Scientific: Gleditsia triacanthos f. inermis (inermis means thornless because once you've seen the 'non-imeris' - Wow!! those are thorns!)
Common: honey locust
Family: Fabaceae (Leguminosae)
Origin: Temperate portions of Eastern United States, Pennsylvania to Nebraska and south to Texas and Mississippi.

Pronounciation: Gle-DIT-see-a tri-a-CAN-thos i-NER-mis

Hardiness zones
1-16, 18-24 (Too much Pacific marine influence in 17)
USDA 1 (note the cold tolerance of this tree!)-11

Landscape Use: Honey locust is a deciduous shade tree that casts a dappled shade. It makes a great streetscape or lawn tree in the Phoenix area.

Form & Character: Honey locust is a winter deciduous tree with an upright and arching habit and an inverted vase form. It has a rigid and distinctively roughened trunk as well as lacey and graceful appearance when fully foliated.

Growth Habit: Moderately fast growth, upright and vigorous to 50 to 70 feet in height, open inverted vase like form is ideal for urban landscape sites, dense wooded.

Foliage/texture: Leaves alternate, pinnately or bipinnately compound, 6 to 8 inches long, pubescent rachis, ovate leaflets are only 1 to 2 inches long. Subspecies inermis is thorn less, smooth to somewhat roughened dark bark; medium texture.

Flowers & fruits: Inconspicuous yellow-green, catkin-like flowers during spring followed by long black bean pods to 6 to18 inches long during summer and fall.

Seasonal color: Honey locust has an in consistent yellow fall color in lower elevation desert landscapes.

Temperature: Honey locust grows best in climates with marked seasons. It is heat loving.

Light: Full sun, avoid reflected western sunlight as prone to sunscald in lower desert.

Soil: Very tolerant

Watering: Drought tolerant, but does well in lawns.

Pruning: Elevate canopy base

Propagation: Cutting, grafting

Disease and pests: Honey locust is susceptible to several canker diseases, especially following transplanting and when otherwise under stress. Webworm, spider mites, pod gall midge, and honey locust plant bug can seriously damage the foliage, there are no controls.

Additional comments: This is good tree for mesic and oasis landscapes in arid desert climates because of its wide adaptibility to different growing conditions and landscape situations. Honey locust tolerates a wide range of climate type across the United States (here it is being grown as an urban tree in Cleveland, OH), except for the mild coastal climates of central and southern California (no seasonal distinctions) where it struggles.

Selected Cultivars:

HalkaTM - this is a relatively new cultivar that has not been thoroughly tested for winter hardiness in the upper Midwest but appears promising at the Minnesota Landscape Arboretum. It grows vigorously with a horizontal branching structure and a broad rounded crown. It does produce some pods.

`Imperial' - has a compact rounded crown with a wide branching habit. Has a more formal shape than most cultivars of honey locust. Slightly less hardy than `Skyline'.

`Moraine' - is one of the first selected varieties and first patented plant in United States. It has a rounded crown with vase shaped branching structure. It has an irregular form and often requires staking when young to develop a straight trunk.

`Shademaster' - has a rounded crown with upright, vase shaped branch habit. Has a straight trunk and grows rapidly.

`Skyline' - has a good symmetrical form with a broadly pyramidal crown and spreading to upright branching habit. Has very good yellow fall color. It is probably the most widely planted cultivar. Hardier than most other cultivars.

`Summer Lace' - is a fast growing cultivar with light green new foliage that becomes darker green as it matures.

'Sunburst' - has bright yellow new growth. Has a broad oval crown with a very irregular growth habit. Requires staking when young to develop a straight trunk. Very susceptible to nectria canker.