About Quercus pungens Liebm.
Quercus pungens Liebm., commonly called sandpaper oak, can grow as a small tree reaching up to 12 metres (39 feet) tall, or as a large shrub that forms thickets. Its bark is light brown and papery. Young gray twigs are covered in short velvety hairs, and become smooth as they age. Its buds are dark red-brown, with a sparse covering of hairs. The leathery leaves of this species are semi-evergreen; they start out bright glossy green and darken as they age. Their rough texture, created by tiny persistent hair bases, is where the common name sandpaper oak comes from. Its reddish inflorescence emerges in spring. Female catkins hold one to three flowers each, while male catkins hold many flowers. Acorn cups are shallow and covered in dense gray hairs. Acorns grow singly or in pairs, are light brown, broadly ovoid, and have a rounded apex. Sandpaper oak, often grouped with Vasey shin oaks, is abundant in the Edwards Plateau and the Trans-Pecos region of Texas. It also grows in the Guadalupe Mountains, extending west to the mountains of southeastern Arizona and southwestern New Mexico, as well as in northern and eastern Mexico, specifically the states of Chihuahua, Coahuila, Durango, Nuevo León, and Veracruz. This oak prefers to grow on dry limestone or igneous slopes at elevations between 800–2,000 m (2,600–6,600 ft) above sea level, in chaparral and desert scrub savanna. It most often grows in mixed communities with other oaks, juniper, and pinyon pine. In the chaparral formations of the Guadalupe Mountains, sandpaper oak is one of the dominant species, growing alongside true mountain-mahogany (Cercocarpus montanus) and desert ceanothus (Ceanothus greggii). Other plant species commonly associated with Quercus pungens include Mohr shin oak (Quercus mohriana), oneseed juniper (Juniperus monosperma), cane cholla (Opuntia imbricata), purplefruited pricklypear (Opuntia phaeacantha), Mexican buckeye (Ungnadia speciosa), Texas persimmon (Diospyros texana), hairy tridens (Erioneuron pilosum), and plateau oak (Quercus fusiformis).
