Osage Orange — The Osage orange (sometimes hyphenated) or Osage apple or simply Osage (Maclura pomifera) is an ornamental plant in the mulberry family Moraceae. It is also locally known as mock orange, “wild orange”, hedge-apple, horse-apple, hedge ball, bois d’arc, bodark (mainly in Oklahoma and Texas), bodart (in northwest Louisiana) and bow wood. “Osage” derives from the Native American people inhabiting the valley of the river of the same name in Missouri. Slang terms for its inedible fruit include monkey brain, monkey ball, monkey orange, and brain fruit, due to its brain-like appearance.
The species is dioeceous, with male and female flowers on different plants. It is a small deciduous tree or large shrub, typically growing to 8-15 m tall. The fruit, a multiple fruit, is roughly spherical, but bumpy, and 7-15 cm in diameter, and it is filled with a sticky white latex sap. In fall, its color turns a bright yellow-green and it has a faint odor similar to that of oranges.
Maclura is closely related to the genus Cudrania, and hybrids between the two genera have been produced. In fact, some botanists recognize a more broadly defined Maclura that includes species previously included in Cudrania and other genera of Moraceae.
The trees range from forty to sixty feet high with short trunk and handsome round-topped head. Juice milky and acrid. Roots thick, fleshy, covered with bright orange colored bark.
The leaves are arranged alternately on a slender growing shoot three or four feet long, varying from dark to pale tender green. In form they are very simple, a long oval terminating in a slender point. In the axil of every growing leaf is found a growing spine which when mature is about an inch long, and rather formidable. The pistillate and staminate flowers are on different trees; both are inconspicuous; but the fruit is very much in evidence. This in size and general appearance resembles a large, yellow green orange, only its surface is roughened and tuberculated. It is, in fact, a compound fruit such as the botanists call a syncarp, where the carpels, that is, the ovaries have grown together and that the great orange-like ball is not one fruit but many. It is heavily charged with milky juice which oozes out at the slightest wounding of the surface. Although the flowering is diœcious, the pistillate tree even when isolated will bear large oranges, perfect to the sight but lacking the seeds.