Quercus grisea, commonly known as the gray oak, shin oak or scrub oak, is a deciduous

Deciduous

Deciduous means "falling off at maturity" or "tending to fall off", and is typically used in reference to trees or shrubs that lose their leaves seasonally, and to the shedding of other plant structures such as petals after flowering or fruit when ripe...

 or evergreen

Evergreen

In botany, an evergreen plant is a plant that has leaves in all seasons. This contrasts with deciduous plants, which completely lose their foliage during the winter or dry season.There are many different kinds of evergreen plants, both trees and shrubs...

 shrub or medium sized tree in the white oak group and is endemic to the south central montane regions of North America. It hybridizes with four other oak species where the ranges of each overlap, the Arizona white oak

Quercus arizonica

Quercus arizonica, the Arizona White Oak, is found dominantly in Arizona, southwest New Mexico, northeast Sonora and Chihuahua, all Madrean Sky Islands associated regions. It is a long-lived oak in the family Fagaceae, native to eastern North America...

 (Q. arizonica), the Gambel oak (Q. gambelii), the Mohr shin oak

Quercus mohriana

thumb|left|Typical oak savannaQuercus mohriana, commonly known as the Mohr oak, shin oak or scrub oak, is an evergreen shrub or small tree in the white oak group and is endemic to the south central montane regions of North America...

 (Q. mohriana) and the sandpaper oak

Quercus pungens

thumb|left|Typical oak savannaQuercus pungens, commonly known as the sandpaper oak or scrub oak, is an evergreen or sub-evergreen shrub or small tree in the white oak group and is endemic to south central North America. There is one recognised variety, Quercus pungens var. vaseyana, the Vasey shin...

 (Q. pungens).

Distribution

The gray oak is found growing from Texas

Texas

Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...

 westward into the mountains of central and southern New Mexico

New Mexico

New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...

, central and southeastern Arizona

Arizona

Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...

 and northern Mexico

Mexico

The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

. Through generally scarce, it is common in the Trans-Pecos

Trans-Pecos

The term Trans-Pecos, as originally defined in 1887 by the Texas geologist Robert T. Hill, refers to the portion of Texas that lies west of the Pecos River. The term is considered synonymous with "Far West Texas", a subdivision of West Texas...

 region of Texas.

Description

This oak may grow as a multi-stemmed shrub in drier situations but where the rainfall is sufficient, it grows into a medium size tree of up to about twenty metres with an irregular crown of twisted branches. The trunk is up to sixty centimetres in diameter with light gray bark which is fissured and cracked into small plates. The twigs are stout and a light reddish-brown colour, covered with grayish down. The leaves are alternate, leathery, long ovate, entire or with a few coarse teeth. They are grayish-green above and felted beneath and may fall in times of winter drought. The male catkins are yellowish-green and the female flowers are in small spikes growing in the leaf axils and appear in spring at the same time as the new leaves. The acorn cups are scaly, covered with fine hairs, and half as long as the acorns which grow singly or in pairs and are light brown.

Habitat

The gray oak occurs from 4,000 to 9,000 feet above sea level, growing in valleys and on ridges, on rocky slopes and on the banks of streams. It flourishes in semi-arid conditions characterized by mild winters, dry springs and hot summers. It can spread asexually

Asexual reproduction

Asexual reproduction is a mode of reproduction by which offspring arise from a single parent, and inherit the genes of that parent only, it is reproduction which does not involve meiosis, ploidy reduction, or fertilization. A more stringent definition is agamogenesis which is reproduction without...

 through the sprouting of root suckers and may form thickets. It grows in association with other oaks, species of juniper

Juniper

Junipers are coniferous plants in the genus Juniperus of the cypress family Cupressaceae. Depending on taxonomic viewpoint, there are between 50-67 species of juniper, widely distributed throughout the northern hemisphere, from the Arctic, south to tropical Africa in the Old World, and to the...

, Mexican pinyon (Pinus cembroides), pinyon pine (Pinus edulis), fendlerbush

Fendlera rupicola

Fendlera rupicola, commonly known as the cliff fendlerbush or the false mockorange, is a shrub that grows in dry locations in the south central montane regions of North America.-Description:...

 (Fendlera rupicola), bushy sage (Salvia ramosissima), Texas madrone

Arbutus xalapensis

Arbutus xalapensis, commonly known as the Texas Madrone or Texas Madroño, is a species of flowering plant in the heather family that is native to the southwestern United States , south through most of Mexico and Central America to Nicaragua...

 (Arbutus xalapensis ), Fremont barberry

Mahonia fremontii

Mahonia fremontii is a species of barberry known by the common name Frémont's mahonia .-Distribution:...

 (Mahonia fremontii), Louisiana sagewort

Artemisia ludoviciana

Artemisia ludoviciana is a species of sagebrush known by several common names, including silver wormwood, Louisiana wormwood, white sagebrush, and gray sagewort....

 (Artemisia ludoviciana) and soaptree yucca (Yucca elata).