Bertholletia

The Brazil nut (Bertholletia excelsa) is a South American tree in the family Lecythidaceae, and also the name of the tree's commercially harvested edible seeds. The Brazil nut family is in the order Ericales, as are other well-known plants such as blueberries, cranberries, sapote, gutta-percha, tea, phlox and persimmons. The Brazil nut tree is the only species in the monotypic genus Bertholletia. It is native to the Guianas, Venezuela, Brazil, eastern Colombia, eastern Peru, and eastern Bolivia. It occurs as scattered trees in large forests on the banks of the Amazon River, Rio Negro, Tapajós, and the Orinoco. The genus is named after the French chemist Claude Louis Berthollet. The Brazil nut is a large tree, reaching 50 m (160 ft) tall and with a trunk 1 to 2 m (3.3 to 6.6 ft) in diameter, making it among the largest of trees in the Amazon rainforests. It may live for 500 years or more, and according to some authorities often reaches an age of 1,000 years. The stem is straight and commonly without branches for well over half the tree's height, with a large emergent crown of long branches above the surrounding canopy of other trees. The bark is grayish and smooth. The leaves are dry-season deciduous, alternate, simple, entire or crenate, oblong, 20–35 cm (7.9–13.8 in) long and 10–15 cm (3.9–5.9 in) broad. The flowers are small, greenish-white, in panicles 5–10 cm (2.0–3.9 in) long; each flower has a two-parted, deciduous calyx, six unequal cream-colored petals, and numerous stamens united into a broad, hood-shaped mass. In Brazil, it is illegal to cut down a Brazil nut tree. As a result, they can be found outside production areas, in the backyards of homes and near roads and streets. The fruits are very heavy and rigid; when the fruits fall, they pose a serious threat to vehicles and people passing under the tree. Brazil nut fruits sink in fresh water, which can cause clogging of waterways in riparian areas. Brazil nut trees produce fruit almost exclusively in pristine forests, as disturbed forests lack the large-bodied bees of the genera Bombus, Centris, Epicharis, Eulaema, and Xylocopa which are the only ones capable of pollinating the tree's flowers, with different bee genera being the primary pollinators in different areas, and different times of year. Brazil nuts have been harvested from plantations, but production is low and is currently not economically viable. The fruit takes 14 months to mature after pollination of the flowers. The fruit itself is a large capsule 10–15 cm (3.9–5.9 in) in diameter, resembling a coconut endocarp in size and weighing up to 2 kg (4.4 lb). It has a hard, woody shell 8–12 mm (0.31–0.47 in) thick, which contains eight to 24 wedge-shaped seeds 4–5 cm (1.6–2.0 in) long (the 'Brazil nuts') packed like the segments of an orange.