Print Report
A3794 Alnus serrulata - Hamamelis vernalis - Salix caroliniana Riverscour Alliance
Type Concept Sentence: This alliance includes riverwash shrublands of gravel or bedrock substrates in the Ozark-Ouachita region. Common shrubs include Cornus obliqua, Ilex vomitoria, Hamamelis virginiana, and Phyllanthopsis phyllanthoides.
Common (Translated Scientific) Name: Hazel Alder - Ozark Witch-hazel - Coastal Plain Willow Riverscour Alliance
Colloquial Name: Ozark-Ouachita Riverscour
Hierarchy Level: Alliance
Type Concept: This alliance includes riverwash communities on gravel or bedrock substrates, primarily dominated by shrubs, and typically found in the Ozark-Ouachita region. These are deciduous or mixed evergreen-deciduous shrublands whose common components (which vary by zone and hydroperiod) include Alnus serrulata, Cephalanthus occidentalis, Cornus obliqua, Hamamelis vernalis, Hamamelis virginiana, Ilex vomitoria, Juniperus virginiana var. virginiana, Phyllanthopsis phyllanthoides, Physocarpus opulifolius, Quercus nigra, Salix caroliniana, Styrax grandifolius, and Vaccinium virgatum. These shrublands occupy various zones in and along rivers and streams in the south-central United States, including gravelly streambanks, upper and lower scour zones, as well as exposed bedrock in the highest portions of these areas. This vegetation is maintained by flash flooding events, and stands are scoured by floods that reach 5 m or more above normal summer pools. This vegetation is primarily known from the Ouachita region of western Arkansas and eastern Oklahoma, and the Ozarks of Arkansas and Missouri, but it may range into adjacent regions to the east.
Diagnostic Characteristics: This vegetation is characteristic of riverwash habitats of bedrock and gravel river and stream channels in the Ozark and Ouachita regions of the south-central United States; dominance is by one or more of the nominal shrubs.
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: This alliance comprises associations of diverse composition but similar habitats in the same region. The vegetation is variable in physiognomy and composition over its range, and the common components vary by zone and hydroperiod within these general riverine scour habitats.
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: The vegetation is variable in physiognomy, but is primarily composed of tall shrubs, with patches of herbaceous and sparse vegetation present as inclusions. The presence of trees is severely limited by the catastrophic and stochastic destructive action of floodwaters that may reach 5 m or more above normal summer pools.
Floristics: In some examples, Hamamelis vernalis is common and characteristic, but several other species may be locally abundant in the diverse microhabitats of this alliance, including Salix caroliniana in more open streambeds; Phyllanthopsis phyllanthoides (= Andrachne phyllanthoides) in drier scour zones; Juniperus virginiana in upper scour zones; Ilex vomitoria and Quercus nigra on bedrock and boulders on larger streams; and Alnus serrulata and Cephalanthus occidentalis in low, wet areas. On more stable substrates Acer rubrum, Liquidambar styraciflua, and Platanus occidentalis may be locally abundant. Other shrubs may include Amorpha fruticosa, Amorpha ouachitensis, Cornus obliqua, Crataegus spp., Ilex decidua, Hamamelis virginiana, Physocarpus opulifolius, Styrax grandifolius, and Vaccinium virgatum. Herbaceous species include Amsonia illustris, Ambrosia spp., Boltonia diffusa, Chasmanthium latifolium, Commelina erecta, Diodia virginiana, Ludwigia decurrens, Perilla frutescens (exotic), and Polygonum pensylvanicum. In addition, some sparsely vegetated patches are included here, which are dominated by a variable mixture of annual grasses, annual or biennial forbs, and annual vines under 1 m tall, including Arctium minus, Cuscuta gronovii, Cynodon dactylon, Cyperus esculentus, Digitaria sp., Diodia virginiana, Ipomoea coccinea, Lepidium virginicum, Lespedeza cuneata, Setaria pumila (= Setaria glauca), and Rubus trivialis (NatureServe unpubl. data). Scattered taller plants may be present, including Ambrosia artemisiifolia and Sorghum halepense.
Dynamics: This vegetation is maintained by flash flooding events, and stands are scoured by floods that reach 5 m or more above normal summer pools.
Environmental Description: These shrublands occupy various zones in and along rivers and streams in the south-central United States, including gravelly streambanks, upper and lower scour zones, as well as exposed bedrock in the highest portions of these areas. The vegetation may occur in narrow strips (1-10 m wide). The substrate includes loose cobbles but, on larger streams and rivers, also includes bedrock shelves or alluvial silt, where the various component vegetation types may intergrade.
Geographic Range: This vegetation is primarily known from the Ouachita region of western Arkansas and eastern Oklahoma, and the Ozarks of Arkansas and Missouri, but it may range into adjacent regions to the east.
Nations: US
States/Provinces: AR, KY?, MO, OK, TN
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.899846
Confidence Level: Low
Confidence Level Comments: No Data Available
Grank: GNR
Greasons: No Data Available
Concept Lineage: A.944 and A.1053, both singleton alliances (1/1); A.943 (1/7); A.946 (1/3); A.1850 (1/11)
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: ? Hamamelis vernalis shrubland alliance (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.
- Faber-Langendoen, D., and Midwest State Natural Heritage Program Ecologists. 1996. Terrestrial vegetation of the midwest United States. International classification of ecological communities: Terrestrial vegetation of the United States. The Nature Conservancy, Arlington, VA.
- Hoagland, B. W. 1998a. Classification of Oklahoma vegetation types. Working draft. University of Oklahoma, Oklahoma Natural Heritage Inventory, Norman. 43 pp.
- Nelson, P. 2010. The terrestrial natural communities of Missouri. Revised edition. Missouri Natural Areas Committee, Department of Natural Resources and the Department of Conservation, Jefferson City.
- Nelson, P. W. 1985. The terrestrial natural communities of Missouri. Missouri Natural Areas Committee, Jefferson City. 197 pp. Revised edition, 1987.