Senna reticulata, a pioneer tree from Amazonian várzea floodplains

Abstract

Senna reticulata can be considered one of the most efficient colonizers of open areas in the nutrient-rich Amazonian floodplains. Its main strategies for success are a high tolerance for waterlogging of its roots and stems and extremely high photosynthetic assimilation and rapid growth during the first terrestrial period, when height is important to avoid lethal submergence. The density of the crown is important in outshading competitors. Efficient seed dispersal and a great ability to resprout after a period of unfavorable conditions, after cutting, or after predation add to its effectiveness. These features led local people to consider Senna reticulata a noxious woody weed called matapasto. In the present article I describe the ecological, physiological, and phenological characteristics of Senna reticulata, with its extremely high productivity and unique capacity to colonize open areas.