Print Report

A4093 Iva angustifolia - Clinopodium arkansanum - Distichlis spicata West Gulf Coastal Plain Saline & Weches Bedrock Grassland Alliance

Type Concept Sentence: This distinctive vegetation represents moist to wet glades and barrens found in the West Gulf Coastal Plain of the United States in Arkansas, Louisiana and Texas, on saturated saline soils and on the Weches Formation (glauconitic clay).

Common (Translated Scientific) Name: Narrowleaf Marsh-elder - Limestone Calamint - Saltgrass West Gulf Coastal Plain Saline & Weches Bedrock Grassland Alliance

Colloquial Name: West Gulf Coastal Plain Saline & Weches Barrens & Glade

Hierarchy Level:  Alliance

Type Concept: This alliance accommodates moist to wet glades and barrens found in the West Gulf Coastal Plain of the United States in Arkansas, Louisiana and Texas, including glauconitic clay (Weches) glades and barrens and inland wet saline flats. The wetter inland saline prairies are dominated by Eleocharis sp. and Iva angustifolia. The shrub stratum consists of widely scattered individuals of Sabal minor and Baccharis halimifolia. The herbaceous stratum consists of scattered patches of Bacopa monnieri, Distichlis spicata, Eleocharis spp., Fimbristylis spp., Iva angustifolia (an annual), Juncus sp., Schoenoplectus spp., and others. Additional characteristic plant species that may be found in examples of this alliance include Aristida dichotoma, Aristida longespica, Aristida purpurascens, Camassia scilloides, Clinopodium arkansanum, Delphinium carolinianum, Diodia teres, Euthamia leptocephala, Houstonia rosea, Krameria lanceolata, Piptochaetium avenaceum, Sabatia campestris, Schizachyrium scoparium, Sedum pulchellum, Sporobolus clandestinus, Sporobolus silveanus, Sporobolus vaginiflorus, Phemeranthus calycinus, and Tridens strictus, as well as the shrubs Baccharis halimifolia and Crataegus berberifolia. The alliance is dominated by prairie-like vegetation, and examples are primarily herbaceous-dominated, but can contain scattered shrubs and trees, or have these present at the edges of occurrences. The herbaceous flora is diverse and varies considerably seasonally. These scattered vegetation patches are known from outcrops of saline material apparently associated with saline seepage from inland salt domes. The clayey soils (Bonn series, a Glossic Natraqualf) are saturated to rarely flooded with saline seepage. Saline springs form artesian mudpots or "ooze mounds" at scattered locations. The vegetation is patchy, with much bare soil.

Diagnostic Characteristics: Moist to wet glades and barrens found in the West Gulf Coastal Plain of the United States in Arkansas, Louisiana and Texas. These are on saturated saline soils or Weches glauconitic clays and have distinctive herbaceous floras and very low cover of trees.

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: The old Bigelowia nuttallii Herbaceous Alliance (A.1617), whose associations have in common the presence of Bigelowia nuttallii as a seasonal aspect dominant, has been split into its West Gulf Coastal Plain (this alliance) and Southern Coastal Plain (A4091) components. This is based on the assumption that differences in the total floristics of these associations, despite the aforementioned seasonal aspect dominance of Bigelowia nuttallii, would support this separation. This assumption should be examined more carefully. The current plan is to separate the Nepheline-Syenite components (CEGL008421, CEGL008422) into another alliance, ~Sporobolus clandestinus - Clinopodium arkansanum - Delphinium carolinianum Nepheline Syenite Bedrock Grassland Alliance (A4094)$$, and then to separate the drier phases of glades and barrens (dry Saline plus Catahoula) from the moister phases (wet Saline plus Weches), creating three alliances (Nepheline-Syenite, drier Saline-Catahoula, and moister Saline-Weches). Another alternative was to place the saline barrens/glades associations (CEGL003904, CEGL004171, CEGL004274, CEGL007803, CEGL008418, CEGL008419) into their own alliance, distinct from the others (Nepheline-Syenite, Catahoula, and Weches glades and barrens). That has been rejected.

Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: These glades and barrens, found on saturated saline soils or Weches glauconitic clays, have distinctive herbaceous floras and very low cover of trees.

Floristics: Stands are typically dominated by a diverse assemblage of forbs and graminoids, with the dominant species being variable among the several associations. The wetter inland saline prairies are dominated by Eleocharis sp. and Iva angustifolia. The shrub stratum consists of widely scattered individuals of Sabal minor and Baccharis halimifolia. The herbaceous stratum consists of scattered patches of Bacopa monnieri, Distichlis spicata, Eleocharis spp., Fimbristylis spp., Iva angustifolia (an annual), Juncus sp., Schoenoplectus spp., and others. Characteristic plant species that may be found in examples of this alliance include Aristida dichotoma, Aristida longespica, Aristida purpurascens, Camassia scilloides, Clinopodium arkansanum, Delphinium carolinianum, Distichlis spicata, Diodia teres, Eleocharis spp., Euthamia leptocephala, Fimbristylis spp., Houstonia rosea, Iva angustifolia, Krameria lanceolata, Piptochaetium avenaceum, Sabatia campestris, Schizachyrium scoparium, Schoenoplectus spp., Sedum pulchellum, Sporobolus clandestinus, Sporobolus silveanus, Sporobolus vaginiflorus, Phemeranthus calycinus (= Talinum calycinum), and Tridens strictus, as well as the shrubs Baccharis halimifolia and Crataegus berberifolia. The herbaceous stratum consists of scattered patches of Bacopa monnieri, Distichlis spicata, Iva angustifolia (an annual), and others. Other characteristic species in some Weches examples include Allium drummondii, Anemone caroliniana, Arnoglossum plantagineum (= Cacalia plantaginea), Chamaesyce nutans (= Euphorbia nutans), Croton monanthogynus, Galium virgatum, Ipomopsis rubra, Minuartia patula (= Arenaria patula), Opuntia spp., and Valerianella radiata. Endemic annuals include Leavenworthia aurea var. texana (= Leavenworthia texana) and Lesquerella pallida. A scattered shrub layer, including Cercis canadensis, Cornus drummondii, Juniperus virginiana, and Sideroxylon lanuginosum, may be present on some sites. Some areas are dominated by various clonal wetland graminoids, including Eleocharis spp., Fimbristylis spp., Juncus spp., Schoenoplectus spp. (= Scirpus spp.), and Spartina pectinata. The vegetation is patchy, with much bare soil. The shrub stratum consists of widely scattered individuals of Baccharis halimifolia and Sabal minor. Forbs are scattered and include Hibiscus lasiocarpos (= Hibiscus moscheutos ssp. lasiocarpos), Phyla sp., and Pluchea sp. The exotic Alternanthera paronichyoides var. amazonica may also be present. One association, ~Baccharis halimifolia - Crataegus berberifolia / Eleocharis sp. - Tridens strictus - Euthamia leptocephala Shrubland (CEGL003904)$$, is characteristically more shrub-dominated rather than herb-dominated, but is placed here rather than in a separate alliance. More information is needed.

Dynamics:  No Data Available
Environmental Description:  The saturated saline components of this alliance are known from outcrops of saline material apparently associated with inland salt domes. The clayey soils (Bonn series, a Glossic Natraqualf) are saturated to rarely flooded with saline seepage. Saline springs form artesian mudpots or "ooze mounds" at scattered locations. The vegetation is patchy, with much bare soil. In some Weches examples, the outcrops are exposed by natural erosion of hillside slopes. Soils are mapped as Trawick series (Mollic Hapludalfs) and are shallow, rocky, and basic, which inhibits growth of woody vegetation. Outcrops are seepy and saturated during winter and early spring but become hard and dry in the summer. Enormous seasonal variations in species dominance can occur.
Geographic Range: Examples of this alliance are found in the West Gulf Coastal Plain of the United States in Arkansas, Louisiana and Texas.

Nations: US

States/Provinces:  AR, LA, TX


Confidence Level: Low

Confidence Level Comments: No Data Available
Grank: GNR

Greasons: No Data Available
Type Name Database Code Classification Code
Class 2 Shrub & Herb Vegetation Class C02 2
Subclass 2.B Temperate & Boreal Grassland & Shrubland Subclass S18 2.B
Formation 2.B.2 Temperate Grassland & Shrubland Formation F012 2.B.2
Division 2.B.2.Nh Southeastern North American Grassland & Shrubland Division D102 2.B.2.Nh
Macrogroup 2.B.2.Nh.3 Poverty Dropseed - Little Bluestem - Calamint species Southern Barrens & Glade Macrogroup M308 2.B.2.Nh.3
Group 2.B.2.Nh.3.a Little Bluestem - Limestone Calamint - Nuttall''s Rayless-goldenrod Southeastern Coastal Plain Barrens & Glade Group G584 2.B.2.Nh.3.a
Alliance A4093 Narrowleaf Marsh-elder - Limestone Calamint - Saltgrass West Gulf Coastal Plain Saline & Weches Bedrock Grassland Alliance A4093 2.B.2.Nh.3.a
Association CEGL003904 Groundsel-tree - Barberry Hawthorn / Spikerush species - Longspike Tridens - Bushy Goldentop Shrubland CEGL003904 2.B.2.Nh.3.a
Association CEGL004171 Spikerush species - Narrowleaf Marsh-elder - Saltgrass Grassland CEGL004171 2.B.2.Nh.3.a
Association CEGL007797 Widow''s-cross - Limestone Calamint - Poverty Dropseed Grassland CEGL007797 2.B.2.Nh.3.a
Association CEGL007803 Spikerush species - Bulrush species - Fimbry species - Rush species Southeastern Coastal Plain Inland Salt Flat Sparse Vegetation CEGL007803 2.B.2.Nh.3.a
Concept Lineage: The associations placed here are from A.1015 (1/2), A.1459(1/1), A.1820 (1/4), and A.1924 (1/1).

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available
Synonomy: < Wet Saline Prairie (Smith 1996b)
Concept Author(s): M. Pyne, in Faber-Langendoen et al. (2014)

Author of Description: M. Pyne

Acknowledgements: We have incorporated significant descriptive information previously compiled by R. Evans, L.M. Smith, R.L. Turner, and A.S. Weakley, as well as C.S. Reid, P.L. Faulkner, M H. MacRoberts, B.R. MacRoberts, and M. Bordelon.

Version Date: 03-14-14
  • Faber-Langendoen, D., J. Drake, M. Hall, G. Kittel, S. Menard, C. Nordman, M. Pyne, M. Reid, M. Russo, K. Schulz, L. Sneddon, K. Snow, and J. Teague. 2013-2019b. Screening alliances for induction into the U.S. National Vegetation Classification: Part 1 - Alliance concept review. NatureServe, Arlington, VA.
  • Mahler, W. E. 1987. Leavenworthia texana (Brassicaceae), a new species from Texas. Sida 12(1):239-242.
  • Nixon, E. S., J. R. Ward, and B. L. Lipscomb. 1983b. Rediscovery of Lesquerella pallida (Cruciferae). Sida 10:167-175.
  • Nixon, E. S., and R. J. George. 1990. The herbaceous flora of three Weches formation outcrops in eastern Texas. Sida 14:117-127.
  • Reid, C. S., P. L. Faulkner, M. H. MacRoberts, B. R. MacRoberts, and M. Bordelon. 2010. Vascular flora and edaphic characteristics of saline prairies in Louisiana. Journal of the Botanical Research Institute of Texas 4(1):357-379.
  • Smith, L. M. 1996b. The rare and sensitive natural wetland plant communities of interior Louisiana. Unpublished document. Louisiana Department of Wildlife and Fisheries, Louisiana Natural Heritage Program, Baton Rouge. 38 pp.