Northern Pin Oak
Encyclopedia
Quercus ellipsoidalis, the Northern Pin Oak or Hill's Oak, is an oak
in the red oak section Quercus sect. Lobatae. It is mainly native to the northern midwest
United States
, and also in the southeast and southwest of Ontario
, Canada
. It occurs on dry, sandy, usually acid
ic soils. Although the name suggests an alliance to the Pin Oak
Q. palustris, it has traditionally been thought to be closely related to the Scarlet Oak
Q. coccinea, and was in fact included in that species by many botanists. However, recent work suggests that Hill's oak is more closely related to Black Oak Q. velutina and that there may be ongoing gene flow between those species (Hipp and Weber 2008). The morphological similarity between Q. ellipsoidalis and Q. coccinea remains a source of confusion, especially in northwestern Indiana and southern Cook County, Illinois.
It is a medium-sized deciduous
tree
growing to 20 m tall with an open, rounded crown. The leaves
are glossy green, 7-13 cm long and 5-10 cm broad, lobed, with five or seven lobes, and deep sinuses between the lobes. Each lobe has 3-7 bristle-tipped teeth. The leaf is nearly hairless, except for small tufts of pale orange-brown down where the lobe veins join the central vein. The acorn
s tend to be ellipsoid (ellipse
-shaped, from which its scientific name derives), though they tend to be highly variable and range to globose, 6-11 mm long and 10-19 mm broad, a third to a half covered in a deep cup, green maturing pale brown about 18 months after pollination
; the kernel is very bitter. The inner surface of the acorn cap is glabrous (hairless) to sparsely or moderately pubescent, and the hairs if present tend to be kinky rather than straight.
is too small to be of any importance, but is similar to that of other red oak
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...
in the red oak section Quercus sect. Lobatae. It is mainly native to the northern midwest
Midwestern United States
The Midwestern United States is one of the four U.S. geographic regions defined by the United States Census Bureau, providing an official definition of the American Midwest....
United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, and also in the southeast and southwest of Ontario
Ontario
Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
. It occurs on dry, sandy, usually acid
Acid
An acid is a substance which reacts with a base. Commonly, acids can be identified as tasting sour, reacting with metals such as calcium, and bases like sodium carbonate. Aqueous acids have a pH of less than 7, where an acid of lower pH is typically stronger, and turn blue litmus paper red...
ic soils. Although the name suggests an alliance to the Pin Oak
Pin oak
Quercus palustris, the Pin oak or Swamp Spanish oak, is an oak in the red oak section Quercus sect. Lobatae.-Distribution:...
Q. palustris, it has traditionally been thought to be closely related to the Scarlet Oak
Scarlet Oak
Quercus coccinea, the scarlet oak, is an oak in the red oak section Quercus sect. Lobatae. The scarlet oak can be mistaken for the pin oak, the black oak, or occasionally the red oak. On scarlet oak the sinuses between lobes are "C"-shaped in comparison to pin oak , which has "U"-shaped sinuses...
Q. coccinea, and was in fact included in that species by many botanists. However, recent work suggests that Hill's oak is more closely related to Black Oak Q. velutina and that there may be ongoing gene flow between those species (Hipp and Weber 2008). The morphological similarity between Q. ellipsoidalis and Q. coccinea remains a source of confusion, especially in northwestern Indiana and southern Cook County, Illinois.
It is a medium-sized deciduous
Deciduous
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 20 m tall with an open, rounded crown. 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 glossy green, 7-13 cm long and 5-10 cm broad, lobed, with five or seven lobes, and deep sinuses between the lobes. Each lobe has 3-7 bristle-tipped teeth. The leaf is nearly hairless, except for small tufts of pale orange-brown down where the lobe veins join the central vein. The 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 tend to be ellipsoid (ellipse
Ellipse
In geometry, an ellipse is a plane curve that results from the intersection of a cone by a plane in a way that produces a closed curve. Circles are special cases of ellipses, obtained when the cutting plane is orthogonal to the cone's axis...
-shaped, from which its scientific name derives), though they tend to be highly variable and range to globose, 6-11 mm long and 10-19 mm broad, a third to a half covered in a deep cup, green maturing pale brown about 18 months after pollination
Pollination
Pollination is the process by which pollen is transferred in plants, thereby enabling fertilisation and sexual reproduction. Pollen grains transport the male gametes to where the female gamete are contained within the carpel; in gymnosperms the pollen is directly applied to the ovule itself...
; the kernel is very bitter. The inner surface of the acorn cap is glabrous (hairless) to sparsely or moderately pubescent, and the hairs if present tend to be kinky rather than straight.
Uses
Northern Pin Oak is occasionally planted as an ornamental tree, popular for its bright red fall color and tolerance of infertile sandy soils. The woodWood
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...
is too small to be of any importance, but is similar to that of other red oak