''Quercus tardifolia'', the Chisos Mountains oak or lateleaf oak, is a rare North American species of oak. It has been found in the Chisos Mountains inside

Big Bend National Park Big Bend National Park is an American national park located in West Texas, bordering Mexico. The park has national significance as the largest protected area of Chihuahuan Desert topography and ecology in the United States, and was named after ...

in Texas, and in the nearby Sierra del Carmen across the Río Grande in northern

Coahuila Coahuila (), formally Coahuila de Zaragoza (), officially the Free and Sovereign State of Coahuila de Zaragoza ( es, Estado Libre y Soberano de Coahuila de Zaragoza), is one of the 32 states of Mexico. Coahuila borders the Mexican states of N ...

. ''Quercus tardifolia'' is an evergreen tree with gray

bark Bark may refer to: * Bark (botany), an outer layer of a woody plant such as a tree or stick * Bark (sound), a vocalization of some animals (which is commonly the dog) Places * Bark, Germany * Bark, Warmian-Masurian Voivodeship, Poland Arts, ...

and reddish-brown twigs. The

leaves A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

are flat, up to long, green on the upper surface and with woolly hairs on the underside, with a few shallow lobes.

Conservation

This species was thought to be extinct, however in May 25, 2022 a remaining specimen was found.SciTechDaily
"Clinging to Life: Scientists Rediscover Oak Tree Thought To Be Extinct."
The Morton Arboretum July 7, 2022

Etymology

The common name Chisos Mountains oak refers to the Chisos Mountains range where the species was discovered.

References

External links

Wildscreen Arkive, Chisos Mountains oak ''(Quercus tardifolia)''
— ''photo of herbarium specimen''.
Conabio Naturalista, ''Quercus tardifolia''
— ''photo of live specimen''. tardifolia Endemic flora of Texas Flora of Coahuila Flora of the Rio Grande valleys Big Bend National Park Plants described in 1936 Critically endangered flora of North America Critically endangered biota of Mexico Critically endangered flora of the United States Taxonomy articles created by Polbot {{Quercus-stub