''Quercus dumosa'' is a species of

plant Plants are the eukaryotes that form the Kingdom (biology), kingdom Plantae; they are predominantly Photosynthesis, photosynthetic. This means that they obtain their energy from sunlight, using chloroplasts derived from endosymbiosis with c ...

in the family

Fagaceae The Fagaceae (; ) are a family of flowering plants that includes beeches, chestnuts and oaks, and comprises eight genera with around 1,000 or more species. Fagaceae in temperate regions are mostly deciduous, whereas in the tropics, many species ...

, belonging to the

white oak ''Quercus'' subgenus ''Quercus'' is one of the two subgenera into which the genus ''Quercus'' was divided in a 2017 classification (the other being subgenus ''Cerris''). It contains about 190 species divided among five sections. It may be calle ...

section of the

oak An oak is a hardwood tree or shrub in the genus ''Quercus'' of the beech family. They have spirally arranged leaves, often with lobed edges, and a nut called an acorn, borne within a cup. The genus is widely distributed in the Northern Hemisp ...

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 or 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 by their multiple ...

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 is the nut (fruit), nut of the oaks and their close relatives (genera ''Quercus'', ''Notholithocarpus'' and ''Lithocarpus'', in the family Fagaceae). It usually contains a seedling surrounded by two cotyledons (seedling leaves), en ...

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-sized rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrel ...

s and jays. Animals eat them immediately or

cache Cache, caching, or caché may refer to: Science and technology * Cache (computing), a technique used in computer storage for easier data access * Cache (biology) or hoarding, a food storing behavior of animals * Cache (archaeology), artifacts p ...

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 flowering plant, angiosperm or gymnosperm, the growth of a sporeling from a spore, such as the sp ...

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 that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

and

Baja California Baja California, officially the Free and Sovereign State of Baja California, is a state in Mexico. It is the northwesternmost of the 32 federal entities of Mexico. Before becoming a state in 1952, the area was known as the North Territory of B ...

. The

concept A concept is an abstract idea that serves as a foundation for more concrete principles, thoughts, and beliefs. Concepts play an important role in all aspects of cognition. As such, concepts are studied within such disciplines as linguistics, ...

of this species has gradually narrowed as

phylogenetic In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical dat ...

research and

taxonomic 280px, Generalized scheme of taxonomy Taxonomy is a practice and science concerned with classification or categorization. Typically, there are two parts to it: the development of an underlying scheme of classes (a taxonomy) and the allocation ...

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 international border separating Mexico and the United States extends from the Pacific Ocean in the west to the Gulf of Mexico in the east. The border traverses a variety of terrains, ranging from urban areas to deserts. It is the List of ...

south to the Colonet peninsula. It is threatened by

habitat loss Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...

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

chaparral Chaparral ( ) is a shrubland plant plant community, community found primarily in California, southern Oregon, and northern Baja California. It is shaped by a Mediterranean climate (mild wet winters and hot dry summers) and infrequent, high-intens ...

", in which Coastal sage scrub oak and

toyon ''Heteromeles arbutifolia'' (, more commonly by Californian botanists), commonly known as toyon, is a perennial shrub native to Coastal California. It is the sole species in the genus ''Heteromeles''. Description Toyon typically grows from , r ...

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 rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

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

wildfire A wildfire, forest fire, or a bushfire is an unplanned and uncontrolled fire in an area of Combustibility and flammability, combustible vegetation. Depending on the type of vegetation present, a wildfire may be more specifically identified as a ...

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 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 ceanothus. ''"Ceanothus" ...

'' 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 that are or were threatened by habitat loss Taxonomy articles created by Polbot Oaks of Mexico