Abstract

Three experiments were carried out in the central area of the state of Veracruz, Mexico, during the Fall-Winter seasons of 1989-90, 1991-92 and 1992-93. The main objective was to determine the effect of the time and type of weeding on the yield of residual moisture growing beans. Twelve treatments, arranged in a CRBD with four replications were evaluated. Treatments consisted in hoeing at different times. In some treatments, hoeing was complemented with hand-weeding. The highest grain yields were obtained when the weeds were eliminated at least in two ocations during the early stages of development of the crop. The yield of these treatments was significantly higher than that obtained with the traditional weeding practice (hoeing at 25 days after emergence).Handweeding after hoeing increased grain yields at high weed densities,but when the weed density was not very high, handweeding after hoeing made no difference. The increase in grain yield obtained when two weeding operations were performed instead of one, was sufficient to cover for the expenses of this additional practice and to generate economic profits.