The osage orange is one of the most unusual members of the mulberry family (Moraceae). This tree bears orange-sized fruit, a lurid neon green in colour, high up in the tree. In autumn, the ground beneath the tree becomes littered with the fruits, which look like green, deeply wrinkled tennis balls – or, as the horticultural staff call them, “pickled gardeners’ brains”!
Moraceae includes other well-known plants such as fig, breadfruit and jackfruit. Another member of the family, white mulberry (Morus alba), is commercially important because it is the preferred foodplant for caterpillars of the silkworm (Bombyx mori). Each caterpillar eats around 40g of mulberry leaves as it grows, before spinning silk into a cocoon in which to pupate. Each cocoon yields around 1,000 yards of raw silk filaments, weighing 0.2g. These filaments are combined into thread, which is then twisted together into yarn.