Print Report
A3308 Sedum spp. - Schizachyrium scoparium Comanchian Open Grassland Alliance
Type Concept Sentence: This alliance accommodates specialized glade vegetation, frequently dominated by low forbs (Lesquerella gordonii, Lesquerella ovalifolia), grasses (Schizachyrium scoparium, Sporobolus vaginiflorus), succulents (Sedum nuttallianum, Sedum pulchellum), and ferns (Pellaea ternifolia, Selaginella arenicola ssp. riddellii, Selaginella peruviana, Woodsia obtusa ssp. occidentalis) occurring on a variety of rock outcrops in the inland (non-coastal plain) parts of Texas and adjacent Oklahoma, including the Edwards Plateau, Lampasas Cutplain, Crosstimbers, and Blackland Prairie.
Common (Translated Scientific) Name: Stonecrop species - Little Bluestem Comanchian Open Grassland Alliance
Colloquial Name: Comanchian Open Grassland
Hierarchy Level: Alliance
Type Concept: This alliance accommodates specialized glade vegetation, frequently dominated by low forbs (Allium drummondii, Centaurium texense, Croton monanthogynus, Houstonia micrantha, Lesquerella gordonii, Lesquerella ovalifolia, Minuartia patula, Valerianella amarella), grasses (Bouteloua curtipendula, Bouteloua hirsuta, Schizachyrium scoparium, Sporobolus vaginiflorus), succulents (Sedum nuttallianum, Sedum pulchellum, Portulaca sp.), and ferns (Pellaea ternifolia, Selaginella arenicola ssp. riddellii, Selaginella peruviana, Woodsia obtusa ssp. occidentalis). It occurs on granite, schist, gneiss, and limestone rock outcrops in the inland (non-coastal plain) parts of Texas and adjacent Oklahoma, including the Edwards Plateau, Lampasas Cutplain, Crosstimbers, and Blackland Prairie. This vegetation may occur as large to small patches embedded in a matrix of woodlands, open forests, or perennial grass-dominated prairies. Bare rock may comprise 90% of the larger area, but vegetative cover with the patches is often 100%.
Diagnostic Characteristics: This is specialized glade vegetation, frequently dominated by low forbs, annual grasses, and succulents, found in the inland (non-coastal plain) parts of Texas and adjacent Oklahoma.
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: This alliance is redundant to the group concept. There is simply not enough information about this vegetation to subdivide it into alliances. The suite of associations is probably not complete for this broad area. More information might support separating this vegetation into alliances based on substrate chemistry, i.e., acidic versus calcareous.
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: This vegetation is frequently dominated by low forbs, annual grasses, and succulents, and occurs in patches on granitic and limestone rock outcrops. Bare rock may comprise 90% of the larger area, but vegetative cover within the patches is often 100%. Adjacent vegetation may include tallgrass prairie or oak - juniper woodlands.
Floristics: Vegetation varies across substrates and seasonally. Some species occurring in limestone glades include Allium drummondii, Bouteloua curtipendula, Bouteloua hirsuta, Centaurium texense, Chamaesyce nutans, Crassula drummondii, Croton monanthogynus, Galium virgatum, Houstonia micrantha, Lesquerella gordonii, Lesquerella ovalifolia, Mentzelia oligosperma, Minuartia patula, Oenothera macrocarpa (= Oenothera missouriensis), Opuntia humifusa, Portulaca sp., Rotala ramosior, Sedum nuttallianum, Sedum pulchellum, Sporobolus vaginiflorus (var. ozarkanus and var. vaginiflorus), Phemeranthus parviflorus, and Valerianella amarella. Nostoc commune is common and forms algal mats. Other taxa that are commonly found in crevices of limestone sheets and drier edges include Anemone berlandieri, Asclepias asperula, Bouteloua curtipendula, Bouteloua rigidiseta, Draba cuneifolia, Evax verna, Hedeoma reverchonii, Stenaria nigricans, Heliotropium tenellum, Lesquerella gracilis, Lithospermum incisum, Opuntia sp., Orobanche sp., Paronychia virginica, Penstemon cobaea, Spiranthes magnicamporum, Tetraneuris linearifolia, Thelesperma filifolium, and Zigadenus nuttallii.
Species occurring on acidic outcrops (granite, schist, gneiss) include scattered patches of crustose and foliose lichens, mosses, and several ferns and fern allies, including Cheilanthes lindheimeri, Cheilanthes tomentosa, Pellaea ternifolia, Selaginella arenicola ssp. riddellii, Selaginella peruviana, and Woodsia obtusa ssp. occidentalis. Typical species that occur in areas where shallow sand or gravel accumulate include Aphanostephus skirrhobasis, Campanula reverchonii, Helenium amarum, Hypericum gentianoides, Plantago wrightiana, Sedum nuttallianum, and Phemeranthus parviflorus (= Talinum parviflorum). Areas with deeper soils are dominated by Schizachyrium scoparium occurring with other grasses such as Bouteloua hirsuta, Bouteloua curtipendula, and Aristida purpurea. Large crevices that contain sufficient soil accumulation support woody species characteristic of the surrounding woodland, including Quercus stellata, Quercus marilandica, and Carya texana. Narrow, shallow crevices harbor species tolerant of the most xeric conditions, including Echinocereus reichenbachii, Eriogonum tenellum, and Cylindropuntia leptocaulis (= Opuntia leptocaulis).
Species occurring on acidic outcrops (granite, schist, gneiss) include scattered patches of crustose and foliose lichens, mosses, and several ferns and fern allies, including Cheilanthes lindheimeri, Cheilanthes tomentosa, Pellaea ternifolia, Selaginella arenicola ssp. riddellii, Selaginella peruviana, and Woodsia obtusa ssp. occidentalis. Typical species that occur in areas where shallow sand or gravel accumulate include Aphanostephus skirrhobasis, Campanula reverchonii, Helenium amarum, Hypericum gentianoides, Plantago wrightiana, Sedum nuttallianum, and Phemeranthus parviflorus (= Talinum parviflorum). Areas with deeper soils are dominated by Schizachyrium scoparium occurring with other grasses such as Bouteloua hirsuta, Bouteloua curtipendula, and Aristida purpurea. Large crevices that contain sufficient soil accumulation support woody species characteristic of the surrounding woodland, including Quercus stellata, Quercus marilandica, and Carya texana. Narrow, shallow crevices harbor species tolerant of the most xeric conditions, including Echinocereus reichenbachii, Eriogonum tenellum, and Cylindropuntia leptocaulis (= Opuntia leptocaulis).
Dynamics: No Data Available
Environmental Description: This alliance occurs on thin soil of granite, schist, gneiss, and limestone rock outcrops in central Texas and central and western Oklahoma. Bare rock may make up 90% of the area dotted with patches of vegetation. Shallow depressions may pool moisture during rainy periods, but become desiccated and baked in the heat of summer.
Geographic Range: This vegetation is found in the inland (non-coastal plain) parts of Texas and central and western Oklahoma.
Nations: US
States/Provinces: OK, TX
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.899432
Confidence Level: Low
Confidence Level Comments: No Data Available
Grank: GNR
Greasons: No Data Available
Concept Lineage: No Data Available
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: > Lesquerella (gordonii, ovalifolia) herbaceous alliance (Hoagland 2000)
> Sedum pulchellum herbaceous association (Hoagland 1998a)
> Sedum pulchellum herbaceous association (Hoagland 1998a)
- 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.
- Hoagland, B. 2000. The vegetation of Oklahoma: A classification for landscape mapping and conservation planning. The Southwestern Naturalist 45(4):385-420.
- Hoagland, B. W. 1997. Preliminary plant community classification for Oklahoma. Unpublished draft document, version 35629. University of Oklahoma, Oklahoma Natural Heritage Inventory, Norman. 47 pp.
- Hoagland, B. W. 1998a. Classification of Oklahoma vegetation types. Working draft. University of Oklahoma, Oklahoma Natural Heritage Inventory, Norman. 43 pp.
- Hoagland, B. W. 1998b. The vegetation of Oklahoma: A classification for landscape mapping and conservation planning. Oklahoma Biological Survey. University of Oklahoma, Norman.