Plant Profile: Osage Orange

Festive gourds appeared in grocery stores weeks ago, but the trees in the park catch up in their own time and decorate the grass with their own bulbous ornaments. Fall means the pop and splat of acorns, walnuts, and persimmons hitting the ground, and among them you might come across a cluster of those bright green, softball-sized brain-balls: the Osage oranges.

The Osage orange tree, or Maclura pomifera, is called “Osage” after the Native American tribe that prized its exceptionally strong and flexible wood for bow making. As for the “orange,” it isn’t named after its fruit–though you’d be forgiven for guessing so; its fruit is similar in shape and size to a navel orange. But the name actually comes from the orange-colored undertones of its bark.

The orange bark of the Osage orange tree. Photo by Robin Powell.

Osage Orange Trees at the Garden

The Osage orange is native to river valleys and rich bottomlands in Arkansas, Oklahoma, and Texas, but it has been widely planted in a variety of environments throughout the United States and has naturalized in many areas. It is believed, based on correspondence between Meriwether Lewis and President Thomas Jefferson, that Pierre Chouteau was the first to introduce the tree to St. Louis in the 1790s.

Today, they remain a relatively common sight around the city, and the Garden has a few of its own. Shaw planted Osage orange trees in the 1860s to line the carriage trail leading to his country home, Tower Grove House. Some of those trees or their offspring still stand near the Climatron® conservatory and within the Doris I. Schnuck Children’s Garden. Netting has been installed in the Children’s Garden to prevent the large fruits from falling on children at play while still preserving these historic trees. Although much of the original route is gone, with imagination you can trace the trail followed by Shaw and his guests.

More about the Osage orange trees in the Children’s Garden. Shot and edited by Cassidy Moody.

A History of the Osage Orange

Maclura pomifera are exceptionally resilient. They’re resistant to rot, they aren’t susceptible to any serious threat from insects or disease, and their wood is both very strong and exceptionally pliable. All these unique traits have meant that these trees have been put to a number of practical uses throughout the years. As noted earlier, the Osage people took advantage of the sturdy, flexible wood to fashion bows. This practice was so common that the French named the tree after it. You will sometimes hear “bodark” as an alternative common name for these trees–“bodark” is a colloquialism derived from bois d’arc, the name given to the trees by the French. It translates to “bow wood.”

Osage orange trees have also been popularly used as fences or borders, contributing to another common name of theirs: the “hedge apple.” The rot, insect, and disease-resistant properties of the wood make it a great choice for building fences, but the trees can be planted close together and used as living hedges too. Before the advent of barbed wire, this was once quite popular–their thorny branches were an added bonus for deterring trespassers or animals from passing through. They were so efficient that they were once described by an Illinois College biology professor as “horse high, bull strong, and pig tight.” By the 1850s, Osage orange hedges were being used to fence entire farms.

Osage orange trees were once planted at the Garden as a hedge row.

The trees’ distinct green fruit is also rumored to be useful. It is often heralded as a natural insect repellent and is sometimes placed in or around the home to keep away spiders. Studies have shown that a highly concentrated extract from the fruit is effective for repelling insects; however, a regular fruit does not contain a comparable concentration and thus would be ineffective in keeping away spiders.

A young visitor holds a Maclura pomifera fruit. Photo by Sundos Schneider.

Humans aren’t the only ones who have made use of the tree. It is thought that the fruit was once a food source for some animals. This is a mutually beneficial relationship for both animal and plant–an animal eats the fruit, wanders onward as it digests the flesh, and then passes the seeds, thus depositing them in a pile of natural fertilizer far away from the tree that bore the fruit. This way, any potential seedlings don’t have to compete with the parent tree. While squirrels do occasionally move the fruits short distances when they harvest the seeds, recent research suggests they are not typically dispersing the seeds. So now Osage oranges usually just lie there until they rot or are kicked around by visitors to a park. This has led some to believe that the fruits’ original consumers are now extinct–it is likely that the fruit was once eaten by megafauna like wooly mammoths or ground sloths. Even without their animal counterparts to disperse the fruit, the Osage orange trees endure, now a living relic of ancient times.

An illustration of Osage orange leaves and fruit.

Making Use of the Osage Orange

Osage orange trees have lost their relevance as an animal food source, and we don’t recommend that you eat them either–they can cause dermatitis in some people. But Osage orange trees can still be useful to us today in other ways. They are still an effective natural alternative to a barbed wire fence, and their fruit is often used in decorative fall arrangements. They can also be a great choice of tree for property where other plants might struggle, because they don’t mind poor soil as much as most other woody plants.

Osage orange fruits featured in a seasonal display at the Garden. Photo by Tom Incrocci.

If you’re planting them and want to avoid the extra yard waste created by the fruits, you’re in luck–Osage orange trees are dioecious, meaning that its male and female flowers are present in separate individuals. This means that only the female trees bear fruit, so a male can be planted in its stead if you wish.

But there’s something to be said for those bizarre green spheres. Their bright, bumpy  strangeness has the power to speak to the child in all of us. The next time you come across a cluster of them, kick them, throw them, play a game of catch. After all, with their main distributors extinct, they could use a little extra help getting around.

Tree Week is October 27-November 3. Plan your Tree Week and pay a visit to the Missouri Botanical Garden to see the best and brightest of our trees during peak fall foliage.

Kristina Schall DeYong––Digital Media Specialist

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