Quercus hinckleyi
| Quercus hinckleyi | |
|---|---|
| Scientific classification | |
| Kingdom: | Plantae |
| (unranked): | Angiosperms |
| (unranked): | Eudicots |
| (unranked): | Rosids |
| Order: | Fagales |
| Family: | Fagaceae |
| Genus: | Quercus |
| Species: | Q. hinckleyi |
| Binomial name | |
| Quercus hinckleyi C.H.Mull. 1951 | |
Quercus hinckleyi is a rare species of oak known by the common name Hinckley oak. It is native to northern Mexico (Chihuahua and Coahuila) and also to Texas in the United States, where it occurs in only two counties. The oak has probably become rare not because of habitat loss, but because today's climate in its native area is too dry.[1] It is federally listed as a threatened species of the United States.
Quercus hinckleyi is a shrub growing into a bushy, tangled thicket not more than 1.5 meters (5 feet) tall. The highly branched stems are coated in scaly gray bark and the smaller twigs are brown and sometimes waxy. The leaves are up to 1.5 centimeters (0.6 inch) long by 1.5 cm (0.6 inch) wide and have large, widely spaced teeth, resembling holly leaves. The blades are leathery, waxy, and blue-green in color. The fruit is an acorn 1 to 1.5 centimeters (0.4-0.6 inch) wide at the cap, the nut measuring up to 2 centimeters (0.8 inch) long.[2]
Quercus hinckleyi is known from Brewster and Presidio Counties in West Texas. It has also been found just across the Rio Grande in Mexico.[2][3] The plant grows in Chihuahuan Desert scrub habitat on limestone substrates.[1] The tree grows in very rocky soils or sometimes cracks in solid limestone outcrops.[4]
Climate change has been implicated as the main reason for the rarity of this plant. It was more abundant 10,000 years ago when this region of Texas was wetter; there are plentiful fossilized acorns of this species in rodent middens from that era.[1][5] It may have even been a dominant species.[2] Low rates of reproduction may also contribute to its rarity.[5] There are about 10 populations in Texas.[1] Most populations are located in Big Bend Ranch State Park.[1][4]
References
- 1 2 3 4 5 Quercus hinckleyi. Center for Plant Conservation.
- 1 2 3 Quercus hinckleyi. Flora of North America.
- ↑ Quercus hinckleyi. The Nature Conservancy.
- 1 2 USFWS. Quercus hinckleyi Five-year Review. September 2009.
- 1 2 Quercus hinckleyi. Texas Parks & Wildlife.
External links
- United States Department of Agriculture Plants Profile
- photo of herbarium specimen collected in Texas in 1950