Quercus rubra (Red Oak)

Michael's Opinion

A native plant of exceptional character, the Red Oak turns a bright red in autumn and often retains its leaves into the winter months. It is an upland species found in climax forests along scree and sandy ridges and lean soil areas. It is often used in park and commercial landscape developments. Leaves, in cultivated specimens often remain clean throughout the season and it seems tolerant of minor urban conditions. Its broadly pyramidal form in late autumn colour can be a striking accent in large park-like landscapes.

Botanical Information

FamilyFagaceae
GenusQuercus
Speciesrubra
CategoryWoody
TypeTree (deciduous)
OriginEastern North America.
Pronunciation

Details

USDA Hardiness Zone4 - 8
USDA Hardiness Ref.
Canadian Hardiness Zone2a - 8a
Canada Hardiness Ref.
RHS Hardiness ZoneH7 - H4
RHS Hardiness Ref.
Temperature (°C)(-32) - (-7)
Temperature (°F)(-25) - 20
Height25-30 m
Spread10 m
GrowthFast
Flowering PeriodMay

Description and Growing Information

ID CharacteristicDeeply lobed leaves turning an intense red in autumn and persisting into the winter and remaining often unblemished.
ShapeSomewhat rounded crown, regular in appearance.
LandscapeSpecimen, street or lawn tree.
PropagationCommonly through seed, although the seed is reclacitrant (will not store). Seeds should be placed in a fridge for 60 days at 5°C before being sown.
CultivationWell drained lighter soils that are slightly acidic, although I have rarely seen it experience problems with iron deficiency.
PestsSeldom a problem in cultivation.
Notable SpecimensWeldon Library, University of Western Ontario, London, Ontario, Canada. Westonbirt, The National Arboretum, Tetbury, Gloucestershire, England. Stourhead Gardens, Wiltshire, United Kingdom.
HabitatFound at altitudes of 0-1,800 m.
Bark/Stem DescriptionSmooth when young and dull grey in colour, developing slight ridges and furrows as it matures.
Flower/Leaf Bud DescriptionOval shaped buds to about 7 mm, dark brown to reddish brown in colour. Slightly tomentosa.
Leaf DescriptionSimple leaves, alternate in arrangement to about 22 cm long. Lustrous dark green and paler on the underside, turning deep red and then brown in the autumn. Persisting into the winter months. Often up to eleven lobes but frequently less, with a sharp apex.
Flower DescriptionCatkins, 5-8 cm in length.
Fruit DescriptionA squat acorn (3 cm) often solitary or in pairs and takes two years to reach maturity.
Colour DescriptionShiny green and turning red in the autumn.
Texture DescriptionMedium.

Photographs