Quercus rubra

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Quercus rubra
Quercus rubra @ Tortworth Court.jpg
Northern red oak in autumn
Status TNC G5.svg
Secure  (NatureServe) [2]
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Fagales
Family: Fagaceae
Genus: Quercus
Subgenus: Quercus subg. Quercus
Section: Quercus sect. Lobatae
Species:
Q. rubra
Binomial name
Quercus rubra
L.
Quercus rubra range map 1.png
Synonyms
  • Erythrobalanus rubra(L.) O.Schwarz
  • Quercus ambiguaF.Michx.
  • Quercus angulizanaRaf.
  • Quercus borealisF.Michx.
  • Quercus cuneataDippel
  • Quercus maxima(Marshall) Ashe
  • Quercus sadaMast.

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 introduced to small areas in Western Europe, where it can frequently be seen cultivated in gardens and parks. It prefers good soil that is slightly acidic. Often simply called red oak, northern red oak is so named to distinguish it from southern red oak (Q. falcata), also known as the Spanish oak. Northern Red Oak is sometimes called champion oak.

Contents

Description

In many forests, Quercus rubra grows straight and tall, to 28 metres (92 feet), exceptionally to 43 m (141 ft) tall, with a trunk of up to 50–100 centimetres (20–39 inches) in diameter. Open-grown trees do not get as tall, but can develop a stouter trunk, up to 2 m (6+12 ft) in diameter. It has stout branches growing at right angles to the stem, forming a narrow round-topped head. [3]

Under optimal conditions and full sun, northern red oak is fast growing and a 10-year-old tree can be 5–6 m (16–20 ft) tall. [4] Trees may live up to 400 years; [5] a living example of 326 years was noted in 2001. [6] [7]

Northern red oak is easy to recognize by its bark, which features ridges that appear to have shiny stripes down the center. A few other oaks have bark with this kind of appearance in the upper tree, but the northern red oak is the only tree with the striping all the way down the trunk. [6]

As with most other deciduous oaks, leafout takes place in spring when day length has reached 13 hours—it is tied entirely to photoperiod and will take place regardless of air temperature. As a consequence (see below), in cooler regions, northern red oaks often lose their flowers to late spring frosts, resulting in no seed crop for the year. The catkins and leaves emerge at the same time. The acorns develop on the tree for two growing seasons and are released from the tree in early October, and leaf drop begins when day length falls under 11 hours. The timing of leafout and leaf drop can vary by as much as three weeks in the northern and southern US. Seedlings emerge in spring when soil temperatures reach 21 °C (70 °F).[ citation needed ]

Red oak acorns, unlike the white oak group, display epigeal dormancy and will not germinate without a minimum of three months' exposure to temperatures below 4 °C (40 °F). They also take two years of growing on the tree before development is completed. [6]

Distribution and habitat

The species grows from the north end of the Great Lakes, east to Nova Scotia, south as far as Georgia, Mississippi, Alabama, and Louisiana, and west to Oklahoma, Kansas, Nebraska, and Minnesota. [8]

It grows rapidly and is tolerant of many soils and varied situations, although it prefers the glacial drift and well-drained borders of streams. [3] In the southeastern United States, it is frequently a part of the canopy in an oak-heath forest, but generally not as important as some other oaks. [9] [10] [6]

Northern red oak is the most common species of oak in the northeastern US after the closely related pin oak (Q. palustris). The red oak group as a whole are more abundant today than they were when European settlement of North America began as forest clearing and exploitation for lumber much reduced the population of the formerly dominant white oaks.[ citation needed ]

Reproduction

“Northern red oak (Quercus rubraL.) is monoecious, dichogamous, wind-pollinated, and self-incompatible”. [11] Pollination occurs in the first growing season, but fertilization and acorn maturation occur during the second growing season. [12]

Ecology

Mossy trunk of a large, old-growth individual surrounded by hemlocks within the Jakey Hollow Natural Area of Weiser State Forest in Columbia County, Pennsylvania Jakey Hollow Natural Area (Revisit) (27) (17008356190).jpg
Mossy trunk of a large, old-growth individual surrounded by hemlocks within the Jakey Hollow Natural Area of Weiser State Forest in Columbia County, Pennsylvania

Over the last few decades, the northern red oak has dealt with several environmental factors, mainly disease, predation by insects, and limited opportunities for dispersal. These stresses have impacted the species' ability to proliferate in both the Northeast and Europe. [13] The various environmental responses observed in Quercus rubra across several temperate environmental conditions have allowed for it to serve as a model organism for studying symbiotic relationships, dispersal, and habituation between tree species.

Pests and diseases

Canker pathogen, Diplodia corticola, has become a major pathogen to the species over the last decade, causing leaf browning, bark cracking and bleeding, and high rates of tree mortality across the northeastern United States. [14] The northern red oak is also characterized as one of the most susceptible species to plant fungi Phytophthora cinnamomi and Phytophthora ramorum, which have caused severe, red-black cankers in the trunk region of the species. [15] [16] [17] Both P. cinnamomi and P. ramorum grow under warmer temperature conditions; as a result, northern red oak trees found in California, France, and northern Spain all have a higher incidence of fungal infection. [17] [18] Oak Wilt caused by the fungus Bretziella fagacearum is a major pathogen found in eastern North America that can kill trees quickly. [19]

There has been a recent northern red oak decline in Arkansas which is “unique in that it is associated with increases in red oak borer” (Enaphalodes rufulus) which “is native to the eastern United States and usually occurs in mixed oak forests”. “It damages the phloem, sapwood, and heartwood which means the ability for growth and repair is attacked as well as the stability of the tree”. [20]

Abiotic stresses

Northern red oak seedlings have been known to have a high mortality rate in northeast regions prone to spring freeze, particularly in Massachusetts. Acorns produced by oaks in this region are typically smaller in size as an adaptation to frost produced in high latitudes; however, the resulting smaller seedlings have produced limited opportunities for animal consumption and dispersal. [21] Flooding along the continental United States has been shown to be a major issue for the northern red oak, in which decreased phloem transport and photosynthetic activity has been observed, but only after multiple days of flooding, indicating that the northern red oak has adapted moderate resistance to excess water exposure. [22] The northern red oak has also developed tolerance mechanisms for heat stress, particularly observed in deciduous forests in the Southeastern United States, where, during summer heat waves, temperatures can exceed 40 °C (104 °F). The leaves of the northern red oak have been observed to have an acclimation to Rubisco activase activity that is directly correlated to acclimations with repeated exposure to heat waves. Consistent photosynthetic activity in the red oak has also been observed in the presence of high carbon dioxide levels that often occur as a result of elevated temperatures. [23] [24]

Animals

Northern red oak kernels have highly concentrated amounts of bitter-tasting tannin, a biochemical classified as a predator deterrent, which has limited appeal for consumption among animals. Despite this, the acorns are eaten by deer, squirrels and birds. [6] In Europe, the acorns are consumed by several moth species, particularly Cydia fagiglandana and Cydia splendana , which increases their niche breadths and reduces their competition with Curculio weevils. [25] Due to this, germination rates among the northern red oak acorns have decreased significantly and resulted in less seed dispersal by animals within Poland. In addition, limited opportunities for dispersal have become costly for the northern red oak in Europe. European animals known for dispersing tendencies, such as the European jay and wood mouse, have been found to be more attracted to local oak species. [26]

Fungi

Quercus rubra has effective ectomycorrhizal relationships that have been correlated with increased growth rates. Northern red oak trees have been shown to increase growth in the presence of various ascomycetes that coil at the base of the oak trunk. The fungi, which eventually proliferate at the stumps of deciduous trees, have been found to be host-specific to both Quercus rubra and Quercus montana [27] and primarily promote growth upon infection. [27]

Invasiveness in Europe

It was introduced to Europe in the 1700s and has naturalized throughout most of western and central Europe. [28] Across western and central Europe, the northern red oak has become the fourth-most significant invasive species, colonizing several regions across Belgium, Germany, Northern Italy, Lithuania, Poland, Ukraine, European Russia, [29] the Urals and Western Siberia). The northern red oak is primarily found on the edges of woodland reserves in Europe, where light availability, tannin concentration, and animal dispersal are the most necessary component for the species' longevity and survival. [30] The high influx of the species in Europe is primarily based on its economic productivity as a fast-growing source of timber; however, it has been linked to lower percentages of trace elements and minerals found in the surrounding soil and reduced richness among native oak species such as Quercus robur . [31] [30] [32]

Uses

Wood; from Romeyn Beck Hough's fourteen-volume work The American Woods Quercusrubra.jpg
Wood; from Romeyn Beck Hough's fourteen-volume work The American Woods

The northern red oak is one of the most important oaks for timber production in North America. Quality red oak is of high value as lumber and veneer, while defective logs are used as firewood. Other related oaks are also cut and marketed as red oak, although their wood is not always of as high a quality. These include eastern black oak, scarlet oak, pin oak, Shumard oak, southern red oak and other species in the red oak group. Construction uses include flooring, veneer, interior trim, and furniture. It is also used for lumber, railroad ties, and fence posts.[ citation needed ]

Red oak wood grain is so open that smoke can be blown through it from end-grain to end-grain on a flat-sawn board. For this reason, it is subject to moisture infiltration and is unsuitable for outdoor uses such as boatbuilding or exterior trim.[ citation needed ]

The acorns can be collected in autumn, shelled, tied up in a cloth, and leached to remove bitterness. They can then be eaten whole or ground into meal. [33]

Ornamental use

Quercus rubra is grown in parks and large gardens as a specimen tree. [34] It is not planted as often as the closely related pin oak as it develops a taproot and quickly becomes difficult to transplant, however modern growing pots have made starting seedlings with taproots easier than in the past.

Culture

It is the state tree of New Jersey and the provincial tree of Prince Edward Island.

Famous specimens

The Shera-Blair red oak Quercus rubra with arborist.jpg
The Shera-Blair red oak

Related Research Articles

<span class="mw-page-title-main">Oak</span> Tree or shrub in the genus Quercus

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 in a cup. The genus is widely distributed in the Northern Hemisphere; it includes some 500 species, both deciduous and evergreen. Fossil oaks date back to the Middle Eocene. Molecular phylogeny shows that the genus is divided into Old World and New World clades, but many oak species hybridise freely, making the genus's history difficult to resolve.

<i>Quercus kelloggii</i> Species of oak tree

Quercus kelloggii, the California black oak or Kellogg oak, is an oak in the red oak section native to western North America. Although genetically separated from them for more than 20 million years, its leaves are remarkably similar in appearance to several other members of the red oak section including the red oak and the black oak found in eastern and central North America.

<i>Quercus alba</i> Species of oak tree

Quercus alba, the white oak, is one of the preeminent hardwoods of eastern and central North America. It is a long-lived oak, native to eastern and central North America and found from Minnesota, Ontario, Quebec, and southern Maine south as far as northern Florida and eastern Texas. Specimens have been documented to be over 450 years old.

<i>Quercus palustris</i> Species of oak tree

Quercus palustris, also called pin oak, swamp oak, or Spanish oak, is a tree in the red oak section of the genus Quercus. Pin oak is one of the most commonly used landscaping oaks in its native range due to its ease of transplant, relatively fast growth, and pollution tolerance.

<i>Quercus velutina</i> Species of oak tree

Quercus velutina, the black oak, is a species of oak in the red oak group, native and widespread in eastern and central North America. It is sometimes called the eastern black oak.

<i>Quercus robur</i> Species of flowering plant in the beech and oak family Fagaceae

Quercus robur, the pedunculate oak, is a species of flowering plant in the beech and oak family, Fagaceae. It is a large tree, native to most of Europe and western Asia, and is widely cultivated in other temperate regions. It grows on soils of near neutral acidity in the lowlands and is notable for its value to natural ecosystems, supporting a very wide diversity of herbivorous insects and other pests, predators and pathogens.

<i>Quercus suber</i> Species of plant

Quercus suber, commonly called the cork oak, is a medium-sized, evergreen oak tree in the section Quercus sect. Cerris. It is the primary source of cork for wine bottle stoppers and other uses, such as cork flooring and as the cores of cricket balls. It is native to southwest Europe and northwest Africa. In the Mediterranean basin the tree is an ancient species with fossil remnants dating back to the Tertiary period.

<i>Quercus virginiana</i> Species of oak tree

Quercus virginiana, also known as the southern live oak, is an evergreen oak tree endemic to the Southeastern United States. Though many other species are loosely called live oak, the southern live oak is particularly iconic of the Old South. Many very large and old specimens of live oak can be found today in the Deep South region of the United States.

<i>Quercus agrifolia</i> Evergreen oak tree native to California

Quercus agrifolia, the California live oak, or coast live oak, is a highly variable, often evergreen oak tree, a type of live oak, native to the California Floristic Province. It may be shrubby, depending on age and growing location, but is generally a medium-sized tree. It grows west of the Sierra Nevada mountain range from Mendocino County, California, south to northern Baja California in Mexico. It is classified in the red oak section of oaks.

<i>Quercus laurifolia</i> Species of oak tree

Quercus laurifolia is a medium-sized semi-evergreen oak in the red oak section Quercus sect. Lobatae. It is native to the southeastern and south-central the United States.

<i>Quercus douglasii</i> Species of oak tree

Quercus douglasii, known as blue oak, is a species of oak endemic to California, common in the Coast Ranges and the foothills of the Sierra Nevada. It is California's most drought-tolerant deciduous oak, and is a dominant species in the blue oak woodland ecosystem. It is occasionally known as mountain oak and iron oak.

<i>Quercus falcata</i> Species of oak tree

Quercus falcata, also called southern red oak, spanish oak, bottomland red oak or three-lobed red oak is an oak. Native to the southeastern United States, it gets its name the "Spanish Oak" as these are the areas of early Spanish colonies, whilst "southern red oak" comes from both its range and leaf color during late summer and fall. The southern red oak is a deciduous angiosperm, so has leaves that die after each growing period and come back in the next period of growth.

<i>Quercus coccinea</i> Species of oak tree

Quercus coccinea, the scarlet oak, is a deciduous tree in the red oak section Lobatae of the genus Quercus, in the family Fagaceae.

<i>Quercus lobata</i> Species of oak tree

Quercus lobata, commonly called the valley oak or roble, grows into the largest of California oaks. It is endemic to California, growing in interior valleys and foothills from Siskiyou County to San Diego County. Mature specimens may attain an age of up to 600 years. This deciduous oak requires year-round access to groundwater.

<i>Quercus castaneifolia</i> Species of oak tree

Quercus castaneifolia, the chestnut-leaved oak, is a species of oak in the turkey oak section Quercus sect. Cerris. It is native to the Caucasus and Alborz mountains of Iran, and resembles the closely related Turkey Oak in appearance.

<i>Quercus chrysolepis</i> Species of oak tree

Quercus chrysolepis, commonly termed canyon live oak, canyon oak, golden cup oak or maul oak, is a North American species of evergreen oak that is found in Mexico and in the western United States, notably in the California Coast Ranges. This tree is often found near creeks and drainage swales growing in moist cool microhabitats. Its leaves are a glossy dark green on the upper surface with prominent spines; a further identification arises from the leaves of canyon live oak being geometrically flat.

<i>Quercus pagoda</i> Species of oak tree

Quercus pagoda, the cherrybark oak, is one of the most highly valued red oaks in the southern United States. It is larger and better formed than southern red oak and commonly grows on more moist sites. Its strong wood and straight form make it an excellent timber tree. Many wildlife species use its acorns as food, and cherrybark oak makes a fine shade tree. Cherrybark oak was formerly considered to be a subspecies of southern red oak, Quercus falcata, subsp pagodifolia.

<i>Quercus rotundifolia</i> Species of flowering plant in the family Fagaceae

Quercus rotundifolia, the holm oak or ballota oak, is an evergreen oak native to the western Mediterranean region, with the majority on the Iberian Peninsula and minor populations in Northwest Africa. The species was first described by Jean-Baptiste Lamarck in 1785. It is the typical species of the Iberian dehesa or montado, where its sweet-astringent acorns are a source of food for livestock, particularly the Iberian pig. Its acorns have been used for human nourishment since the Neolithic era. It is placed in section Ilex. Some authors described it as a subspecies of Quercus ilex.

<i>Notholithocarpus</i> Species of flowering plant in the family Fagaceae

Notholithocarpus densiflorus, commonly known as the tanoak or tanbark-oak, is a broadleaf tree in the family Fagaceae, and the type species of the genus Notholithocarpus. It is native to the far western United States, particularly Oregon and California. It ranges from 15–40 meters in height, with a trunk diameter of 60–190 centimeters.

<i>Quercus pyrenaica</i> Species of oak tree

Quercus pyrenaica, also known as Pyrenean oak, or Spanish oak is a tree native to southwestern Europe and northwestern North Africa. Despite its common name, it is rarely found in the Pyrenees Mountains and is more abundant in northern Portugal and north and northwestern Spain.

References

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