10/09/2019

Northern Red Oak

Quercus rubra

The Ohio Chapter ISA continued efforts is to advance responsible tree care practices through research, technology, and education while promoting the benefits of trees. This month Tree-Of-The-Month is the Northern Red Oak (Quercus rubra). The Northern Red Oak can grow 50-70 feet tall as wide and in some cases larger if placed in optimal site conditions. The Northern Red Oak is a medium-sized, deciduous tree with a rounded to broad-spreading, often irregular crown. Northern Red Oak grows at a moderate-to-fast rate. The Northern Red Oak has handsome dark, lustrous green leaves (grayish-white beneath) with 7-11, toothed lobes which are sharply pointed at the tips. Leaves of the Northern Red Oak will turn brownish-red in autumn. This Oak has insignificant flowers in separate male and female catkins that appear in spring. Fruits of the Northern Red Oak are acorns (with flat, saucer-shaped cups) which mature in early fall. An abundant crop of acorns may not occur before this tree reaches 40 years old. It is also known as Northern Red Oak (since there is also a Southern Red Oak of the southern United States) and may be found cited in older literature by its previous scientific name of Quercus borealis.

Northern Red Oak prefers moist, deep, fertile, well-drained soils of slightly acidic pH. It adapts readily to dry soils of acidic, neutral, or slightly alkaline pH (it will develop chlorosis in high pH soils). Chlorosis (yellowing of the leaves while the veins remain green) often occurs when soils are not sufficiently acidic. It thrives in full sun to partial sun (but is shade tolerant in youth) and is found in zones 3 to 7. Generally a durable and long-lived tree. Northern red oak grows on a variety of dry-mesic to mesic sites like rich, mesic woods, on sandy plains, rocky outcrops, stable interdunes, and at the outer edges of floodplain

The Northern Red Oak is a native Ohio tree which typically occurs in northern- and eastern-facing wooded slopes throughout the State. The Northern Red Oak is an important source of hardwood lumber. The wood is close-grained, heavy, and hard; it machines well and accepts a variety of finishes. It is used for furniture, veneer, interior finishing, cabinets, paneling, and flooring as well as for agricultural implements, posts, and railway ties.

Northern Red Oak belongs to the Genus of plants known as Beech Family (Fagaceae). The Genus name(Quercus) comes from the classical Latin name for oak trees, while the species epithet means red. The Northern Red Oak tree provides excellent cover and nesting sites (including cavities) for a wide variety of birds and mammals. Deer, elk, moose, and rabbits commonly browse leaves, and young seedlings and the acorns are eaten by a wide variety of large and small mammals and birds.

Ethnobotanical Information

The acorns of Northern Red Oak (and other oak species) were an important food source for Native Americans. To remove bitter tannins, they were boiled, leached with ashes, soaked for days in water, or buried over winter. Some tribes used red oak bark as a medicine for heart troubles and bronchial infections or as an astringent, disinfectant, and cleanser.

Variation within the species: There are different interpretations of variation patterns among trees of Northern Red Oak. A single species is without formally variations is sometimes recognized, or two varieties may be recognized.

Oak wilt

Northern red oak is susceptible to oak wilt, a fungal disease that invades the water-conducting vessels and plugs them. As water movement is slowed, the leaves wilt and rapidly drop off the tree. The disease begins with a crinkling and paling of the leaves, followed by wilting and browning from the margins inward. Necrosis may be strongest along the veins or between them. The symptoms move down branches toward the center of the tree, and the tree may die within 1–3 months, although some diseased trees may survive up to a year. The disease may be spread by insects (primarily beetles) or pruning tools, but most of the tree loss in oak wilt centers results from transmission through root spread between adjoining trees.

Special Note: Prune oaks in the dormant season to avoid attracting beetles that may carry oak wilt.

Tree Selection Tips
The Ohio Chapter ISA recommends working with an ISA Certified Arborist when selecting or caring for any tree in your landscape. To better guide you on the vital plant information for the Red Buds use our friendly users guide below:

Written by Mark A. Webber BCMA, CPH, LTE,  MArborA, OCMNT, TRAQ

Sources:

http://forestry.ohiodnr.gov/redoak

https://plants.usda.gov/plantguide/pdf/cs_quru.pdf

https://www.mortonarb.org/trees-plants/tree-plant-descriptions/northern-red-oak

Photograph sources Mark A. Webber 2019