Quercus robusta 

Scope: Global
Language: English

Translate page into:

Taxonomy [top]

Kingdom Phylum Class Order Family
Plantae Tracheophyta Magnoliopsida Fagales Fagaceae

Scientific Name: Quercus robusta C.H.Mull.
Common Name(s):
English Robust Oak
Taxonomic Source(s): Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico. 16+ vols. New York and Oxford. Vol. 3, 1997.

Assessment Information [top]

Red List Category & Criteria: Data Deficient ver 3.1
Year Published: 2017
Date Assessed: 2016-11-15
Assessor(s): Beckman, E.
Reviewer(s): Oldfield, S.
Contributor(s): McNeil-Marshall, A.
Because there is not yet agreement regarding the taxonomic status of Q. robusta, more research will be necessary before a full assessment is possible. This leaves the species within the Data Deficient category. If species status is further supported, the species would very likely fall into the Critically Endangered category under criterion D, with less than 50 individuals remaining.
Previously published Red List assessments:

Geographic Range [top]

Range Description:Quercus robusta is believed to be endemic to the Chisos Mountains range of southwest Texas, and currently known from one small area in Big Bend National Park (Poole et al. 2007). There is continued taxonomic debate surrounding the status of this species, with C. H. Muller describing the species in 1934, deeming it a hybrid between Q. emoryi and Q. gravesii in the mid-20th century, and finally reviewing the case again more recently and concluding Robust Oak to be a true species (FNA 1993). There is some possibility Q. robusta exists within northern Mexico, but no evidence has yet been found (NatureServe 2015). The species is not present in Valencia's authoritative taxonomic publication from 2006, regarding Fagaceae of Mexico.
Countries occurrence:
United States (Texas)
Additional data:
Number of Locations:1
Range Map:Click here to open the map viewer and explore range.

Population [top]

Population:NatureServe lists Q. robusta with only one verified occurrence, located in Boot Spring of Big Bend National Park. Other canyons in the Chisos Mountains could contain the species and there are about four unverified occurrences within the area, as of 2002 (NatureServe 2015).

Q. robusta is also mentioned in a recent study designed to identify soil type and distribution within the Sierra de Guadelupe, a State Park covering the cresent-shaped, mountainous region located just north of Mexico city. Its area is approximately 53 km2. The park's boundaries are defined by the surrounding urban growth, which has significantly impacted the area. One of the sites for soil categoration is described as "high slope; andesites tuffs; Pinus radiata, P. hallepensis, Quercus robusta, Agave sp., Q. microfila, Opuntia sp." (Flores-Román et al. 2009). There has been no further verification of this Q. robusta specimen, either its correct identification or provenance.

Current Population Trend:Unknown
Additional data:

Habitat and Ecology [top]

Habitat and Ecology:Robust Oak is large compared to other trees within the Chisos Mountains, and is found occupying the lowlands of moist wooded canyons where a creek sometimes flows, at around 1,500 m (A. McNeil-Marshal pers. comm. 2016) (FNA 1993).

Use and Trade [top]

Use and Trade: Researching tree species richness, density, and composition patterns along the gradient of urbanization surrounding Mexico City, Ortega-Alvarez et al. (2011) list the presence of eight Robust Oaks ("exotic") within 120 circular sampling plots (25 m radius). Perhaps Q. robusta is utilized within Mexican landscaping, or has been misidentified here.

Threats [top]

Major Threat(s): Although the species lies within a National Park, possible threats still include drought, fire, human impact during recreation, and potentially, flood (A. McNeil-Marshall pers. comm. 2016).

Conservation Actions [top]

Conservation Actions: This species is located within a U.S. National Park, providing protection from excess human disturbance, but further study, propagation, and reintroduction would be necessary to secure the species' existance. According to Botanic Gardens Conservation International, there are currently no ex situ specimens worldwide.

Citation: Beckman, E. 2017. Quercus robusta. The IUCN Red List of Threatened Species 2017: e.T34021A88668862. . Downloaded on 23 May 2018.
Disclaimer: To make use of this information, please check the <Terms of Use>.
Feedback: If you see any errors or have any questions or suggestions on what is shown on this page, please provide us with feedback so that we can correct or extend the information provided