Osage orange (Maclura pomifera): how to identify the hedge apple tree

Male and female trees

Osage orange is dioecious. Male and female flowers grow on separate trees, both tiny and green in round clusters about an inch across, appearing from May to June after the leaves. Only female trees grow hedge apples. The Forest Service notes that a female with no male nearby can still set fruit, but without seed.

That means a large share of Osage oranges never fruit, and those are usually the ones people struggle to name. A fruitless tree with thorns, milky sap, untoothed glossy leaves and orange bark is a male Osage orange. Nurseries also sell male, largely thornless cultivars; NC State Extension lists 'Park', 'White Shield' and 'Wichita', and the Morton Arboretum describes 'White Shield' as fruitless with few to no thorns. Iowa State adds that no cultivar has been found that is completely thornless.

Where Osage orange grows and why it is everywhere

The native range is small: the Red River drainage of Oklahoma, Texas and Arkansas, plus the Blackland Prairies, Post Oak Savannas and Chisos Mountains of Texas. Yet the Forest Service reports that it was planted as a hedge in all 48 conterminous states and in southeastern Canada.

The reason is fencing. Before barbed wire, prairie farmers planted Osage orange in rows and cut it back to make thorny living fences; the Forest Service says hedges around every quarter-section were common, and credits the hedges with leading directly to the invention of barbed wire. Many old hedgerows still stand along field edges in Kansas, Missouri, Iowa, Illinois and Ohio, which is why the tree so often appears in straight lines along fences rather than in forests. The Missouri Department of Conservation lists fencerows, pastures, woodland edges, thickets and stream valleys as its usual places, and says it was introduced throughout Missouri long ago, possibly by Native Americans.

The Morton Arboretum notes that it suckers freely and is considered invasive in some areas of the United States.

Wood, bows and dye

Osage orange wood is the reason for most of its names. The Missouri Department of Conservation calls it the premier bow wood of North America, and the French name bois d'arc ("bow wood", Americanized as bodark) records that use. The Forest Service rates the heartwood the most decay-resistant of all North American timbers and immune to termites, and reports that about 3 million posts were sold annually in Kansas in the early 1970s.

Iowa State University Extension describes the wood as golden yellow or bright orange when freshly cut, turning brown with exposure, and extremely hard, heavy and durable; a bright yellow dye can be extracted from it. For a firewood pile or an old fence post, that orange color is the quickest confirmation. See identifying trees for firewood for other woods by color and grain.

Hedge apples: myths and cautions

Hedge apples are widely placed in basements to keep spiders away. Iowa State tested the idea: chemicals extracted from the fruit did repel German cockroaches, mosquitoes and houseflies, and sliced fruit worked in small enclosed spaces, but the university found no evidence that whole fruit placed around a house affects pests and does not recommend it. The Missouri Department of Conservation also says the fruit is unlikely to repel spiders or insects indoors.

On safety, stick to what the sources state. The milky sap and fruit juice can irritate the skin (USDA Forest Service, Iowa State, Missouri Department of Conservation). Iowa State notes that the fruit was once suspected of poisoning livestock, that studies in several states were negative, but that a fruit can lodge in a cow's or other ruminant's esophagus and kill it. Most birds and animals find the fruit unpalatable; the Missouri Department of Conservation notes that squirrels tear it open for the seeds. And the thorns are a real hazard when pruning or mowing.

Telling it from look-alikes

The fruit has no real look-alike, but a fruitless tree does. Mulberry is the closest: same family, same milky sap, sometimes the same orange-tinged bark. But mulberry leaves are toothed and often lobed or mitten-shaped, and the twigs never carry thorns; see the mulberry page. Honey locust and black locust are the other thorny trees of fencerows, but both have compound leaves and bean-like pods, and neither has milky sap; the tree with thorns guide sorts them by thorn type.

People also mix up the fruit itself with other green balls in summer, such as young sweetgum and sycamore balls or black walnuts in their husks. The tree with green balls guide covers them by size and texture, and the tree with spiky balls guide handles the prickly ones.

When a photo helps

Tree Identifier names a tree from one photo of the fruit, a leaf, the bark or the whole tree, and a hedge apple on the ground beside a leaf makes an easy picture. Osage orange is not one of the 138 species in the app's Collection, so the result is saved in your History and Wild Discoveries. The app does not show a confidence score or a look-alike list, so check the result against the thorns and sap. Tree Identifier's follow-up chat can answer questions such as how hedgerow Osage orange was managed, and the Tree Map remembers where a fruiting female stands so you can find it again next fall.