Blue Ash

Fraxinus quadrangulata

Family: Oleaceae (oh-lee-AY-see-ee) (Info)
Genus: Fraxinus (FRAK-si-nus) (Info)
Species: quadrangulata (kwad-ran-gew-LAY-tuh) (Info)



Foliage Color:

Unknown - Tell us

Bloom Characteristics:

Unknown - Tell us

Water Requirements:

Average Water Needs; Water regularly; do not overwater

Where to Grow:

Unknown - Tell us


over 40 ft. (12 m)


30-40 ft. (9-12 m)

over 40 ft. (12 m)


USDA Zone 4a: to -34.4 C (-30 F)

USDA Zone 4b: to -31.6 C (-25 F)

USDA Zone 5a: to -28.8 C (-20 F)

USDA Zone 5b: to -26.1 C (-15 F)

USDA Zone 6a: to -23.3 C (-10 F)

USDA Zone 6b: to -20.5 C (-5 F)

USDA Zone 7a: to -17.7 C (0 F)

USDA Zone 7b: to -14.9 C (5 F)

Sun Exposure:

Full Sun



Bloom Color:


Bloom Time:

Late Spring/Early Summer



Other details:

Unknown - Tell us

Soil pH requirements:

5.6 to 6.0 (acidic)

6.1 to 6.5 (mildly acidic)

6.6 to 7.5 (neutral)

7.6 to 7.8 (mildly alkaline)

Patent Information:


Propagation Methods:

From seed; direct sow outdoors in fall

Direct sow as soon as the ground can be worked

By grafting

By budding

Seed Collecting:

Allow seedheads to dry on plants; remove and collect seeds

Properly cleaned, seed can be successfully stored


This plant has been said to grow in the following regions:

Wildomar, California

Batavia, Illinois

Lemont, Illinois

Lisle, Illinois

Poplar Grove, Illinois

Clermont, Kentucky

Frankfort, Kentucky

Georgetown, Kentucky

Lexington, Kentucky

Louisville, Kentucky

Nicholasville, Kentucky

Paris, Kentucky

Versailles, Kentucky

Osseo, Minnesota

Cary, North Carolina

Raleigh, North Carolina

show all

Gardeners' Notes:


On Dec 12, 2013, Rickwebb from Downingtown, PA wrote:

A few large nurseries northwest and west of Chicago did grow this species in the 1990's. I planted three in Hinsdale, IL on the hospital grounds about 1995. One died from transplant shock. The other two did well until the hospital put a huge utility unit in that area, taking out everything. It makes a good shade tree. I like its texture better than the abundant Green Ash. There is a wonderful grove of them growing on the the very alkaline dolomitic limestome soil of Glenwood Park on the east bank of the Fox River, off Rt #25, in Batavia, IL , where I took most of my photos. The pH there could be 8.0 to 8.5. Someone in Bolingbrook, Il, reported some wild ones growing there.


On Aug 19, 2013, BruceStationGar from Bruce Station
Canada wrote:

Deb McCullough of Michigan State did a study on this tree under pressure from emerald ash borer (that is killing ash at a rate of 100%) the blue ash, one of our native ash trees is surviving!! We have to plant more of these trees.


On Oct 15, 2006, ViburnumValley from Scott County, KY (Zone 5b) wrote:

Blue ash is one of the longest lived trees for central KY, partnering well with the bur oak and chinkapin oak in the agricultural landscapes around the Bluegrass. This tree ranges far into the upper midwest as well, especially on limestone-based soils.

I agree with the other posts here, and also encourage more planting of this tough tree. It is easy to sprout from seed, and more native plant growers are starting to offer small plants.


On Nov 12, 2004, melody from Benton, KY (Zone 7a) wrote:

Mainly a Midwestern tree seen in upland, dryish conditions.

Trunk bark whitish and somewhat scaly.Compound leaves 8" to 12" with 7 to 11 leaflets. A tall tree that flowers April/May, fruits are not plump and the wing extends to the seed base.

A nice hardwood tree with many uses, among which is the blue dye that the inner bark produces.


On Sep 7, 2003, Glowclubbr from Silver Spring, MD wrote:

Endangered in wild in Southern Ontario due to near complete destruction of native forest. It grows very well in cultivation, tolorates limestone soils VERY WELL, and is drought-tolerant.

It can grow fast, usually grows to 60 feet, but can exceed 120 feet. It is an excellent, hardy, extreme heat-tolerant, and sturdy street tree. My own turned a very attractive butter yellow in fall, superior to nearby Green Ashes. I do not understand why there are so many Green Ash hybrids, while the Blue Ash is superior in every way. It also has better foliage. Interestingly, the Blue Ash is the only Ash with square twigs just like the Euonymus alatus.