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Potential Disconnect Between Observations of Hydrophytic Vegetation, Wetland Hydrology Indicators, and Hydric Soils in Unique Pitcher Plant Bog Habitats of the Southern Gulf Coast
Jacob F. Berkowitz, Sanderson Page, and Chris V. Noble

Southeastern Naturalist, Volume 13, Issue 4 (2014): 721–734

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Southeastern Naturalist 721 J.F. Berkowitz, S.Page, and C.V. Noble 22001144 SOUTHEASTERN NATURALIST 1V3o(4l.) :1732,1 N–7o3. 44 Potential Disconnect Between Observations of Hydrophytic Vegetation, Wetland Hydrology Indicators, and Hydric Soils in Unique Pitcher Plant Bog Habitats of the Southern Gulf Coast Jacob F. Berkowitz1,*, Sanderson Page2, and Chris V. Noble1 Abstract - The Sarracenia spp. (pitcher plant) bogs located along the southern Gulf of Mexico represent a unique natural resource characterized by endangered and endemic wetland floral communities that include a number of carnivorous plants (e.g., pitcher plants and Drosera spp. [sundews]). Despite the prevalence of obligate wetland plant species and indicators of wetland hydrology, the soils underlying this niche ecosystem often lack clear indicators of hydric soil morphology, posing challenges to wetland delineation and resource management. The National Technical Committee for Hydric Soils and an interagency team of soil scientists investigated saturated conditions and anaerobic soil conditions in pitcher plant bogs. Our results demonstrate that many of the pitcher plant-bog soils examined failed to meet an approved hydric soil indicator. Herein, we discuss potential factors preventing the formation of typical hydric soil morphologies including: low organic-matter content, high iron-concentrations, extensive bioturbation, presence of high-chroma minerals (e.g., chert), and short saturation-intervals. Our examination of soil morphology and condition in these unique and ecologically valuable habitats indicates that additional studies are required to address the apparent disconnect between observations of soils, hydrophytic vegetation, and indicators of wetland hydrology to ensure the appropriate management of these endemic natural resources. Introduction The lower Gulf Coastal Plain of Alabama, Florida, Louisiana, and Mississippi contains Sarracenia spp. (pitcher plant) bogs, including communities referred to as wet Pinus spp. (pine) savannahs, Fallicambarus spp. (crawfish) flats, pine flatwood, pitcher plant prairie, and grass–sedge bog (FNAI 1990, Wharton 1978). Multiple carnivorous plant species, including pitcher plants and Drosera spp. (sundews) consistently occur in these ecosystems (Fig. 1a; Smith 1988). Under natural conditions, sparse overstory canopies of Pinus palustris Mill. (Longleaf Pine) and/or Pinus elliotti Engelm. (Slash Pine) underlain by a diverse community of forbs and grasses characterize these areas. Many species of orchids, lilies, and grasses (some rare, endangered, and endemic) are only found in this ecological niche (Folkerts 1977). The natural ecology of bog communities remains extremely sensitive to disturbance brought about by soil manipulation, fire suppression, and alteration of the hydrology (Harper et al. 1998). In the absence of fire, pines and large shrubs encroach on these areas, resulting in changes to species diversity and a build-up of biomass and 1US Army Corps of Engineer Research and Development Center, Vicksburg, MS 39180. 2US Department of Agriculture Natural Resources Conservation Service, Loxey, AL 36551. *Corresponding author - Jacob.F.Berkowitz@usace.army.mil. Manuscript Editor: Julia Cherry Southeastern Naturalist J.F. Berkowitz, S.Page, and C.V. Noble 2014 Vol. 13, No. 4 722 Figure 1. a) Sarracenia leucophylla (White-topped Pitcher Plants) flourish after a recent prescribed burn, b) typical landscape setting within the study area, c) deep and d) shallow soil profiles. Note that surface layers exhibit high chroma (≥3) but contain many redoximorphic features common to hydric soils. Subsurface layers are characterized by prominent iron concentrations and the accumulation of clay capable of supporting a high water table and hydrophytic vegetation. Southeastern Naturalist 723 J.F. Berkowitz, S.Page, and C.V. Noble 2014 Vol. 13, No. 4 fuel (Brewer 1999). Increased fuel loads often result in less frequent but extremely hot, ecologically damaging fires (Frost et al. 1998, Huffman and Blanchard 1990). Additionally, increased rates of bioturbation are reported in the study area, with densely occurring crawfish burrows observed at many pitcher plant bogs (Folkerts 1990). Pitcher plant bogs are often underlain by clay materials at depths less than 50 cm (20 in), a feature that impedes drainage and promotes perched high water tables and the development of wetland hydrology (Folkerts 1991, Schafale and Weakley 1990). Many soils in pitcher plant bogs remain highly weathered and very acidic (Plummer 1963, Wells 1971), and fire regimes impact nutrient abundance and availability (Mckee 1982). Pitcher plant-bog ecosystems are widely distributed across certain parts of the landscape (Fig. 2a). Soil scientists and federal agency personnel reported that many soil pedons in pitcher plant bogs lack a hydric soil field-indicator when the hydrology and hydrophytic plant community indicate wetland conditions. For example, two soil series (Tibbie and Pinebarren) established in Washington County, AL, appear to meet wetland hydrology and hydrophytic vegetation criteria, but often fail to display characteristic hydric soil morphology (USDA-NRCS 2013) exhibiting high chroma (i.e., ≥3) within near-surface layers (Fig. 1). In this study, we present the results of investigations of the lack of hydric soil field-indicators, through Figure 2. a) Potential pitcher plant-bog communities of southwest Washington County, AL, projected on a hillshade reflief map. Soil-map units are: AtA–Atmore fine sandy loam, 0–2 percent slopes; AtC–Atmore fine sandy loam, 2–8 percent slopes; and TPB–Tibbie and Pinebarren soils, 1–5 percent slopes. b) Site locations relative to geologic surface-units on a composite map. The Sandhill Crane Refuge study area occurs on a young Holocene/Quaternary terrace (Qc) near the contact with the Pliocene Citronelle formation. The Washington County study area occurs on the Tertiary Miocene (Tm), and Splinter Hill Bog occurs near a contact of the Citronelle Formation and the underlying Miocene, undifferentiated unit (Tm). Southeastern Naturalist J.F. Berkowitz, S.Page, and C.V. Noble 2014 Vol. 13, No. 4 724 application of the hydric soil technical standard (NTCHS 2007), in pitcher plant bogs and discuss potential causes of the observed soil morphology and barriers to hydric soil indicator expression. Study Sites and Methods The National Technical Committee for Hydric Soils (NTCHS) retains the responsibility for establishing field indicators of hydric soils in the US (Vasilas et al. 2010). During 2011, local US Army Corps of Engineers (USACE) personnel and Natural Resources Conservation Service (NRCS) soil scientists identified the issue of high chroma soils in pitcher plant bogs and requested that NTCHS conduct a study and field visit to the affected area. As a result, local soil scientists identified 3 areas for investigation (Fig. 2b). The Mississippi Sandhill Crane National Wildlife Refuge study area in Jackson County, MS, is located in land resource region (LRR) P, near the contact of the major land resource areas (MLRA) 133A and 152A—Southern Coastal Plain and Eastern Gulf Coast Flatwoods, respectively (USDA-NRCS 2006). This site is 6 m (20 feet) above sea level on a relatively young (Holocene/Quaternary) marine terrace. The area occupies a low-lying, nearly level terrace drained by Taxodium (cypress)/Liquidambar (gum) swamps. Hydrology of the terrace (recharge area) and the swamps (discharge area) is governed by the nearby Pascagoula River (USDA-NRCS 2013). Rainfall, the nearly level topography, and low relief govern local site hydrology. The Washington County study area is located near the town of Tibbie, AL, and The Nature Conservancy’s Splinter Hill Bog study area is in Baldwin County, AL; both occur at elevations above 60 m (200 feet) and exhibit open drainage systems. The sites feature older, more dissected landscapes, situated within MLRA 133A. Hydrologic periodicity remains complex because of the number of tributaries that contribute to subsurface and surface-water movement (USDAS-NRCS 2013). Onsite hydrology is governed by stream-order complexity, the impermeable substratum, landscape position, and topography. The sites occur on nearly level to gently sloping flow-through and discharge areas on foot slopes and toe slopes. As seen in Figure 2a, the pitcher plant bogs examined occur in close proximity to the established Atmore series: coarse-loamy, siliceous, semiactive, thermic Plinthic Paleaquults; the newly documented Tibbie series: fine-loamy, mixed, semiactive, thermic Plinthaquic Paleudults; and the newly documented Pinebarren series: coarse-loamy, siliceous, semiactive, thermic Plinthaquic Paleudults. We identified two sample points at each location and completed soil descriptions according to the regional supplement to the USACE wetland delineation manual (Wakeley et al. 2010). We excavated all soil profiles using a spade until we reached a restrictive clay aquitard. In addition, at all sites, we installed instrumentation necessary for applying the hydric soil technical standard (HSTS; NTCHS 2007). The HSTS requires data to 1) establish that soils display anaerobic conditions, and 2) demonstrate adequate saturated conditions during the growing season. We tested for the presence of anaerobic conditions using indicator of reduction in soils (IRIS) Southeastern Naturalist 725 J.F. Berkowitz, S.Page, and C.V. Noble 2014 Vol. 13, No. 4 tubes based on the methods of Rabenhorst and Burch (2006) and Berkowitz (2009). We installed triplicate IRIS tubes at each sample location and if 2 out of 3 IRIS tubes displayed 30% iron removal within a 15-cm (6-inch) zone, we considered that the criteria for anaerobic conditions criteria set by the HSTS had been met. We evaluated removal of Fe from IRIS tubes by using scanned digital image analysis via binarization with Digimizer version 3.7.1 (Berkowitz and Sallee 2011). Other studies have required that 3 out of 5 IRIS tubes must display iron removal in order to be considered to have met criteria set by the HSTS (NTCHS 2007; Berkowitz and Sallee 2011). We also tested soils with αα-dipyridyl dye to provide additional data regarding anaerobic conditions (NTCHS 2009). To measure saturated conditions, we used groundwater-monitoring wells installed 50 cm (20 inches) below the soil surface (Noble 2006, Sprecher 2008, USACE 2005). We installed In-Situ Troll 500 (In-Situ, Inc., Fort Collins, CO) automated data-logging equipment to monitor and record groundwater levels twice daily. All equipment installation occurred in October 2012, and monitoring continued until April 2013, thereby capturing the typical annual wet period within the study area. We followed the recommendations of the NTCHS (2007) to analyze HSTS results. Analysis of growing season and rainfall normality was based on the findings of Sprecher and Warne (2000). We obtained precipitation data for the 3-month period preceding and during the study period (USDA-NRCS 1997) and used the direct antecedent rainfall evaluation method (DAREM) analysis to determine rainfall normality (Sumner et al. 2009). Several local plant experts documented vegetation data onsite to verify that a prevalence of hydrophytic plants occurred within each study area (Schotz 2010; see Acknowledgments). Additionally, we recorded indicators of wetland hydrology as outlined in the regional supplement to the USACE wetland delineation manual (Wakley et al. 2010). Results Hydrophytic vegetation Hydrophytic vegetation was dominant at all three study areas where frequent prescribed burns are a recurring management tool. In relation to the number of plant species present, the Sandhill Crane Refuge displayed the least diversity and lacked an overstory canopy (Fig. 1b). Grasses—mostly Andropogon spp. (bluestem), Aristida stricta Michx. (Pineland Threeawn Wiregrass)—and forbs were dominant. A few low-growing shrubs including Ilex glabra (L.) A. Gray (Inkberry) and Gaylussacia mosieri Small (Woolly Huckleberry) were also present. Obligate vegetation included Sarracenia alata Alph. Wood (Yellow Trumpets), Lycopodiella appressa (Chapm.) Cranfill (Southern Bog Clubmoss), Pogonia ophioglossoides (L.) Ker Gawl. (Snakemouth Orchid), Helianthus heterophyllus Nutt. (Variable-leaf Sunflower), and Pinguicula lutea Walt. (Yellow Butterwort). The overstory canopy was sparse at the two study areas located in Alabama, though Splinter Hill Bog contained a greater diversity of species. Longleaf Pine, Slash Pine, and Magnolia virginiana L. (Sweetbay Magnolia) occurred on both sites, as did Morella cerifera (L.) Small (Wax Myrtle), Inkberry, and Ilex coriacea Southeastern Naturalist J.F. Berkowitz, S.Page, and C.V. Noble 2014 Vol. 13, No. 4 726 (Pursh) Chapm. (Large Gallberry). Obligate wetland species present at both sites included Sarracenia leucophylla Raf. (White-topped Pitcher Plant), Drosera capillaris Poir. (Pink Sundew), Rhynchospora gracilenta A. Gray (Slender Beaksedge), Utricularia subulata L. (Zigzag Bladderwort), Southern Bog Clubmoss, Variableleaf Sunflower, Lachnanthes caroliniana (Lam.) Dandy (Carolina Redroot), and Lophiola aurea Ker Gawl. (Goldencrest). In the Washington County study area, additional obligate species included Sarracenia rubra subsp. wherryi F.W. Case & R.B. Case) Schnell (Wherry’s Redflower Pitcher Plant), Eriocaulon compressum Lam. (Flattened Pipewort), Drosera intermedia Hayne (Spoonleaf Sundew), and Yellow Butterwort. Additional obligates in the Splinter Hill study area included Nyassa biflora Walter (Swamp Tupelo), Sarracenia rosea F.W. Case & R.B. Case (Purple Pitcher Plant), Ludwigia virgata Michx. (Savannah Primrose-willow), Rhynchospora ciliaris (Michx.) C. Mohr (Fringed Beaksedge), Xyris ambigua Bey ex. Kunth (Coastal Plain Yelloweyed-grass), Drosera tracyi Macfarlane (Tracy’s Sundew), Helenium brevifolium (Nutt.) Alph. Wood (Shortleaf Sneezeweed), Xyris difformis Chapm. (Bog Yelloweyed-grass), and Sarracenia leucophylla x S. purpurea (a pitcher plant hybrid). Saturated conditions and indicators of wetland hydrology The saturated-conditions criteria of the HSTS require that the water table remain within 25 cm (10 inches) for >14 consecutive days during the growing season. The two Sandhill Crane Refuge sites failed to meet these criteria, with high water-table events limited to between 5 and 6 days duration. Four study areas met the hydrology portion of the HSTS (Table 1; Fig. 3), with hydrologic durations ranging from 15 to 89 consecutive days. DAREM analysis results demonstrate that the saturated-condition criteria of the HSTS were satisfied during normal or drier than normal periods (Table 2; also see Supplemental Tables 1–18, available online at https://www.eaglehill.us/SENAonline/suppl-files/s13-4-S2091-Berkowitz-s1, and, for BioOne subscribers, at http://dx.doi.org/10.1656/S2016.s1). Although HSTS criteria for saturated conditions were not met at 2 study sites, all study areas displayed indicators of wetland hydrology (Wakeley et al. 2010). Each location exhibited at least one primary and/or two secondary indicators of wetland Table 1. Summary HSTS data indicating anaerobic conditions and saturated conditions. Days = consecutive days of saturation Parameter Summary IRIS tubes with >30% αα-dipyridyl Anaerobic Saturated Study area removal reaction? Days conditions? conditions? HSTS met? Sandhill Crane A 0/3 No 6 No No No Sandhill Crane B 0/3 No 5 No No No Washington County A 2/3 Yes 89 Yes Yes Yes Washington County B 1/3 Yes 15 No Yes No Splinter Hill A 3/3 Yes 37 Yes Yes Yes Splinter Hill B 0/3 No 28 No Yes No Southeastern Naturalist 727 J.F. Berkowitz, S.Page, and C.V. Noble 2014 Vol. 13, No. 4 Figure 3. Wetland hydrologic-monitoring results collected at a) Sandhill Crane Refuge A, b) Sandhill Crane Refuge B, c) Washington County A, d) Washington County B, e) Splinter Hill A, and f) Splinter Hill B. The horizontal lines represent periods when the HSTS saturated-conditions criteria were met. All saturated conditions occurred during normal or dryer than normal rainfall periods as indicated in Table 2 (also see Supplemental Tables 1–18, available online at https://www.eaglehill.us/SENAonline/suppl-files/s13-4-S2091- Berkowitz-s1, and, for BioOne subscribers, at http://dx.doi.or g/10.1656/S2016.s1). Southeastern Naturalist J.F. Berkowitz, S.Page, and C.V. Noble 2014 Vol. 13, No. 4 728 hydrology. Observed wetland hydrology indicators included: B4, iron deposits; B13, aquatic fauna, C3, oxidized rhizospheres along living roots; C4, presence of reduced iron; B10, drainage patterns; C8, crawfish burrows; D2, geomorphic position; and D5, FAC neutral test. Anaerobic conditions and indicators of hydric soil Four of the 6 areas examined exhibited some iron removal from IRIS tubes and/ or positive reactions with αα-dipyridyl dye (Table 1). Washington County B showed iron removal from only 1 of 3 IRIS tubes, and a positive reaction to αα-dipyridyl dye, indicating some level of anaerobic conditions. However, Washington County B failed to meet the HSTS anaerobic conditions criteria because the duration of reducing conditions was unknown and there was insufficient iron removal from the majority of IRIS tubes. Two study sites—Washington County A and Splinter Hill A—displayed >30% iron removal from 2 out of 3 IRIS tubes and met the HSTS anaerobic conditions criteria. These sites also displayed a positive reaction with αα-dipyridyl dye. In general, soils within the study area displayed high-chroma colors beginning either at the surface or below a dark layer (e.g., 10YR 3/1) ranging between 5 cm and 20 cm (2–8 in) thick (Fig. 4). We described loamy/clayey soil textures during the site visit following Vasilas et al. (2010). All of the soil profiles we examined exhibited 2–37% distinct or prominent redoximorphic concentrations as pore linings and/or masses in near-surface layers. Additionally, several of the profiles examined contained redoximorphic depletions. The presence of redoximorphic features suggest that high water-tables and reducing conditions occur in each study area. Despite the presence of redoximorphic features in all soils, only one of the soils (Splinter Hill Bog A) meets an approved hydric-soil indicator (F3–depleted matrix). The lack of hydric soil indicators in all remaining sites results from the presence of matrix chroma-colors ≥3 or inadequate depths to meet the requirements of other hydric-soil indicators (e.g., F6–redox dark surface). Additionally, none of the sample locations occurred in closed depressions subject to ponding, thus preventing the application of hydric soil indicator F8–redox depre ssions. Table 2. Rainfall normality-analysis results based on the DAREM approach. For each month during the study period, the previous three months rainfall was evaluated and utilized to determine normality as described in Sumner et al. (2009). Month Sandhill Crane Refuge Washington County Splinter Hill November Normal Wet Normal December Dry Dry† Dry† January Normal Normal† Normal† February Dry Normal† Dry† March Normal Wet Normal April Normal Dry Normal †indicates the months during which a minimum of 14 consecutive days of saturated conditions occurred (NTCHS 2007). Southeastern Naturalist 729 J.F. Berkowitz, S.Page, and C.V. Noble 2014 Vol. 13, No. 4 Discussion Hydric soils typically exhibit morphological characteristics used, in conjunction with the presence of hydrophytic vegetation and indicators of wetland hydrology, to identify wetland boundaries. Hydric-soil characteristics form the basis of the Figure 4. Near-surface soil descriptions collected within the study area. *Note that only one soil profile (Splinter Hill Bog A; F3–Depleted Matrix) meets the criteria of an approved hydric soil field indicator. All other profiles failed to meet the criteria for a hydric soil indicator due to the presence of high chroma (≥3) colors. All soil profiles contain evidence of redoximorphic processes including: concentrations (C) and depletions (D) occurring in pore linings (PL) and within the soil matrix (M). Southeastern Naturalist J.F. Berkowitz, S.Page, and C.V. Noble 2014 Vol. 13, No. 4 730 hydric soil field-indicators and include the: 1) accumulation of organic materials near the soil surface, 2) reduction, translocation, and re-precipitation of iron and manganese oxides, and 3) formation of low-chroma (i.e., grey) colors within the soil matrix (Mausbach and Richardson 1994). However, some hydric soils lack these characteristics and require additional investigation (Megonigal et al. 1993, Rabenhorst and Parikh 2000, Tiner 1999, Vepraskas and Sprecher 1997). The vegetation and hydrology results presented above suggest that wetland processes occurred within each of the study areas. Notably, all study sites displayed indicators of wetland hydrology (e.g., crawfish burrows) and hydrophytic vegetation (e.g., predominance of many obligate plant species): characteristics that support a wetland determination (Tiner 1999). However, many of the soils we examined lacked the characteristic morphologies associated with hydric soils. Several scenarios provide potential explanations for the apparent disconnect between observed site conditions (e.g., obligate hydrophytic plants, wetland hydrology indicators) and the absence of hydric soil indicators. Factors preventing the formation of hydric soil morphologies at these sites include: low organic matter content, high iron concentrations, extensive bioturbation, presence of high-chroma minerals (e.g., chert), and short saturation intervals (Vepraskas and Sprecher 1997). These factors potentially work independently or in concert to limit the formation of hydric soil field-indicators within the study area. Many of the study areas examined display low surficial and near-surface organic matter contents as indicated by the lack of dark soil horizons (i.e., values ≤2). Under normal wet-soil conditions, organic matter accumulates as moisture increases (Daniels et al. 1971). In wet soils, organic matter accumulates due to water logging, soil acidity, low oxidation-reduction potential, and other factors (Fanning and Fanning 1989), and the amount of organic matter can be inversely related to the number of wetting and drying cycles. Groundwater-monitoring results displayed a high frequency of wetting and drying events, and the study areas lacking hydric soil indicators were characterized by short-duration, rapidly rising and falling water tables (Fig. 3a, b). Additionally, the surface vegetative cover consists of sparse assemblages of shrubs, grasses, and forbs which provide little organic matter residue, especially under a periodic regime of natural and prescribed fires. Further, extensive bioturbation from crawfish continually churned the surface and promoted bacterial respiration of organic matter through increased exposure to warm temperatures, sunlight, and oxygen. The frequency of wetting and drying cycles, lack of organic matter inputs from above- and belowground biomass, and increased bioturbation by crawfish potentially limited organic matter accumulation and the formation of hydric soil morphology. In addition to low amounts of organic matter, study areas exhibited high amounts of iron as observed in plinthite masses, iron nodules and concretions, and iron films seeping from discharge zones. It is possible that that the electro-redoximorphic system governing soil reduction and morphology was overwhelmed with dissolved iron. The very slowly permeable clay layers beneath pitcher plant-bog soils also Southeastern Naturalist 731 J.F. Berkowitz, S.Page, and C.V. Noble 2014 Vol. 13, No. 4 occurred below the neighboring upland soils, albeit at greater depth (USDS-NRCS 2013). In an area with >150 cm (60 inches) of mean annual precipitation, reduction reactions can continue at depths well below the surface, providing a lateral source of dissolved iron to low-lying wetlands (Blume 1988). Although additional research is required, positive reactions to αα-dipyridyl dye coupled with the lack of iron removal from IRIS tubes located in areas exhibiting high water tables provides some supporting evidence for such an influx of dissolved iron at these sites. One potential approach to address problematic hydric soils in the study area includes the application of an existing hydric soil field-indicator in a neighboring region, A16–coast prairie redox (currently approved for use in MLRA 150A of LRR T; USDA-NRCS 2006, Vasilas et al. 2010). Application of A16 requires “a layer starting within 15 cm (6 inches) of the soil surface that is at least 10 cm (4 inches) thick and has a matrix chroma of 3 or less with 2 percent or more distinct or prominent redox concentrations occurring as soft masses and/or pore linings”. The associated user notes mention that these hydric soils occur on depressional landforms and associated intermound landforms of the Lissie Formation—a deltaic plain of sand, silt, and clay of Pleistocene age. The user notes further explain that “Chroma-3 matrices are allowed because they may be the color of stripped sand grains or because few or common sand-sized reddish chert particles occur and may prevent obtaining chroma of 2 or less.” It should be noted that we observed chert particles in several of the study areas examined, potentially diluting the observed color and leading to the designation of high chroma for the pitcher plant-bog soils examined. As mentioned above, extensive bioturbation by crawfish provides another potential mechanism for the introduction of high-chroma subsurface materials into surface layers. Further examination indicates that several of the study areas lacking a hydric soil indicator would meet the requirements of A16–coast prairie redox. These findings suggest that A16 may provide a useful resource within pitcher plant bogs. However, additional data including the quantification of chert abundance will be required to determine the extent and reliability of A16 throughout the region, and further investigations are required to understand the mechanisms governing hydric soil morphology in the pitcher plant bogs studied. Whether addressed through the application of hydric soil indicator A16 or another approach, the data presented above indicate that additional research is required to fully reconcile the observed inconsistency between soils, hydrophytic plants, and indicators of wetland hydrology in pitcher plant bogs. The current study provides data indicating that high water-tables and some degree of anaerobic activity (e.g., redoximorphic features in soil profiles) occurred within the study sites. Additionally, we suggest a number of potential mechanisms preventing the formation of hydric soil morphologies. Future studies should focus on long-term monitoring of hydrology, plant distribution, and oxidation-reduction potentials. These data, in addition to examinations of soil chemistry and mineralogy, will improve management of unique pitcher plant-bog ecosystems. Southeastern Naturalist J.F. Berkowitz, S.Page, and C.V. Noble 2014 Vol. 13, No. 4 732 Summary The ecological factors that support pitcher plant-bog habitats are unique and not fully understood. Many of the soils associated with these ecosystems lack field indicators of hydric soils despite the presence of hydrophytic vegetation and indicators of wetland hydrology. Collected data demonstrates that some study areas meet the HSTS, yet retain high-chroma matrixes characteristic of non-wetland soils. We suggested several potential mechanisms preventing the formation of hydric soil morphologies including low organic-matter inputs, high rates of bioturbation, and the delivery of high iron-concentrations in soil waters. The application of an existing hydric soil indicator, A16–coast prairie redox, appears to have some applicability to the soils we studied. However, further testing and investigation are required to ensure appropriate management of these endemic natural areas. Acknowledgments Thanks to Jerome Langlinais, Charles Love, and Lawrence McGhee (NRCS-Alabama); Delaney Johnson, Mike Lilly, and Ralph Thornton (NRCS-Mississippi); the National Technical Committee for Hydric Soils; Al Schotz, Jim Teaford, Gina Todia, and Jim and Louise Duffy for plant community data; and Mississippi Sandhill Crane Refuge, the Natural Conservancy, and private landowners for study site access. All photos are credited to Loxley Soil Survey office staff and Ron Wooten of USACE-Galveston District. Literature Cited Berkowitz, J.F. 2009. Using IRIS tubes to monitor reduced conditions in soils: Project design. ERDC TN-WRAP-09-1. US Army Engineer Research and Development Center, Vicksburg, MS. 10 pp. Berkowitz, J.F., and J.B. Sallee. 2011. Investigating problematic hydric soils using water table measurements, IRIS tubes, soil chemistry, and application of the hydric soils technical standard. Soil Science Society of America Journal 75(6):2379–2385. Blume H.P. 1988. 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