Myrianthus arboreus aka Giant Yellow Mulberry

Myrianthus arboreus is an evergreen tree. It belongs to the nettle family, Urticaceae. Its common names include giant yellow mulberry and monkeyfruit. It grows in tropical Africa, from Guinea east to Uganda. Its range extends south to Angola and Tanzania. It lives in forest clearings and damp woods. It also grows where woods have grown back. Other sites include stream banks, lake shores, and flooded ground.

Garden sources give a height of about 49 feet [15 metres]. The tree can spread to 33 feet [10 metres]. Wider accounts give heights of up to 66 feet [20 metres]. The short trunk often splits or branches near the ground. Many branches form a wide crown above stilt roots. These roots can reach about 2 feet [0.6 metres] long. The leaves feel like leather and have pale undersides. Each has seven to nine leaflets, or smaller leaf parts. Each whole leaf can span about 2.3 feet [0.7 metres].

Male and female flowers grow on separate trees. Trees of both sexes must grow near each other. This lets them form fruit and seeds. Trees grown from seed may first fruit after four or five years. The heart-shaped fruit starts hard and green. It turns soft and yellow as it ripens. Each fruit holds five to fifteen seeds in sweet or tart pulp. People eat ripe fruit raw and cook the seeds. They also cook young leaves, often adding them to soup. The seeds hold oil rich in linoleic acid.

This tree suits warm, wet tropical sites. It grows at a moderate rate. Sources give mean yearly site temperatures of 16–26°C. It needs sun, not shade, and prefers damp soil. Sand, loam, and clay can all suit it. Soil should drain well but stay moist or wet. It tolerates slightly acid, neutral, and slightly alkaline soil. PFAF lists USDA zones 10–12. Fresh seed works best to grow new trees. A twelve-hour soak in warm water can help seeds sprout. Trials have also worked with stem cuttings and bud grafting.

People use this tree for food and household goods. They also use it in folk medicine. Farmers may keep it when they clear woods for crops. Its large fallen leaves cover soil and help keep it moist. They form a thick layer of humus as they decay. Wood ash gives lye for making soap. In tests, plant extracts have deterred one termite species. Folk remedies use bark for throat and chest complaints. These uses do not prove that such care is safe or works. The sources report no known hazards. They do not show that the tree is safe for pets.