This work was carried out at the Sugarcane Center (Centro de Cana IAC), Ribeirão Preto-SP, to evaluate the effectiveness of fusel oil alone and mixed with glyphosate applied at late weed post-emergence of a natural community. The experimental design was randomized blocks, with 13 treatments and 4 repetitions, totaling 52 plots 3x3m each. Application of the treatments was accomplished on 03/22/2006, with pressurized back sprayer. The control percentages were evaluated at 14, 21, 28, 35 and 42 days after treatment (DAA) and weed dry matter was obtained by using a square 0.5 x 0.5 m sorted two times on the plots at 42 DAA. The less satisfactory results under the control at the end of the experiment were when fusel oil was applied alone. The lack of 100% control in the main treatments evaluated was due to the presence of the weeds Commelina and Cyperus spp., which were more tolerant to herbicide application. The control efficiency obtained by using fusel oil was no more than 20% at 42 DAA.
by-product; control; herbicide
