Oak, red (Quercus rubra)
Red oak is a broadleaf deciduous tree native to North America.
Common name: red oak
Scientific name: Quercus rubra
UK provenance: non-native
Interesting fact: it takes 20 years before the trees are ready to flower, and a further 20 before they produce a good crop of acorns.
What does red oak look like?
Overview: red oak can grow to 25m and develop a rounded crown. The bark is smooth and silver-grey when young, and develops warts or ridges with age. Twigs are straight, slender and dark brown.
Leaves: similar to those of English and sessile oaks, but more pointed. They have a few lobes each with several teeth and pointed, whiskery tips. Dark green in colour, they have a paler, matted appearance on the underside, and fade to a bright red before falling in autumn.
Flowers: slender male catkins hang in clusters and the tiny, inconspicuous female flowers are found singly or in clusters.
Fruits: after pollination by wind, female flowers develop into a fruit enclosed by a rounded cup, known as an acorn, which takes two years to ripen.
Look out for: the large leaves have long lobes each with 1-3 teeth.
Could be confused with: unlikely to be confused with anything when leaves are present. The acorn cups are shallow and knobbly.
Identified in winter by: the buds are long and taper to a point. Each bud has more than three scales.
Where to find red oak
It was introduced to the UK and is grown as an ornamental tree in parks and gardens, where it is prized for its incredible autumn colour. Red oak was extensively used as a forest tree in Europe in the nineteenth century and in Britain after 1920. It requires full light and lots of space.
Value to wildlife
Red oak is not as valuable to native wildlife as English and sessile oaks, but its catkins provide pollen for bees and other insects in spring, and its acorns are eaten by birds and small mammals. The rounded crown provides nesting opportunities for birds.
Mythology and symbolism
In North America the red oak is the provincial tree of Prince Edward Island, as well as the state tree of New Jersey.
How we use red oak
Red oak is mainly planted as an ornamental tree in parks and gardens, for its rich autumn colours. The timber may also be used, but it is not as strong as that of English and sessile oaks.
Red oak is less susceptible to pests and pathogens than our native English and sessile oaks, although it may be susceptible to oak processionary moth.