In 1909 Mimosa invisa was found first in Malesia by Dr. G. Roepke, then attached to the Central Experiment Station at Salatiga, Central Java, who spotted this American weed introduced on Mt Lawu. He used it for groundcover in some estates and since that time it became very popular and common, up to c. 600 m over Java. It shows a vigorous growth forming dense thickets at the expense of other plants which are suffocated and suppressed. In areas subject to a strong dry season it is limited to moist depressions and streambanks, under everwet climatic conditions it is found in abundance in the same moist places but also in dryland localities (1). It is also very common in Sumatra and it was especiallyutilized in the tobacco fields in Deli as a groundcover (and green manure) at the suggestion of the late Dr. de Bussy because of two reasons: Its vigorous mono-dominant growth and the fact that it is resistant against bacterial slime disease with which so many Indonesian soils are infected made it a most desirable acquisition, because during the fallow period of the Deli tobacco fields it prohibited the multiplication of Bacterium solanacearum on various other Solanums and other plants susceptible to this.