Common (Translated Scientific) Name: Rio Grande Palmetto - Texas Ebony - Cedar Elm Tamaulipan Riparian Scrub Group
Colloquial Name: Tamaulipan Riparian Scrub Forest
Hierarchy Level: Group
Type Concept: As currently circumscribed, this scrub forest group occurs in mesic environments including riparian areas and floodplains in the Tamaulipan region of southern Texas and northeastern Mexico. Stands are a unique mix of species from southeastern North America and subtropical Central America and may be dominated by Celtis laevigata, Cordia boissieri, Diospyros texana, Ebenopsis ebano, Ehretia anacua, Fraxinus berlandieriana, Leucaena pulverulenta, Parkinsonia aculeata, Sabal mexicana, Sideroxylon celastrinum, Ulmus crassifolia, and many other riparian plants. Other species may include Salix nigra, Taxodium mucronatum, Prosopis glandulosa, and Celtis ehrenbergiana. In the shrublands, the dense shrub canopy is a mix of species often including Vachellia farnesiana, Celtis ehrenbergiana, Haematoxylum brasiletto, Prosopis glandulosa, or Tecoma stans. The highly variable understory is dependent on canopy density and may include dense shrub or herbaceous layers dominated by neotropical species. Dominance of the herbaceous layer by invasive exotic grasses (e.g., Pennisetum ciliare and Urochloa maxima) is becoming more common.
Diagnostic Characteristics: No Data Available
Rationale for Nominal Species or Physiognomic Features:
Classification Comments: This group is a placeholder for wet-mesic, primarily forested vegetation in the Tamaulipan region of Texas and adjacent Mexico. As described, it may be better classified in a forest and woodland division. It is floristically variable, and some components may be better classified with related subtropical vegetation and others with related temperate or desert vegetation. Its placement in Interior Warm & Cool Desert Riparian Forest Macrogroup (M036) should be reviewed when more information about related subtropical vegetation is available.
Similar NVC Types:
Physiognomy and Structure: As currently circumscribed, this vegetation includes low woodlands, forests and shrublands. This vegetation is reported to have been as tall as 21 m historically (Jahrsdoerfer and Leslie 1988).
Floristics: Stands are a unique mix of species from southeastern North America and subtropical Central America and may be dominated by Cordia boissieri, Diospyros texana, Ebenopsis ebano, Ehretia anacua, Fraxinus berlandieriana, Leucaena pulverulenta, Parkinsonia aculeata, Phaulothamnus spinescens, Sabal mexicana, Sideroxylon celastrinum, Ulmus crassifolia, and many other riparian plants. Other species may include Salix nigra, Taxodium mucronatum, Prosopis glandulosa, and Celtis ehrenbergiana (= Celtis pallida). In these scrublands, the dense tall-shrub/short-tree canopy is a mix of species often including Vachellia farnesiana (= Acacia farnesiana), Celtis ehrenbergiana, Condalia hookeri, Haematoxylum brasiletto, Prosopis glandulosa, or Tecoma stans. The highly variable understory is dependent on canopy density and may include dense shrub or herbaceous layers dominated by neotropical species. Dominance of the herbaceous layer by invasive exotic grasses (e.g., Pennisetum ciliare and Urochloa maxima) is becoming more common.
Dynamics: Palm groves were once common in the lower Rio Grande Valley 80 miles from the Gulf of Mexico, but have since largely been converted to agriculture (Clover 1937, Everitt et al. 1996, Tremblay et al. 2005). Hydrologic regimes associated with the natural processes of the Rio Grande delta were important ecological processes for this group. This vegetation has been highly impacted by clearing, overgrazing, disruption of natural processes, and invasive species.
Environmental Description: This vegetation occurs in wet-mesic environments including riverbanks, floodplains, arroyos (ramaderos), and deltaic deposits that are temporarily to intermittently flooded (or were historically) and are dry during parts of the year. Soils are typically loams, silt loams, or clay loams and are somewhat deeper than those of the surrounding landscape. This vegetation is thought to have been once widespread, and now reduced to less than 90% of its former range through clearing for agriculture and hydrological alterations.
Geographic Range: This group occurs in the central and southern part of the Tamaulipan region of Texas and Mexico.
Nations: MX, US
States/Provinces: MXCO, MXNU, MXTM, TX
|US Forest Service Ecoregions (2007)|
Southwest Plateau and Plains Dry Steppe and Shrub Province
Confident or certain
Pecos Valley Section
Confident or certain
Omernik Ecoregions: 31:C
Confidence Level: Moderate
Confidence Level Comments:
Synonomy: >< Chihuahuan Thorn Forest (Jahrsdoerfer and Leslie 1988)
> Deciduous floodplain hardwood forest (Diamond 1998)
> Evergreen low forest (Diamond 1998)
> Hackberry-huisache Association (McLendon 1991)
> Huisache-prickly pear Association (McLendon 1991)
? Mesquite-granjeno Association (McLendon 1991)
> Mid-Delta Thorn Forest (Jahrsdoerfer and Leslie 1988)
> Mid-Valley Riparian Woodland (Jahrsdoerfer and Leslie 1988)
> Ramadero (Jahrsdoerfer and Leslie 1988)
> Southwestern Subtropical Upland Forests (Diamond 1998)
= Timber of the Rio Grande Valley below Rio Grande City (Bray 1901)
> Upper Valley Flood Forest (Jahrsdoerfer and Leslie 1988)
Concept Author(s): W.L. Bray (1901)
Author of Description: J. Teague
Version Date: 10Jun2015
- Bray, W. L. 1901. The ecological relations of the vegetation of western Texas. Botanical Gazette 32:102.
- Clover, E. U. 1937. Vegetational survey of the Lower Rio Grande Valley, Texas. Madrono 4:41-55, 77-100.
- Diamond, D. D. 1998. An old-growth definition for southwestern subtropical upland forests. General Technical Report SRS-21. USDA Forest Service, Southern Research Station, Asheville, NC. 7 pp.
- Everitt, J. H., F. W. Judd, D. E. Escobar, M. A. Alaniz, M. R. Davis, and W. MacWhorter. 1996a. Using remote sensing and spatial information technologies to map sabal palm in the Lower Rio Grande Valley of Texas. The Southwestern Naturalist 41(3):218-226.
- Faber-Langendoen, D., J. Drake, S. Gawler, M. Hall, C. Josse, G. Kittel, S. Menard, C. Nordman, M. Pyne, M. Reid, L. Sneddon, K. Schulz, J. Teague, M. Russo, K. Snow, and P. Comer, editors. 2010-2019a. Divisions, Macrogroups and Groups for the Revised U.S. National Vegetation Classification. NatureServe, Arlington, VA. plus appendices. [in preparation]
- Jahrsdoerfer, S. E., and D. M. Leslie. 1988. Tamaulipan brushland of the lower Rio Grande Valley of south Texas: Description, human impacts, and management options. USDI Fish & Wildlife Service. Biological Report 88(36). 63 pp.
- McLendon, T. 1991. Preliminary description of the vegetation of south Texas exclusive of coastal saline zones. Texas Journal of Science 43:13-32.
- Tremblay, T. A., W. A. White, and J. A. Raney. 2005. Native woodland loss during the mid-1900s in Cameron County, Texas. The Southwestern Naturalist 50(4):479-482.