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Sumatran fleabane is an important weed in Brazilian crop production systems due to glyphosate resistance and broad adaptation to no-till environments, mainly in the crop succession with soybean sowed in first-season (September to February) followed by maize in second-season (February to June). The fallow period between maize harvest and the next soybean sowing allows Sumatran fleabane to emerge and grow. On the other side, fallow is a suitable moment for Sumatran fleabane control because plants are more susceptible to herbicide in initial stages of growth. In this study, the aim was to evaluate the effectiveness on combined burndown + residual herbicide treatments to control Sumatran fleabane during fallow, after maize harvest. Two experiments were carried out in Campina da Lagoa (PR) and Floresta (PR) and treatments consisted of combinations of herbicides to provide control of emerged plants of Sumatran fleabane (glyphosate + 2,4-D, MSMA and glufosinate), applied isolated or in tank mixes with residual herbicides (metsulfuron, chlorimuron, diclosulam, imazethapyr, imazaquin, flumioxazin, metribuzin, amicarbazone and isoxaflutole) which were expected to prevent the emergence and growth of new weed fluxes. At the time of herbicides application, Sumatran fleabane plants were no taller than 12 cm. Assessments on both efficacy and residual control were performed until soybean crop sowing (45 days after treatment). Glyphosate + 2,4-D mixture was efficient for burndown of Sumatran fleabane. For fallow periods of 45 days, all glyphosate + 2,4-D mixtures with residual herbicides were efficient for Sumatran fleabane control, providing less than 10 plants m-2 and a maximum plant height of 16 cm at soybean sowing date. [ABSTRACT FROM AUTHOR]