''Quercus dumosa'' is a species of

plant Plants are predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all current definitions of Plantae exclud ...

in the family

Fagaceae The Fagaceae are a family of flowering plants that includes beeches, chestnuts and oaks, and comprises eight genera with about 927 species. Fagaceae in temperate regions are mostly deciduous, whereas in the tropics, many species occur as evergre ...

, belonging to the

white oak The genus ''Quercus'' contains about 500 species, some of which are listed here. The genus, as is the case with many large genera, is divided into subgenera and sections. Traditionally, the genus ''Quercus'' was divided into the two subgenera '' ...

section of the

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 ...

genus (''Quercus''). This tree goes by the common names coastal sage scrub oak and Nuttall's scrub oak.

Description

''Quercus dumosa'' is an evergreen

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 ...

growing 1 to 3 metres (40–120 inches or 3–10 feet) tall from a large, deep root network. The leaves have spiny or toothed edges. 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 ...

up to wide. Some individuals produce large crops of acorns, and some produce very few fruits. The acorns are dispersed by gravity as they fall from the tree, and by animals that pick them up, such as

squirrel Squirrels are members of the family Sciuridae, a family that includes small or medium-size rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrels. Squ ...

s and

jay A jay is a member of a number of species of medium-sized, usually colorful and noisy, passerine birds in the Crow family (biology), family, Corvidae. The evolutionary relationships between the jays and the magpies are rather complex. For examp ...

s. Animals eat them immediately or

cache Cache, caching, or caché may refer to: Places United States * Cache, Idaho, an unincorporated community * Cache, Illinois, an unincorporated community * Cache, Oklahoma, a city in Comanche County * Cache, Utah, Cache County, Utah * Cache Count ...

them for later. The acorns tend to

germinate Germination is the process by which an organism grows from a seed or spore. The term is applied to the sprouting of a seedling from a seed of an angiosperm or gymnosperm, the growth of a sporeling from a spore, such as the spores of fungi, fer ...

easily. Reproduction via seed generally occurs only in very moist years.

Taxonomy

The name ''Quercus dumosa'' was formerly widely applied to nearly all the scrub oaks of the white oak group of

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 ...

. The

concept Concepts are defined as abstract ideas. They are understood to be the fundamental building blocks of the concept behind principles, thoughts and beliefs. They play an important role in all aspects of cognition. As such, concepts are studied by s ...

of this species has gradually narrowed as

phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

research and

taxonomic Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ...

treatments have segregated out several species. Oaks previously placed under ''Q. dumosa'' include: * ''Q. turbinella'' * ''Q. john-tuckeri'' * ''Q. cornelius-mulleri'' * '' Q. berberidifolia'' * '' Q. pacifica'' However, the majority of oaks referred to as ''Quercus dumosa'' in the past are now regarded as ''Quercus berberidifolia''. The current concept of ''Q. dumosa'' is limited to the populations of scraggly shrub oaks with short petioles, cordate leaf bases, erect curly trichomes on the abaxial leaf surface, and narrow, acute acorns which almost always occur at low elevations and very often within sight of the ocean.

Distribution and habitat

''Quercus dumosa'' is found in California and Baja California. In Baja California, it is found from the

Mexico–United States border The Mexico–United States border ( es, frontera Estados Unidos–México) is an international border separating Mexico and the United States, extending from the Pacific Ocean in the west to the Gulf of Mexico in the east. The border traver ...

south to the Colonet peninsula. It is threatened by

habitat loss Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...

. The species lends its name to the plant community called the "''Quercus dumosa''

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 ...

", in which Coastal sage scrub oak and

toyon ''Heteromeles arbutifolia'' (; more commonly by Californian botanists), commonly known as toyon, is a common perennial shrub native to extreme southwest Oregon, California, and the Baja California Peninsula. It is the sole species in the genus ...

often co-dominate in chaparral.C. Michael Hogan (2008
Toyon: ''Heteromeles arbutifolia''
, GlobalTwitcher.com, ed. N. Stromberg.

Ecology

''Quercus dumosa'' grows primarily in sandy soils such as

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) ...

near the coast. Its habitat is often chaparral. This oak sprouts vigorously from its stump and root crown after

wildfire A wildfire, forest fire, bushfire, wildland fire or rural fire is an unplanned, uncontrolled and unpredictable fire in an area of Combustibility and flammability, combustible vegetation. Depending on the type of vegetation present, a wildfire ...

and develops a large canopy within a few years after a fire event. It sometimes co-dominates with ''

Ceanothus ''Ceanothus'' is a genus of about 50–60 species of Actinorhizal plant, nitrogen-fixing shrubs and small trees in the buckthorn family (Rhamnaceae). Common names for members of this genus are buckbrush, California lilac, soap bush, or just ceano ...

'' species as early as four years after a fire. This oak also does well in the absence of fire.

Allergenicity

The species is a severe allergen, with pollination generally occurring in spring.

References

External links

* * {{Taxonbar, from=Q2710410 dumosa Flora of California Flora of Baja California Natural history of the California chaparral and woodlands Natural history of the Peninsular Ranges Plants described in 1842 Taxa named by Thomas Nuttall Endangered biota of Mexico Endangered flora of North America Species endangered by habitat loss Taxonomy articles created by Polbot Oaks of Mexico