Phenology

• Title

  Phenology

• Authors

  Scott Alan Mori

• Description

  Flowering of Bertholletia excelsa occurs during the dry season and into the wet season. In fact, Brazil nuts grow naturally only in regions with a three-to-five-month dry season (Müller, 1981). In the eastern part of Amazonian Brazil, flowering begins at the end of the rainy season in September and extends to February. Peak flowering occurs in October, November, and December (Moritz, 1984). Toward the end of the rainy season, generally in July, the leaves of Brazil nut trees begin to fall. The new growth flushes from directly below the inflorescences of the previous year, and the new inflorescences are produced at the apex of the current growth flush. Large numbers of flowers are produced daily over a relatively long period. The flowers open between 4:30 a.m. and 5:00 a.m. However, the anthers start to dehisce within the bud several hours before the flowers open. The petals and androecia fall in the afternoon of the day that the flowers open (Mori and Prance, 1990b). Fruit development takes longer in B. excelsa than in any other species of Lecythidaceae. Moritz (1984) states that 15 months are needed for the fruits to develop after they have been set. Consequently, Brazil nut fruits fall mostly in January and February, during the rainy season. Under natural conditions, the seeds take 12 to 18 months to germinate (Müller, 1981).