Senna occidentalis (coffee senna).
Abstract S. occidentalis is an annual to short lived perennial herb to small shrub with a pantropical distribution (PROTA, 2016). It is reported as invasive throughout Oceania, and various countries in Asia and Africa, where is reported as introduced (BioNET-EAFRINET, 2016; PIER, 2016). Within its native range S. occidentalis is listed as invasive for Cuba by Oviedo Prieto et al. (2012). This species is recognised as an invasive herb or a problematic weed that affects crops and plantations all over its range (PIER, 2016). For example, in the Northern Territory, Australia, it is a class B declared weed, i.e. spread to be controlled in all of the Territory (Flanagan, 1998). This weed is a problem in seven states of the USA and is increasing in eight others (Teem et al., 1980). Its ability to colonize a wide range of climatic and edaphic conditions is epitomized by its occurrence in East Africa where it is found at altitudes of 0-1740 metres above sea level (Brenan, 1967). Though probably less important than the related weeds, S. obtusifolia and S. tora, S. occidentalis has the potential to become a weed of more widespread significance. In the USA it is on the regulated invasive list for Florida (Invasive Plant Atlas of the United States, 2016).