''Quercus kelloggii'', the California black oak, also known as Kellogg oak, is an oak in the red oak section (genus ''Quercus'', section ''Lobatae'', series ''Agrifoliae''), native to western North America. Although genetically separated from them for more than 20 million years, its leaves (though not its fruit) are remarkably similar in appearance to several other members of the red oak section including the red oak (''

Quercus rubra ''Quercus rubra'', the northern red oak, is an oak tree in the red oak group (''Quercus'' section ''Lobatae''). It is a native of North America, in the eastern and central United States and southeast and south-central Canada. It has been intro ...

'') and the black oak (''

Quercus velutina ''Quercus velutina'', the black oak, is a species of oak in the red oak group (''Quercus'' sect. ''Lobatae''), native and widespread in eastern and central North America. It is sometimes called the eastern black oak. ''Quercus velutina'' was p ...

'') found in eastern and central North America.

Description

''Quercus kelloggii'' typically grows from in height and from in diameter. Large trees may exceed in height and diameter, with the record holder measuring tall and thick (in the Siskiyou National Forest in

Oregon Oregon () is a U.S. state, state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington (state), Washington, while the Snake River delineates much of it ...

). The species also grows in

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 tree ...

by scrub-oak form on poor sites. In open areas, the crown is broad and rounded, with lower branches nearly touching the ground or forming a browse line. In closed stands, the crown is narrow and slender in young trees and irregularly broad in old trees. Trunks are usually free of branches on the lower in closed stands. Trunks are often forked, and usually decayed and hollow in older trees. The

bark Bark may refer to: * Bark (botany), an outer layer of a woody plant such as a tree or stick * Bark (sound), a vocalization of some animals (which is commonly the dog) Places * Bark, Germany * Bark, Warmian-Masurian Voivodeship, Poland Arts, e ...

is thin and smooth in young trees, becoming thick, ridged, plate-like, and blackish with age. This oak grows from one to several vertical roots which penetrate to bedrock, with large, laterally spreading roots extending off from vertical ones. It also has a number of surface roots.

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 b ...

s are relatively large in this species, from long and wide. The

leaves A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, st ...

are typically long and deeply lobed, usually into seven portions; they are red and velvety when young, turning yellow-green then orange-brown in autumn. While individual trees generally have a lifespan between 100 and 200 years, California black oak can live up to 500 years. The tree reproduces when its acorns sprout to form seedlings. It also reproduces

vegetatively Vegetative reproduction (also known as vegetative propagation, vegetative multiplication or cloning) is any form of asexual reproduction occurring in plants in which a new plant grows from a fragment or cutting of the parent plant or speci ...

with new growth sprouting from the root crown after the tree is top-killed by

wildfire A wildfire, forest fire, bushfire, wildland fire or rural fire is an unplanned, uncontrolled and unpredictable fire in an area of combustible vegetation. Depending on the type of vegetation present, a wildfire may be more specifically identi ...

logging Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidding, on-site processing, and loading of trees or logs onto trucks or skeleton cars. Logging is the beginning of a supply cha ...

frost Frost is a thin layer of ice on a solid surface, which forms from water vapor in an above-freezing atmosphere coming in contact with a solid surface whose temperature is below freezing, and resulting in a phase change from water vapor (a g ...

, or other events.

Distribution and habitat

California black oak is a

deciduous In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, ...

tree growing in mixed evergreen forests, oak woodlands, and

conifer Conifers are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All ext ...

ous forests. California black oak is distributed along foothills and lower mountains of

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

and western Oregon. It can be found at altitudes of up to , for example near

Mount Shasta Mount Shasta ( Shasta: ''Waka-nunee-Tuki-wuki''; Karuk: ''Úytaahkoo'') is a potentially active volcano at the southern end of the Cascade Range in Siskiyou County, California. At an elevation of , it is the second-highest peak in the Cascad ...

. It is found from

Lane County, Oregon Lane County is one of the 36 counties in the U.S. state of Oregon. As of the 2020 census, the population was 382,971, making it the fourth-most populous county in Oregon. The county seat is Eugene. It is named in honor of Joseph Lane, Ore ...

, south through the

Cascade Range The Cascade Range or Cascades is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as the North Cascades, ...

, the

Sierra Nevada The Sierra Nevada () is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primar ...

, and the

Coast The coast, also known as the coastline or seashore, is defined as the area where land meets the ocean, or as a line that forms the boundary between the land and the coastline. The Earth has around of coastline. Coasts are important zones in n ...

Transverse Transverse may refer to: *Transverse engine, an engine in which the crankshaft is oriented side-to-side relative to the wheels of the vehicle * Transverse flute, a flute that is held horizontally * Transverse force (or ''Euler force''), the tange ...

, and

Peninsular Ranges The Peninsular Ranges (also called the Lower California province) are a group of mountain ranges that stretch from Southern California to the southern tip of the Baja California peninsula; they are part of the North American Coast Ranges, which ...

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 f ...

. The tree occurs in pure or mixed stands. Pure stands usually indicate sites unfavorable to conifer growth or recurring disturbance such as fire or logging activities. The tree can grow in many types of soils, but they must be well-drained.

Ecology

The California black oak is a critical species for

wildlife Wildlife refers to undomesticated animal species, but has come to include all organisms that grow or live wild in an area without being introduced by humans. Wildlife was also synonymous to game: those birds and mammals that were hunted ...

. Oaks (''Quercus'' spp.) may be the single most important genus used by wildlife for food and cover in California forests and rangelands, and California black oak occupies more total area in California than any other hardwood species. Livestock also make heavy use of this species for food and cover. Older trees affected by heart rot have cavities which provide den or nest sites for owls, various

woodpecker Woodpeckers are part of the bird family Picidae, which also includes the piculets, wrynecks, and sapsuckers. Members of this family are found worldwide, except for Australia, New Guinea, New Zealand, Madagascar, and the extreme polar regions ...

tree squirrel Tree squirrels are the members of the squirrel family (Sciuridae) commonly just referred to as "squirrels." They include more than 100 arboreal species native to all continents except Antarctica and Oceania. They do not form a single natural, o ...

s, and

American black bear The American black bear (''Ursus americanus''), also called simply a black bear or sometimes a baribal, is a medium-sized bear endemic to North America. It is the continent's smallest and most widely distributed bear species. American black bear ...

s. Trees provide valuable shade for livestock and wildlife during the hot summer. California black oak forest types are heavily used for spring, summer, and fall cover by black bears. It is browsed by

deer Deer or true deer are hoofed ruminant mammals forming the family Cervidae. The two main groups of deer are the Cervinae, including the muntjac, the elk (wapiti), the red deer, and the fallow deer; and the Capreolinae, including the re ...

and livestock. Acorns are heavily used by livestock, mule deer, feral pigs, rodents,

mountain quail The mountain quail (''Oreortyx pictus'') is a small ground-dwelling bird in the New World quail family. This species is the only one in the genus ''Oreortyx'', which is sometimes included in '' Callipepla''. This is not appropriate, however, as ...

Steller's jay Steller's jay (''Cyanocitta stelleri'') is a bird native to western North America and the mountains of Central America, closely related to the blue jay found in eastern North America. It is also known as the long-crested jay, mountain jay, and p ...

s, and woodpeckers. Acorns constitute an average of 50% of the fall and winter diets of western gray squirrels and black-tailed deer during good mast years. Fawn survival rates increase or decrease with the size of the acorn crop. It is a preferred foraging substrate for many birds. All of 68 bird species observed in oak woodlands of the

Tehachapi Mountains The Tehachapi Mountains (; Kawaiisu: ''Tihachipia'', meaning "hard climb") are a mountain range in the Transverse Ranges system of California in the Western United States. The range extends for approximately in southern Kern County and northwe ...

of California used California black oak for part of their foraging activities. Acorn woodpecker, Bullock's oriole, and Nashville warbler show strong preferences for California black oak. The

parasitic plant A parasitic plant is a plant that derives some or all of its nutritional requirements from another living plant. They make up about 1% of angiosperms and are found in almost every biome. All parasitic plants develop a specialized organ called th ...

Pacific mistletoe (''Phoradendron villosum''), which commonly grows on this oak, produces berries that attract birds, as well. Many animals cache the acorns, and acorns that have been stored in the ground or otherwise buried are more likely to sprout than those that remain on the surface. The tree is adapted to wildfire. It is protected from smaller fires by its thick bark. If it is top-killed and burned away in a larger fire, it easily resprouts and has a good supply of nutrients and water stored in its root system. Acorns sprout into seedlings after fire, and sites that have been cleared of canopy and leaf litter in fires are ideal for seedling success. The tree is less

shade tolerant In ecology, shade tolerance is a plant's ability to tolerate low light levels. The term is also used in horticulture and landscaping, although in this context its use is sometimes imprecise, especially in labeling of plants for sale in commercial ...

than its associate

ponderosa pine ''Pinus ponderosa'', commonly known as the ponderosa pine, bull pine, blackjack pine, western yellow-pine, or filipinus pine is a very large pine tree species of variable habitat native to mountainous regions of western North America. It is the ...

. It is vulnerable to sudden oak death.

Allergenicity

The pollen is released in spring and is a severe allergen.

Uses

Some California Native Americans prefer California black oak acorns over those of other species for making acorn meal. Historically, this acorn was a

staple food A staple food, food staple, or simply a staple, is a food that is eaten often and in such quantities that it constitutes a dominant portion of a standard Diet (nutrition), diet for a given person or group of people, supplying a large fraction of ...

for many Native American groups,Ethnobotany
/ref> who usually leached out the bitter

tannin Tannins (or tannoids) are a class of astringent, polyphenolic biomolecules that bind to and precipitate proteins and various other organic compounds including amino acids and alkaloids. The term ''tannin'' (from Anglo-Norman ''tanner'' ...

. Native Americans recognized the importance of fire to this oak, and purposely lit fires in oak woodlands to promote its health and ensure their food source. The

wood Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin ...

is used for making furniture,

pallet A pallet (also called a skid) is a flat transport structure, which supports goods in a stable fashion while being lifted by a forklift, a pallet jack, a front loader, a jacking device, or an erect crane. A pallet is the structural founda ...

s, and construction timber. The tree is used as an ornamental.

Timber

California black oak comprises a total volume of 29% of California's hardwood timber resources, and is the major hardwood sawn into lumber there. The total estimated area of species occurrence is 361,800 hectares (3,618 square kilometers or 894,000 acres); 239,200 ha (2,392 km² or 591,000 acres) of timberland and 122,600 ha (1,226 km² or 303,000 acres) of woodland. Of this land 60% is privately owned, 31% is in National Forests, and 9% is on other public lands. It has greatly decreased from its historic abundance. This is due to a number of factors, including drought, disease, animal foraging, logging practices, fire suppression, and a variety of other human impacts. Cutting green trees for fuelwood has contributed to the decline of this species, and illegal harvesting of green trees from public lands is a continuing problem. It was long considered by foresters and government agencies to be a weed tree. In its earlier years, its only use to settlers was to feed the boilers of donkey engines bringing in the valuable pine and fir logs. For a period in the mid-1960s, the U.S. Forest Service policy in California's National Forests was systematic extermination of California black oak by girdling the trees. The objective was to make room for more coniferous growth. In the rush to use the pines, firs, and redwoods, the dense hardwoods were looked on with contempt. Like a few other visionaries in the 1960s, Guy Hall thought the California black oak presented a beautiful challenge that deserved better than eradication. In 1965, Hall convinced federal agencies to cease their extermination policies.

Plantation A plantation is an agricultural estate, generally centered on a plantation house, meant for farming that specializes in cash crops, usually mainly planted with a single crop, with perhaps ancillary areas for vegetables for eating and so on. Th ...

s of California black oak have been successfully established in clearcuts from acorn plantings. Thinning such stands promotes stand productivity and wood quality, and is recommended when trees are from tall or when stand density (basal area) exceeds 29 m²/ha (125 ft²/acre). This tree has also been managed for hardwood production by maintaining scattered pure stands within coniferous forests. Stands of this species often establish on poorer sites, where conifer seedling establishment has not been successful.

Cultivation

''Q. kelloggii'' is cultivated in the specialty

horticulture Horticulture is the branch of agriculture that deals with the art, science, technology, and business of plant cultivation. It includes the cultivation of fruits, vegetables, nuts, seeds, herbs, sprouts, mushrooms, algae, flowers, seaweeds and no ...

trade as an ornamental tree for

native plant In biogeography, a native species is indigenous to a given region or ecosystem if its presence in that region is the result of only local natural evolution (though often popularised as "with no human intervention") during history. The term is eq ...

drought-tolerant Drought tolerance is the ability to which a plant maintains its biomass production during arid or drought conditions. Some plants are naturally adapted to dry conditions'','' surviving with protection mechanisms such as desiccation tolerance, detox ...

, water-conserving, and

habitat garden A wildlife garden (or wild garden) is an environment created by a gardener that serves as a sustainable haven for surrounding wildlife. Wildlife gardens contain a variety of habitats that cater to native and local plants, birds, amphibians, rep ...

s, and various types of municipal, commercial, and agency sustainable landscape and restoration projects.

References

External links

*
Nupa (Black Oak Acorn) Soup recipe
— ''from Tuolumne Rancheria''. *
Interactive Map of ''Quercus kelloggii'' Range
* Beckman, E. 2016
''Quercus kelloggii''.
The IUCN Red List of Threatened Species 2016. Downloaded on 19 July 2017. {{Taxonbar, from=Q693392 kelloggii Flora of the West Coast of the United States Natural history of the California chaparral and woodlands Natural history of the California Coast Ranges Natural history of the Peninsular Ranges Plants described in 1859 Natural history of the San Francisco Bay Area Natural history of the Santa Monica Mountains Natural history of the Transverse Ranges Trees of Mediterranean climate Garden plants of North America Ornamental trees Drought-tolerant trees