History of Brazil Nuts

The Brazil nut is a hard shelled seed from the Brazil nut tree. The Brazil nut tree, also known as the castana tree, is from the Bertholletia excelsa in the family Lecythidaceae that includes approximately 200 species in the Neotropics, spread out from southern Mexico into southern Brazil.  The Brazil nut represents only a single species in of the genus Bertholletia.  Although there is considerable variation in fruit size and shape and number of seeds per fruit, there is no justification for recognizing more than one species of Bertholletia.

It is the only species in the genus Bertholletia and can be found in the Amazon forests of Brazil, Bolivia, Peru, Columbia, the Guianas, and Venezuela. The Brazil nut tree reach heights of about 150 feet, their trunk can be about 8 feet in diameter and can live about 500 years. This tremendous tree only has branches and leaves at the top third of the tree. The branches can span a hundred feet providing a canopy over other rain forest vegetation. The leaves of the Brazil nut tree are long, green and waxy. At the end of the leaf is a yellow orchid. This flower, when pollinated, produces the fruit that contain the Brazil nuts.

Flowering happens during the dry season and continues into the wet season.  Dry season is very imporant for Brazil nuts, they grow naturally only in areas with a 4-month dry season.  In the eastern part of Amazonian Brazil, the flowering starts near the end of the rainy season in September and runs into February.  October, November, and December are when the Peak flowering happends.

Cross-pollination is required for seed set in Neotropical Lecythidaceae.  The Brazil Nut tree depends on bees, and bats to pollinate the flowers and begin the fruit and seed development of Lecythidaceae.

The large shelled fruit, similar to a coconut, takes about 14 months to mature. The fruit is about 4-6 inches in diameter and can weigh up to 4 pounds. The shell of the fruit is about a quarter of an inch thick and inside clustered together are between 12-24 brazil nuts.

Brazil nuts are primarily harvested from wild trees during six month period in the rainy season. The fruits weigh between 0.5 to 2.5 kilograms and contain about 20 seeds. The brazil nut trees are so tall that harvesting the fruits consists of gathering the fruit after they fall. Once the fruit falls, it has to be gathered quickly since they are susseptible to fungal attack, and animals also carry the fruit away.

Recently plantations are being designed and developed in the amazon in order to grow and harvest the Brazil Nuts. Most plantations have plenty of pollinators since they plany Bixa orellana in the general vacinity if the Brazil nut trees to provide pollen as food for pollinators.  There are also large natural forest surrounding these plantations and windrows run through the plantation and are carefully maintainted with natural vegetation.  These windrows are home to many plants that are a food sources for the pollinators of Brazil nut trees.