Osage orange (Maclura pomifera) derived its common name from the Osage Indians in Oklahoma and Texas and the orange-smelling fruits. The Latin name comes from William Maclura, an American geologist (1763-1840), and from the grapefruit-size, heavily wrinkled, spherical pomes or apples (inedible for humans) it produces. Many a farm child has used these fruits for baseballs!
The tree was native to Arkansas, Oklahoma, and Texas, but in the last century the tree has “escaped” and is found throughout the U.S. It is most commonly known as Osage orange, but other names include hedge, hedge-apple, yellow-wood, bowwood, Osage apple, and bodark (from the French bois d’arc, meaning bow wood).
The sharp thorns of this tree led to its planting for hedgerows that performed as excellent fences for cattle. It also was widely planted to stabilize erosion during the Dust Bowl.
The extremely high strength of this wood led to its use for archery bows and for wheel rims and axle hubs for wagons. It is probably the most naturally decay resistant species in North America.
Yet it seems terrible to use such a beautiful wood for non-appearance items. The beautiful coloring has led to limited use for turnings and novelties, such as wooden pens, as well as for accent wood in musical instruments, substituting for ebony at times.
The root wood and bark, and to a lesser extent the wood itself, have a great amount of yellow coloring that can be extracted in hot water and used as dye. Native Americans used this coloring. In World War I, the dye was used for khaki coloring.
Processing suggestions and characteristics
Density: Osage orange averages about 50 pounds per cubic foot at 7 percent MC. This is 30 percent heavier than oak! KD lumber, 1 inch thickness, weighs over 4 pounds per board foot.
Drying: This wood must be dried slowly to avoid checking. However, it does dry without much warp. End coating is essential. Treat 4/4 Osage orange like 8/4 red oak. Shed drying of green lumber before kiln drying is probably best. Shrinkage in drying is about 5 percent; quite low, especially considering its density.
Gluing and machining: Gluing is easy with most adhesives. Machining is difficult due to the high density, but with sharp tools and patience, machining and the finish obtained is excellent with a high luster.
Stability: Osage orange is subject to very small size changes when the MC changes — about 1 percent size change for each 7 percent MC change across the grain parallel to the rings (tangentially), and about 1 percent size change for each 9 percent MC change across the rings (radially).
Strength: The bending strength (MOR) is over 20,000 psi. Hardness is around 2,000 pounds. Stiffness (MOE) averages 1.8 million psi.
Color and grain: The wood is ring porous, like oak and ash, so it has a strong grain appearance. The heartwood color is golden yellow, but this color does age slowly toward a russet brown. The appearance is exceptionally lustrous.
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