Red oak

Leaves

Form

• Base broadly wedge-shaped
• 7–9 lobes
• Each lobe tapered from base to tip
• Separated by rounded notches
• Lower surface has tufts of hairs in vein axils

Length

• 10–20 cm
• Central lobe about as long as the width of the leaf between opposite notches

Colour

• Upper surface dull yellowish-green
• Lower surface paler

Margin

• Several bristle-tipped teeth on the larger lobes
• Leaves on young trees toothed rather than lobed

Petiole

• Stout
• 1–3 mm wide, 2.5–5 cm long

Buds

Form

• Terminal bud ovoid, pointed
• Mostly hairless
• A few hairs at the tip

Length

• 6–8 mm

Colour

• Shiny reddish-brown
• Hairs brownish

Twigs

Form

• Moderately stout

Colour

• Reddish brown

Flowers

Form

• Pollen flowers small
• In many-flowered drooping catkins
• Seed flowers small
• Solitary or in few-flowered clusters (spikes)

Structure

• Monoecious

Floral timing

• With the leaves

Fruits

Form

• Acorns short-stalked
• Cup saucer-shaped enclosing about one-quarter of the nut
• Scales thin, hairless

Length

• Acorns 12–25 mm

Width

• Acorns almost as wide as long
• Cup 15–25 mm

Colour

• Cup reddish-brown

Structure

• 1-seeded nut

Bark

Form

• Smooth when young, becoming grooved
• Wide, shallow furrows
• Ridges flattish, mostly unbroken, continuous

Colour

• Dark grey when young, becoming darker with pale grey ridges
• Inner bark pinkish

Wood

Texture

• Porous
• Not durable in moist sites

Colour

• Pink to reddish-brown

Morphology

• Attractive grain

Size

Height

• To 25 m
• Occasionally over 30 m
• Stunted on dry rocky ridges toward its northern range limit

Diameter

• 30–90 cm
• Occasionally over 120 cm

Maximum age

• 150 years

Tree form

Forest-grown

Trunk

• Straight

Crown

• Symmetrically rounded

Root system

• Deep, spreading
• With a taproot on deep soils

Habitat

Light tolerance

• Intolerant of competition and shade
• Moderately shade-tolerant when young

Associated species

• Other broadleaf trees and eastern white pine