Honeylocust

Gleditsia triacanthos

by Martin (Mort) Schmidt for Simply Living

In the wild, Honeylocust is one of the most recognizable trees because of its long branched thorns. In fact, the Latin species name, triacanthos, means “three thorns”. Honeylocust is very popular for landscaping, but domesticated varieties usually lack thorns and seed pods, so it’s useful to know them by other traits. 

Honeylocust, like its relatives, Black Locust (Robinia pseudoacacia) and Kentucky Coffeetree (Gymnocladus dioicus) have alternate, pinnately-compound leaves. Leaves and branches on alternately-arranged trees are not directly across from each other. On pinnately-compound compound leaves, the leaflets are attached at various points along the petiole, or stem. On palmately-compound leaves, the leaflets are attached to the stem at a single point. But Honeylocusts and Kentucky Coffeetrees do one better – they’re often doubly pinnate (bipinnately compound), and have leaflets attached to stems, which are attached to still larger stems. 

Because they are doubly compound, the leaves on a Honeylocust are very large, but the individual oval leaflets are small. So small that they typically don’t need to be raked, which makes Honeylocust popular for landscaping, together with fast growth and a tolerance for urban conditions. On the downside, Honeylocusts have huge, branched thorns and they drop large, messy seed pods. Therefore, the Honeylocusts used in landscaping are usually cultivars that lack thorns and seed pods. The only other Ohio natives with thorns exceeding one inch in length are the Hawthorns, but their thorns are rarely longer than 1.5 inches, are relatively slender, and don’t form branched clusters. Also, in summer, Hawthorns have simple leaves more than one inch long, far larger than the leaflets on Honeylocust. 

The most conspicuous feature of a domesticated Honeylocust is the doubly-compound leaves with tiny leaflets. In winter, Honeylocust can be recognized by bark that lifts up along the edges. At first glance, Honeylocust bark resembles that of Shagbark Hickory, but Shagbark strips come loose at the bottom, Honeylocust at the edges. The difference is subtle but distinct when you get used to it. The best way to learn Honeylocust bark is to observe it in the woods where the thorns make it is easily recognizable. 

Honeylocust typically reaches a height of 80 feet and a trunk diameter of 2.5 feet. The Ohio Champion, located in Erie County, has a height of 71 feet, a trunk diameter of 6.6 feet, and a crown width of 86 feet. https://ohiodnr.gov/discover-and-learn/safety-conservation/about-ODNR/forestry/champion-trees  Notice that champion rankings are based on a combination of tree height, trunk girth, and crown width, so the champions are often not especially tall. 

The name “Honeylocust” comes from the sweet paste inside the seed pods. Before sweets were widely available, people broke open the pods and ate the paste in between the hard beans. Many of you have tasted tamarind, which comes from the pods of a Honeylocust relative, and is widely used in Asian and Central American food. Honeylocust is also related to carob, whose sweet pods are used as a chocolate substitute. Many sources suggest that the locusts eaten by the Bible’s John the Baptist were carob pods, not insects. 

The wicked thorns on Honeylocust might have evolved to protect it from hungry animals. Honeylocust flowers are inconspicuous, visually, but have a strong, sweet smell in late spring. 

Honeylocust thrives in moist bottom lands, but lives on dryer soils as well, especially in areas with limestone soils. It’s also often associated with abandoned farms and fields. Honeylocust’s native range could be described as the states adjacent to the Mississippi and Ohio Rivers, plus a bit of the adjacent states. 

Honeylocust lumber has a Janka hardness of 1,580 lbf and a density of 0.75 g/cc, compared to the median of my list of 68 Ohio trees of 1,010 lbf and a 0.61 g/cc, according to the Wood Database https://www.wood-database.com/ . Harder than most red oaks and softer than most white oaks and hickories, Honeylocust is well-suited for use in furniture, but its tendency to grow in scattered groups makes it less desirable commercially. Honeylocust has better than average rot resistance and was widely used for fence posts, railroad ties, and other outdoor applications. Like most dense woods, Honeylocust burns very hot and makes excellent firewood. 

According to the Native American Ethnobotany Database, an infusion of Honeylocust bark was used by the Delaware and Cherokee to treat respiratory ailments. http://naeb.brit.org/  Donald Culross Peattie’s A Natural History of Trees of Eastern and Central America reports that the Cherokee also made bows of Honeylocust. Peattie, and Diana Wells’ Lives of the Trees, an Uncommon History, discuss the use of Honeylocust thorns as pins to hold closed the uniforms of Confederate soldiers during the Civil War. 

When you learn to recognize Honeylocust without its thorns, you’ll be surprised how popular it is, and perhaps you’ll come to admire it yourself.