Sawtooth Oak
Encyclopedia
Quercus acutissima, the Sawtooth Oak, is an oak
originally native to eastern Asia
, in China
, Korea
and Japan
. It is now also present in North America
. It is closely related to the Turkey Oak
, classified with it in Quercus sect. Cerris, a section of the genus characterised by shoot buds surrounded by soft bristles, bristle-tipped leaf lobes, and acorn
s that mature in about 18 months.
tree
growing to 25–30 m tall with a trunk up to 1.5 m diameter. The bark
is dark gray and deeply furrowed. The leaves
are 8–20 cm long and 3–6 cm wide, with 14-20 small saw-tooth like triangular lobes on each side, with the teeth of very regular shape.
The flower
s are wind-pollinated catkin
s. The fruit
is an acorn
, maturing about 18 months after pollination, 2–3 cm long and 2 cm broad, bicoloured with an orange basal half grading to a green-brown tip; the acorn cup is 1.5–2 cm deep, densely covered in soft 4–8 mm long 'mossy' bristles. It is closely related to the Turkey Oak
, classified with it in Quercus sect. Cerris, a section of the genus characterised by shoot buds surrounded by soft bristles, bristle-tipped leaf lobes, and acorn
s that mature in about 18 months.
s and pigeons; squirrel
s usually only eat them when other food sources have run out.
and is naturalised in some areas; it is also occasionally planted in Europe
but has not naturalised there. Most planting in North America was carried out for wildlife
food provision, as the species tends to bear heavier crops of acorns than other native American oak species; however the bitterness of the acorns makes it less suitable for this purpose and Sawtooth Oak is becoming a problem invasive species
in some areas. Sawtooth Oak trees also grow at a faster rate which helps it compete against other native trees. The wood
has many of the characteristics of other oaks, but is very prone to crack and split and hence is relegated to such uses as fencing.
Oak
An oak is a tree or shrub in the genus Quercus , of which about 600 species exist. "Oak" may also appear in the names of species in related genera, notably Lithocarpus...
originally native to eastern Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
, in China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
, Korea
Korea
Korea ) is an East Asian geographic region that is currently divided into two separate sovereign states — North Korea and South Korea. Located on the Korean Peninsula, Korea is bordered by the People's Republic of China to the northwest, Russia to the northeast, and is separated from Japan to the...
and Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
. It is now also present in North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
. It is closely related to the Turkey Oak
Turkey Oak
Quercus cerris, the Turkey oak is an oak native to southern Europe and Asia Minor. It is the type species of Quercus sect. Cerris, a section of the genus characterised by shoot buds surrounded by soft bristles, bristle-tipped leaf lobes, and acorns that usually mature in 18...
, classified with it in Quercus sect. Cerris, a section of the genus characterised by shoot buds surrounded by soft bristles, bristle-tipped leaf lobes, and acorn
Acorn
The acorn, or oak nut, is the nut of the oaks and their close relatives . It usually contains a single seed , enclosed in a tough, leathery shell, and borne in a cup-shaped cupule. Acorns vary from 1–6 cm long and 0.8–4 cm broad...
s that mature in about 18 months.
Description
It is a medium-sized deciduousDeciduous
Deciduous means "falling off at maturity" or "tending to fall off", and is typically used in reference to trees or shrubs that lose their leaves seasonally, and to the shedding of other plant structures such as petals after flowering or fruit when ripe...
tree
Tree
A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...
growing to 25–30 m tall with a trunk up to 1.5 m diameter. The bark
Bark
Bark is the outermost layers of stems and roots of woody plants. Plants with bark include trees, woody vines and shrubs. Bark refers to all the tissues outside of the vascular cambium and is a nontechnical term. It overlays the wood and consists of the inner bark and the outer bark. The inner...
is dark gray and deeply furrowed. The leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
are 8–20 cm long and 3–6 cm wide, with 14-20 small saw-tooth like triangular lobes on each side, with the teeth of very regular shape.
The flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s are wind-pollinated catkin
Catkin
A catkin or ament is a slim, cylindrical flower cluster, with inconspicuous or no petals, usually wind-pollinated but sometimes insect pollinated . They contain many, usually unisexual flowers, arranged closely along a central stem which is often drooping...
s. The fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
is an acorn
Acorn
The acorn, or oak nut, is the nut of the oaks and their close relatives . It usually contains a single seed , enclosed in a tough, leathery shell, and borne in a cup-shaped cupule. Acorns vary from 1–6 cm long and 0.8–4 cm broad...
, maturing about 18 months after pollination, 2–3 cm long and 2 cm broad, bicoloured with an orange basal half grading to a green-brown tip; the acorn cup is 1.5–2 cm deep, densely covered in soft 4–8 mm long 'mossy' bristles. It is closely related to the Turkey Oak
Turkey Oak
Quercus cerris, the Turkey oak is an oak native to southern Europe and Asia Minor. It is the type species of Quercus sect. Cerris, a section of the genus characterised by shoot buds surrounded by soft bristles, bristle-tipped leaf lobes, and acorns that usually mature in 18...
, classified with it in Quercus sect. Cerris, a section of the genus characterised by shoot buds surrounded by soft bristles, bristle-tipped leaf lobes, and acorn
Acorn
The acorn, or oak nut, is the nut of the oaks and their close relatives . It usually contains a single seed , enclosed in a tough, leathery shell, and borne in a cup-shaped cupule. Acorns vary from 1–6 cm long and 0.8–4 cm broad...
s that mature in about 18 months.
Taxonomy
Synonyms include: Quercus acutissima var. depressinucata H. W. Jen & R. Q. Gao; Q. acutissima var. septentrionalis Liou; Q. lunglingensis Hu.Distribution and habitat
Deciduous forests; below 100–2200 m. Anhui, Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hebei, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Liaoning, Shaanxi, Shandong, Shanxi, Sichuan, SE Xizang,Yunnan, Zhejiang Bhutan, Cambodia, NE India, Japan, Korea, Myanmar, Nepal, N Thailand, Vietnam.Ecology
The acorns are very bitter, but are eaten by jayJay
The jays are several species of medium-sized, usually colorful and noisy, passerine birds in the crow family Corvidae. The names jay and magpie are somewhat interchangeable, and the evolutionary relationships are rather complex...
s and pigeons; squirrel
Squirrel
Squirrels belong to a large family of small or medium-sized rodents called the Sciuridae. The family includes tree squirrels, ground squirrels, chipmunks, marmots , flying squirrels, and prairie dogs. Squirrels are indigenous to the Americas, Eurasia, and Africa and have been introduced to Australia...
s usually only eat them when other food sources have run out.
Uses
Sawtooth Oak is widely planted in eastern North AmericaNorth America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
and is naturalised in some areas; it is also occasionally planted in Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
but has not naturalised there. Most planting in North America was carried out for wildlife
Wildlife
Wildlife includes all non-domesticated plants, animals and other organisms. Domesticating wild plant and animal species for human benefit has occurred many times all over the planet, and has a major impact on the environment, both positive and negative....
food provision, as the species tends to bear heavier crops of acorns than other native American oak species; however the bitterness of the acorns makes it less suitable for this purpose and Sawtooth Oak is becoming a problem invasive species
Invasive species
"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
in some areas. Sawtooth Oak trees also grow at a faster rate which helps it compete against other native trees. The wood
Wood
Wood is a hard, fibrous tissue found in many trees. It has been used for hundreds of thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers embedded in a matrix of lignin which resists compression...
has many of the characteristics of other oaks, but is very prone to crack and split and hence is relegated to such uses as fencing.