In Iowa the osage orange (Maclura pomifera) is a medium-sized tree, 50 to 60 feet in height, has been widely planted in hedges. It grows with a short trunk and upwardly arching branches, forming a low, rounded crown.
Hardiness: Zones 4 through 9
Growth Rate: Fast
Mature Shape: Irregular
Height: 30-40 feet
Width: 30-35 feet
Site Requirements: Full sun; adaptable to most soil conditions
Leaves: Alternate, simple, with thorns or spines present
Flowering Dates: April - June
Seed Dispersal Dates: September - October
Seed Bearing Age: 10 years
Seed Bearing Frequency: Yearly
Seed Stratification: Prechill for one month at 34°F to 40°F
The leaves are 3 to 5 inches long and do not have teeth along the margin. They are thick, firm, and dark green in color. The buds are partly hidden in the bark and the terminal bud is absent. The twigs have thorns that are straight and 1/2 inch in length.
The fruit is round, wrinkled, pale green in color and 4 to 5 inches in diameter. It consists of numerous small seeds crowded and grown together to form the characteristic "orange." When crushed, the pulpy fruit gives a bitter, milky juice.
The bark on young twigs is green. On older trunks it is orange-brown and deeply furrowed. The inner bark is bright orange. The bark of the roots is also a bright orange color and furnishes a yellow dye.