Milicia regia is a majestic, large-crowned tropical tree native to the moist high forests, river valleys, and savanna woodlands of West Africa. Its specific epithet regia—Latin for 'royal' or 'regal'—reflects its commanding stature in the forest canopy, where straight, cylindrical trunks rise high above the understory to support a wide, rounded dome of dark green foliage.
The species belongs to the mulberry and fig family, Moraceae. First described by the French botanist Auguste Chevalier in 1912 as Chlorophora regia from specimens collected in the Fouta Djallon highlands of Guinea, it was placed into its current accepted genus by Cornelis Christiaan Berg in 1982.
Mature trees develop a tall, straight bole that can reach up to a meter or more in diameter, covered in smooth to finely scaly reddish-brown bark that exudes a white to yellowish latex (milky sap) when cut. The leaves are arranged alternately along the twigs on short petioles and display clear diagnostic features:
Milicia regia is strictly dioecious, meaning male and female flowers grow on separate individual trees that even differ slightly in silhouette—male trees tend to be taller and more slender than female ones. Both sexes bear their tiny, wind-pollinated flowers in axillary catkins (hanging or upright cylindrical flower spikes):
Within five to six weeks after pollination, the female catkin swells into a fleshy, yellowish syncarp—a multiple fruit similar in structure to a long mulberry—packed with tiny seeds.
Dry season to early rains (January to March)
Together with Milicia excelsa, this tree is the source of commercial iroko (known locally as odum in Ghana), one of Africa's most prized hardwoods. The heartwood is yellow-brown to rich golden-brown with darker streaks, naturally resistant to rot, fungi, and termites, making it a staple for heavy construction, boatbuilding, flooring, fine furniture, and traditional wooden mortars.
Although foresters have attempted to establish commercial timber plantations of Milicia regia, monoculture plantings face severe setbacks from the gall-forming jumping plant louse Phytolyma lata, which attacks the tender shoots of young saplings.
Relying on the wind to carry pollen through a dense, humid tropical forest is a major physical challenge, because still air and thick foliage quickly trap drifting grains. Milicia regia overcomes this obstacle through a remarkably coordinated division of labor between male and female trees, starting with their physical architecture.
Male trees grow noticeably taller and narrower than females, lifting their 20-centimeter pendulous catkins into the faster, turbulent air currents above the main canopy. Flowering is also staggered in time and space:
Once fertilization is complete, the tree switches from wind to wildlife: in just five to six weeks, the green spikes transform into fragrant, yellow, mulberry-like syncarps that drop to the forest floor, recruiting fruit-eating bats, birds, and mammals to carry the tiny seeds to sunlit clearings with well-drained soil.
Taxon Synonyms: Maclura regia, Chlorophora regia
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