas of active-cranberry bogs where the native vegetation was removed, there was no significant difference in the relative number, size, shape, and composition of the remaining vegetation-cover types between the three basin types. The exact type and extent of vegetation removed to establish bogs in the active and abandoned basins are not known, but based on soil type and vegetation class associations, it was estimated that the largest losses were of pitch pine lowlands and cedar swamps.

Distribution and ecology of Lecanora conizaeoides (Lecanoraceae) in eastern Massachusetts

In its native Europe, the lichen Lecanora conizaeoides is an obligate acidophile: it always grows on substrates with a low pH. Its notorious, rapid spread through Europe in the 20th century followed an increase in atmospheric sulfur dioxide pollution that artificially acidified many substrates on which this lichen would normally never occur. During the last 50 years, this species has appeared in several scattered, coastal North American sites. In 2000, a new population was discovered in an Atlantic white cedar swamp in eastern Massachusetts; subsequently, three additional rural populations, as well as three suburban populations, have been found in the area. Specimens from these seven populations are morphologically and chemically indistinguishable from other North American and European specimens. Substrate pH measurements reveal that, with one exception, all substrates colonized by L. conizaeoides in eastern Massachusetts are highly acidic (pH < 4), thus demonstrating that this lichen is behaving as an acidophile, just as it does in Europe. At the four rural sites, L. conizaeoides displays an almost singular affinity for Atlantic white cedar (Chamaecyparis thyoides), growing on its wood and, less frequently, its bark. But at the three suburban sites, this lichen colonizes the bark of various tree species, most of which give pH values noticeably lower than at the rural sites. The acidification of these tree species at the suburban sites cannot be explained by high concentrations of atmospheric sulfur dioxide, however, because these concentrations have never approached the levels recorded in Europe during the spread of this lichen there. All our observations suggest that, in eastern Massachusetts, L. conizaeoides established itself first in rural Atlantic white cedar swamps, and is subsequently spreading to other, suburban sites which contain sufficiently acidic substrates. This pattern of invasion is strikingly similar to that hypothesized for Europe by Wirth (1985), who suggested that L. conizaeoides originated in Pinus mugo bogs, from which it gradually expanded into more urbanized areas.

Mushrooms of Cape Cod and the National Seashore

Although known for its sandy beaches and pounding surf, historic Cape Cod is also home to a unique community of mushrooms that can be found on its heaths, pine and oak barrens, and on the borders of its bogs, kettle ponds, and cedar swamps. Here is the definitive guide to the highly varied mycoflora of Cape Cod and the National Seashore. It contains accurate and up-to-date descriptions and over 150 color illustrations that help the reader identify over 250 indigenous mushroom species. The scope of this work goes well beyond the identification of mushrooms. The authors provide information that increases the readers awareness of the fragile nature of Cape Cod's various ecosystems and the critical role that mushrooms play in helping to preserve them.