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Black ash (Not recommended)

A young black ash tree.

Due to susceptibility to emerald ash borer (EAB), black ash is not recommended for planting anywhere in this region and usually requires removal and/or replacement.  Black ash is a medium-sized, native tree adaptable to wet sites. Currently, ash trees cannot be sold in Illinois. Check with your state for quarantine restrictions. 

This species is native to the Chicago region according to Swink and Wilhelm's Plants of the Chicago Region, with updates made according to current research.

Botanical name:

Fraxinus nigra

All common names:

black ash

Family (English):


Family (Botanic):


Tree or Plant Type:

  • Tree


  • Deciduous (seasonally loses leaves)

Native Locale:

  • Chicago area,
  • Illinois,
  • North America

Size Range:

  • Large tree (more than 40 feet)

Mature Height:

40-50 feet

Mature Width:

20-35 feet

Light Exposure:

  • Full sun (6 hrs direct light daily)

Hardiness Zones:

  • Zone 2,
  • Zone 3,
  • Zone 4,
  • Zone 5 (Chicago)

Soil Preference:

  • Acid soil,
  • Wet soil


  • Wet sites,
  • Occasional flooding,
  • Alkaline soil,
  • Clay soil

Acid Soils:

  • Tolerant

Alkaline Soils:

  • Tolerant

Salt Spray:

  • Moderately Tolerant

Soil Salt:

  • Moderately Tolerant

Drought Conditions:

  • Intolerant

Poor Drainage:

  • Prefers

Planting Considerations:

  • Highly susceptible to ice damage

Ornamental Interest:

  • Persistent fruit/seeds,
  • Attractive bark

Season of Interest:

  • Early fall

Flower Color & Fragrance:

  • Inconspicuous

Shape or Form:

  • Narrow,
  • Open

Growth Rate:

  • Slow

Transplants Well:

  • Yes


  • Browsers,
  • Game birds,
  • Insect pollinators,
  • Migrant birds,
  • Songbirds

More Information:

Tree & Plant Care

This tree is tolerant of wet sites.  It prefers slightly acidic soil.

Disease, pests, and problems

Susceptibility to the emerald ash borer makes this tree unsuitable for the landscape.

Native geographic location and habitat

C-Value: 10

Commonly found in wet, lowland sites.

Bark color and texture 

The bark is light gray and loosely ridged and furrowed.

Leaf or needle arrangement, size, shape, and texture

Compound leaves are in pairs (opposite), with 7 to 11 leaflets on each leaf.
Leaves are dark green in summer, changing to purplish in fall.

Flower arrangement, shape, and size

Male and female flowers on separate trees (dioecious).  Not ornamentally important.
Flowers appear in spring.

Fruit, cone, nut, and seed descriptions

Fruit formed on female trees only.  They are winged seeds.



Location of Fraxinus nigra (Black ash (Not recommended)) at the Arboretum

We do not seem to have this in our living collection.