Acacias, which belong to the legume family of plants and comprise some 1,300 species, are found in the subtropical regions of South America, Asia, Africa and Australia. They should not be confused with false acacias, which belong to the Robinia genus. Their yellow buds blossom between April and May and shape the landscape of the savannahs, deserts and semideserts. Reaching up to 15 metres in height, acacias can live for up to 200 years. Their striking brown, cracked bark is rich in tanning agents. Their survival is ensured by their symbiotic relationship with nitrogen bacteria, which find an ideal habitat on the roots, where they are supplied with carbohydrates. In return, the bacteria provide essential nutrients for the tree.
Besides their distinctive thorns to protect them from enemies, numerous varieties also have additional chemical defence. When hostile animals begin to eat them, acacia emit a warning to other acacia in the form of a gaseous, colourless, combustible, sweet-smelling organic compound. The resulting production of toxic tanning agents, or “tannins”, gives the acacia verticillata complete protection as the attackers poison themselves when they eat the leaves. The forefather of Monkey 47, Montgomery Collins, probably knew nothing of this brutal process as he liked to spend cold winter days enjoying a sauna infusion with acacia leaves together with his bee-keeping neighbour.