''Quercus cornelius-mulleri'' is a North American species of

oak An oak is a tree or shrub in the genus ''Quercus'' (; Latin "oak tree") of the beech family, Fagaceae. There are approximately 500 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably ''L ...

known by the common name Muller oak, or Muller's oak. It was described to science in 1981 when it was segregated from the ''

Quercus dumosa ''Quercus dumosa'' is a species of plant in the family Fagaceae, belonging to the white oak section of the oak genus (''Quercus''). This tree goes by the common names coastal sage scrub oak and Nuttall's scrub oak. Description ''Quercus dumosa ...

'' complex and found to warrant species status of its own. It was named after ecologist

Cornelius Herman Muller Cornelius Herman ("Neil") Muller, born Müller, (July 22, 1909 – January 26, 1997) was an American botanist and ecologist who pioneered the study of allelopathy and oak classification. Personal life Müller was born in Collinsville, Illinois ...

. It is native to southern

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

and

Baja California Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...

, where it grows in

chaparral Chaparral ( ) is a shrubland plant community and geographical feature found primarily in the U.S. state of California, in southern Oregon, and in the northern portion of the Baja California Peninsula in Mexico. It is shaped by a Mediterranean c ...

, oak woodlands, and other habitat in foothills and mountains. It can most easily be observed in

Joshua Tree National Park Joshua Tree National Park is an American national park in southeastern California, east of San Bernardino and Los Angeles and north of Palm Springs, California, Palm Springs. It is named after the Joshua trees (''Yucca brevifolia'') native to t ...

and in the woodlands along the western margins of the

Colorado Desert California's Colorado Desert is a part of the larger Sonoran Desert. It encompasses approximately , including the heavily irrigated Coachella and Imperial valleys. It is home to many unique flora and fauna. Geography and geology The Colorado De ...

San Diego County, California San Diego County (), officially the County of San Diego, is a county in the southwestern corner of the U.S. state of California. As of the 2020 census, the population was 3,298,634, making it California's second-most populous county and the fi ...

.Nixon, K. C. (2002)
The Oak Biodiversity of California and Adjacent Regions.
US Forest Service Gen. Tech. Report

Description

''Quercus cornelius-mulleri'' is a bushy

shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...

not exceeding 3 meters (10 feet) in height. It is densely branched, its tangled twigs gray, brown, or yellowish, fuzzy when new and becoming scaly with age. The

evergreen In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, which ...

leaves are leathery and thick. They are bicolored: dull gray or yellow-green and faintly hairy on the upper surfaces, and white and quite woolly on the undersides. The wool on the undersides of the leaves is made up of star-shaped leaf hairs that are fused into microscopic plates. The leaf blades are oval with smooth or toothed edges, and measure in length. The fruit is an

acorn The acorn, or oaknut, is the nut of the oaks and their close relatives (genera ''Quercus'' and '' Lithocarpus'', in the family Fagaceae). It usually contains one seed (occasionally two seeds), enclosed in a tough, leathery shell, and borne ...

with a cap up to wide covered in light-colored scales and a cylindrical, round-ended nut up to long.

References

External links

*
United States Department of Agriculture Plants Profile: Quercus cornelius-mulleri
*
photo of herbarium specimen at Missouri Botanical Garden, collected in California in San Diego County in 1980
cornelius-mulleri Flora of Baja California Flora of the California desert regions Natural history of the California chaparral and woodlands Natural history of the Mojave Desert Natural history of the Peninsular Ranges Natural history of the Transverse Ranges Flora of California Plants described in 1981 Oaks of Mexico {{Quercus-stub