The Eupatoriun adenophorum Spreng appeared in southern Yunnan in 1960's is the weeds of the wasteland. In order to control it's harm a series of basic researches from the seed ecology to repjoductive characters was carried out. The effective preventive measures were put forword. The paper is based on autecolo -gy. Some results are reported as follows.1. The tiny seeds disperse mainly in the topsoil lees than 0.5cm deep. The rate of seed-sprouting is about 50%. They germinate best in the damp soils on pH.5-6...