WSU Clark County Extension
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Red Oak

Scientific name: Quercus rubra
Taxonomy
Family:Fagaceae
Type:Deciduous tree
Native:NO
Plant Requirements
Zone:4 to 8
Sun:Full sun
Plant Characteristics
Height:75 ft
Width:75 ft
Bloom:Spring flowers
Bloom Time:April
Bloom Color:Green
Additional Characteristics
Trees


Fruit

Leaves


Bark
Wildlife value

Poisonous
Description Northern Red Oak is an excellent choice for homeowners who want a quality shade tree as quickly as possible. These stately trees are often planted on golf courses, parks and campuses. Their mature size makes them inappropriate for the smaller urban lot.

  Morphology:
A Red Oak is a deciduous tree which can grow to 60’-75’ in height with nearly an equal spread thus forming a rounded and ascending tree. With maturity the branches become massive. Leaves are arranged in an alternate fashion. They are simple, have 7-11 lobes and have wedge shaped or sometimes rounded bases. Unlike Pin or Scarlet Oak the sinuses on Red Oak only extend one-third to one-half of the way to the midvein.

During the summer the leaves are dull green in color. As the days shorten in the fall a range of colors occurs from yellow-brown to russet-red to bright red.


Flowering commences in April. Red Oaks have male and female flowers on the same tree. The male flowers consist of slender pendulous catkins that spread pollen which is carried by the wind. Female flowers consist of short spikes, not all that notable. Of course the female flower morphs to the acorn. On Red Oaks the acorns are three-quarters inch to one inch long and nearly round. Their cap only covers a fourth of the acorn, resembling a person’s beret hat.

The trunk of Red Oak is straight and long and free from knots if the trees are grown close together in forest. The lumber from this species is used in home construction for flooring, and cabinetry.

  Adaptation:
This tree does best in sandy loam soils which are well drained and acidic. It seems to thrive in the urban areas where air pollution can be a problem.

  Pests:
Oak wilt can be a problem for trees grown in the Midwest. It is typically not problem on the West Coast.
For assistance, contact Dr. Charles Brun (brunc@wsu.edu), (360) 397-6060 5701
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