Honey-locust

Leaves

Form

• Deciduous, alternate
• Singly or doubly pinnately compound
• Singly compound preformed in buds, bearing 14–30 leaflets (no terminal leaflet)
• Doubly compound neoformed during the growing season, bearing 4–7 pairs of branches each resembling a singly compound leaf
• Leaflets have a rounded tip, often with a small point

Length

• Leaf and central stalk 25–40 mm

Width

• Leaflets widest near the base

Colour

• Cultivars with yellow leaves common

Autumn colour

• Yellow

Margin

• Sometimes minutely toothed

Buds

Form

• No terminal bud
• Twig ends in a withered stub
• Lateral buds small
• In vertical rows, mostly hidden beneath the bark
• Leaf scars U-shaped with 3 vein scars

Twigs

Form

• Long shoots zigzag
• Short shoots scarcely project beyond the bark
• Bearing leaves and flowers
• Thorns smooth, sharp
• 3-branched
• Occurring on the trunk and stems
• Cultivars used in landscaping thornless

Colour

• Long shoots brownish
• Thorns reddish

Flowers

Form

• Regular, small
• Pollen flowers in long, many-flowered clusters (racemes)
• Seed flowers in few-flowered clusters
• Insect-pollinated

Length

• Pollen flower clusters 5–7 cm
• Seed flower clusters 7–9 cm

Width

• About 5 mm

Colour

• Greenish-white

Structure

• Polygamo-dioecious

Floral timing

• In spring, with the leaves

Fruits

Form

• Flat, curved, twisted
• Husk leathery
• Fall in winter without opening

Length

• 15–40 cm

Colour

• Brownish

Structure

• Legume

Seeds

• Bean-like
• Seed coat hard, impermeable

Seedlings

• Cotyledons fleshy
• Released from the seed coat during germination

Colour

• Turn green during germination

Bark

Form

• Smooth, with horizontal lenticels
• With age becoming deeply furrowed with scaly ridges

Colour

• Brownish

Wood

Texture

• Heavy, hard, strong
• Decay-resistant

Colour

• Reddish-brown

Morphology

• Ring-porous

Figure

• Rays conspicuous

Size

Height

• To 30 m

Diameter

• To 90 cm

Maximum age

• 120 years

Tree form

Forest-grown

Trunk

• Typically short
• Often bearing long branched thorns

Crown

• Broad, open, flat-topped

Root system

• Deep, wide-spreading
• One of the few tree species that has root hairs

Habitat

Site

• Moist, rich bottomlands
• Tolerates droughty and alkaline soils

Light tolerance

• Intolerant of shade

Associated species

• As scattered individuals mixed with other broadleaf trees

Range

Rare in Canada; southwestern Ontario
Planted beyond its range
Common as urban tree