A true seafarer, Caesalpinia bonduc (also known variously Grey Nicker, Gray Nickarbean, Grey Nickernut, Sea Pearl and Fever Nut) is widely distributed along tropical shores worldwide. It is a very widely travelled plant because the seeds are buoyant and can drift immense distances following sea currents. Seeds have been found washed up in Europe, Great Britain, Ireland and Scandinavia, and there are even records of them having been found in Iceland and the Faroe Islands (see link).
It is almost exclusively found near the sea and is instantly recognized by the straggly shrubby habit, two times pinnate leaves and ferocious armature throughout the whole plant, in particular the seed pods. I always approach this plant with great respect and care. The highly attractive yellow five-petalled flowers resemble Cassias somewhat and are borne in racemes.
A partially open seed pod exposing the famous grey ‘nickers’
The seeds of the Grey Nicker are known as nickernuts in the Caribbean, and are incorporated in certain games such as oware. The nickernut is hard and marble-like and has been used as marbles in India. ‘Nicker’ is in fact an old English term, probably derived from the Dutch word “knikker”, meaning clay marble. In Far North Queensland, I have also seen it strung together in aboriginal seed necklaces.
In Wild Medicine in Australia, the Cribbs write that Grey Nicker seeds have a long reputation of being medicinal and has been used in India as a cure for fevers and as a tonic. The oil pressed from the seeds have also been used as a cosmetic to remove freckles, as also to stop discharge from the ears.
Conspicuous leaf-like stipules. A related species in similar habitats, C. crista, has much smaller stipules.
Leaf Whispering in the Tropics 