Honey Locust

Honeylocust (Gleditsia spp.)

Summary Data
Species Size and Bloom Zones
Common Honeylocust (Gleditsia triacanthos) Mature height is 20 to 35’ with a spread the same as the height Zones 4 through 9
  Blooms yellow green in June  
 


Honeylocust trees are native to the United States. It is also known as the Sweet Locust, Thorn Tree, Three thorned Acacia, or Honey Shucks. All of the native species have very serious thorns on their roots, trunk and branches, earning them the dubious distinction of being the most spiny tree in our north temperate zone. We are talking about thorns that can penetrate a farm tractor tire. All the females of the species produce fruit in the form of long pods of seeds, with the pods being 10 to 15 inches long depending on the species. These pods happen to be good as cattle fodder, but in the home landscape they only make a mess.

While most of the several types of Honeylocusts are not very valuable as ornamental plants, there is one exception. The Common Honeylocust (Gleditsia triacanthos) is truly an asset in the yard or park. Fortunately, there are a number of thornless versions of this tree that have no seed pods. A thornless Honeylocust is the only Honeylocust to have in your yard. If you wish, you can get a thornless Honeylocust that does have seedpods, we include both kinds in the list below. This tree is easy to take care of, is resistant to most insects and diseases, has lovely foliage, and flourishes in a wide range of soil types.

One caution to consider is that the Honeylocust has become so popular in some communities in the East and Midwest that they are becoming more vulnerable to insect and disease problems because so many are concentrated in single area. If there are lots of Honeylocusts in your neighborhood, you need to consider that potential problem.

Common Honeylocusts are fast growers. Typically they grow 2 or 2 1/2 feet a year during their first 20 years, reaching maturity at 100 to 125 years. They have an irregular, globular shape and are about as wide as they are tall. Honeylocusts can grow to 35 or 40 feet at maturity, but in a residential landscape they are typically about 20 feet tall. They spread as wide as they are tall, their horizontally growing branches giving them a tiered and flat-topped profile.

They are deciduous, losing their leaves in the fall. Honeylocust leaves are arranged opposite each other on the branches. They are small and egg-shaped, with prominent veins aligned almost parallel to the leaf edges. They turn scarlet red in the fall. Foliage emerges in the spring, usually late May, as many, many elongated, oval leaflets ranged along 8 inch stems. There may be as many as 20 to 30 leaflets on a stem, some trees having double leaves. Because the foliage is so lacy and light, Honeylocusts do not give much shade. New leaves are light green, turning yellow green during the summer. By autumn they are a pale yellow.

Male and female Honeylocust flowers both bloom in June. They emerge in separate clusters on the same tree. Clusters of male ones, called catkins, are the most obvious. They hang about 2 inches or more long and are yellow-green in color. These give way in late July to bean-like, flat pods that hang 12 inches or more from the tree. These purplish-brown pods persist until mid-January when they finally drop.

The wood of Honeylocust is strong, hard and durable. It is resistant to shock and has attractive grain with a reddish-brown color. It is used for fence posts, pallets, crating, general construction, and railroad ties. In some areas it has been valued for making guitars.
 

Honeylocust Choices

Thornless Honeylocust trees can be produced by budding with scionwood taken from the thornless upper branches of selected cultivars. However, seedlings from such trees are thorny. We ve divided the following suggestions into those thornless varieties with no seed pods and those with seed pods.

Thornless With Seed Pods
Inermis (Gleditsia triacanthos) is a spreading, rounded tree that can grow to be 100 feet tall with a spread of up to 70 feet. The flowers are inconspicuous but the long, pea-like pods develop in the late summer and persist into late fall sometimes still dangling from the branches into early winter. The fall color is a warm golden yellow. Bujotii is a weeping form with pendulous branches. Elegantissima is a compact form, thornless and bushy. Maxwell has an irregular form and is very cold hardy;

Thornless With No Seed Pods
Cottage Green is semi upright and seedless. Halka is a very strong, vigorous tree. It occasionally produces fruit. Imperial has a symmetrical and compact, broad crown. Majestic is upright. Moraine is one of the earliest cultivars considered the standard. The deep green foliage turns to yellow in the fall. This tree is a favorite of Municipal Arborists. Shademaster is an old reliable. It has good form and virtually no pods. It has ascending branches. It can begin developing pods after 15 years old. Skyline is an erect, pyramidal tree that has good fall color. Sunburst is a smaller and more compact tree than the species. This tree is fast growing and will reach 30 to 40 feet with a spread of 25 to 30 feet. The leaves emerge in the spring bright yellow and then mature into a light green by summer.