Quercus austrina

Quercus austrina, the bastard white oak^[3] or bluff oak, is an oak species that is endemic to the southeastern United States from Mississippi to the Carolinas, with a few isolated populations in Arkansas.^[4][5]

Quercus austrina
Conservation status
Vulnerable  (IUCN 3.1)[1]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Fagales
Family:	Fagaceae
Genus:	Quercus
Subgenus:	Quercus subg. Quercus
Section:	Quercus sect. Quercus
Species:	Q. austrina
Binomial name
Quercus austrina Small
Natural range for Quercus austrina
Synonyms[2]
Quercus durandii var. austrina (Small) E.J.Palmer

Quercus austrina can grow to a height of 45 to 60 feet (13.5–18 meters) with a spread of 35 to 50 feet (10.5–15 m). Leaves are narrow, with shallow rounded lobes. It tends to grow in wet habitats, such as on river bluffs, river bottoms, and flatwoods, and generally over basic substrates, such as mafic rocks, shells, or calcareous sediment.^[4][6]

Quercus austrina specimens have often been misidentified as either Q. sinuata or Q. nigra.^[4]

Quercus austrina is tolerant to clay, sand, loam, acidic, and well-drained soils. Also, it requires a lot of sun and its drought tolerance is high.^[7]

National champion

The largest known bluff oak in the United States appeared on the National Register of Champion Trees in 2015. Located in Wakulla, Florida, the national champion specimen of Quercus austrina was nominated in 2009 by George Apthorp and crowned on September 1, 2015. It was last measured in 2014. By that time, the champion tree had attained a trunk circumference of 10 ft 8 in (3.25 m), a height of 129 ft (39 m) and a crown spread of 70 feet.^[8] The American Forests formula for assigning point scores to nominated trees is trunk circumference (in inches) + height (in feet) + 1⁄4 average crown spread (in feet), resulted in an overall score of 275 points.

References

1. Beckman, E. (2017). "Quercus austrina". IUCN Red List of Threatened Species. 2017: e.T194067A2296028. doi:10.2305/IUCN.UK.2017-2.RLTS.T194067A2296028.en. Retrieved 12 November 2021.
2. "Quercus austrina Small". World Checklist of Selected Plant Families. Royal Botanic Gardens, Kew – via The Plant List. Note that this website has been superseded by World Flora Online
3. USDA, NRCS (n.d.). "​Quercus austrina​". The PLANTS Database (plants.usda.gov). Greensboro, North Carolina: National Plant Data Team. Retrieved 30 July 2015.
4. Nixon, Kevin C. (1997). "Quercus austrina". In Flora of North America Editorial Committee (ed.). Flora of North America North of Mexico (FNA). Vol. 3. New York and Oxford: Oxford University Press – via eFloras.org, Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
5. "Quercus austrina". County-level distribution map from the North American Plant Atlas (NAPA). Biota of North America Program (BONAP). 2014.
6. Flora of the Southern and Mid-Atlantic States by Alan S. Weakley
7. Edward F. Gilman, Dennis G. Watson (2019-04-11). "Quercus austrina: Bluff Oak". edis.ifas.ufl.edu. Retrieved 2019-10-17.
8. "Bluff Oak (Quercus austrina)". American Forests. 2016-09-15. Retrieved 2021-03-22.