Northern Red Oak State Tree of New Jersey

The state tree of New Jersey is the Northern Red Oak (Quercus rubra). This north American native tree is also known as red oak, common red oak, gray oak, eastern red oak, and mountain red oak. Red oak is deciduous and is found growing in the wild throughout the central and eastern regions of the United States. Red oak is hardy to Zone 3.

Red Oak is considered fast growing among the generally slow growing oak family. Red oak can reach 98 feet in height and 2 to 3 feet in diameter. Trees growing in ideal conditions have been known to achieve 160 feet in height and 8 feet in diameter. The red oak trunk is fairly straight, and the trees will develop a large, rounded canopy that can reach 60 feet if there is sufficient room for them to spread out. If red oak trees are growing close together, the trunk will be somewhat taller with branching occurring at higher levels. They have a tap root system that allows them to search deep in the soil for water. Red oak also has lateral roots that can cause heaving of nearby walk ways.

The leaves of red oak are green during the growing and can turn shades of dark red, yellow and tan during the late autumn. Leaves are generally 8 inches long with a green to blue-green color on the upper surface and a lighter shade of green on the lower surface. The trees grow best in full sun, planted in well drained soil that is slightly acidic.

Red oak is a good choice for a shade tree. It looks appropriate in residential landscapes, parks, and large green areas such as golf courses and campus locations. It may be an appropriate choice for a street tree if there is adequate room for crown growth. Red oak stands up well to urban pollution such as air pollution, poor drainage, and compacted soil, making this tree an option for planting in parking lots as well as along highways. The quantity of acorn litter may be problematic in some locations.

Red oak is a commercially valuable source of lumber. Oak is a very hard, dense wood with coarse graining. The heavy red oak can be machined with precision and is used to make veneers, furniture, interior cabinets, panels, flooring. Red oak is also valued for fence posts and caskets.

In the wild, red oak leaves are eaten by deer, elk, rabbits, moose, and gophers. The acorns are a food source for small animals such as mice, chipmunk, fox, and squirrels. Larger animals that consume red oak acorns include deer, black bear ,and hogs. Birds are also partial to the acorns. The varieties known to eat red oak acorns include bobwhite, woodpecker, jay, tufted titmouse, grackle, nuthatch, quail, grouse, turkey, pheasant, crow, flicker, and thrasher. Water birds who eat the acorns include wood duck, hooded merganser, mallard, and black duck.

Red oaks are a popular nesting site for birds and squirrels who also use the leaves and twigs as nest building material. Early people used the acorns for food after leaching the nuts with ash to remove the bitterness.

Red oak is a monoecious tree having both the staminate and pistillate catkins on the same tree. The acorns can appear both singly and in clusters. The acorns can be up to 1 inch long and are usually round. The acorn cap is thought to look like a beret. It takes two years for an acorn to mature.

Red oak trees can be propagated by transplanting, cuttings, and planting acorns. Even through the direct seeding of acorns in the least expensive method for increasing tree yields, the success rate is dependent on the number of animals in the locale who browse on them. Red oak trees do not bear fruit until they are at least 25 years old. The nut production can be minimal until the trees reach full maturity at 50 years of age. The productive capacity of the nut crop varies on a 2 to 5 year cycle and may also be affected by local weather conditions.

Red oak has predators. The trees are susceptible to oak wilt, oak decline, gypsy moth infestations, and windthrow. Red oak is also negatively impacted by high levels of ozone.

Sources
Quercus rubra, US Forest Service, http://www.fs.fed.us/database/feis/plants/tree/querub/all.html
Quercus rubra, University of Connecticut, http://www.hort.uconn.edu/plants/q/querub/querub1.html
Quercus rubra, Virginia Tech, http://www.cnr.vt.edu/DENDRO/DENDROLOGY/syllabus/factsheet.cfm?ID=38
Quercus rubra, University of Florida, http://hort.ufl.edu/trees/QUERUBA.pdf