Soil acidity correction and control of sape-grass

A field experiment was conducted to determine the effect of acid soil correction, on the control of the sape (Imperata brasiliensis), a grass type weed of pasture. A molasses grass (Melinis minutiflora) pasture in a red-yellow latosol, having a high proportion of "sape" was used. Treatments consisted of five levels of dolomite limestone (0, 1, 2, 4 and 6 t/ha) incorporated by hand using a garden tool to the top 20 cm of soil following a mechanical tillage of the plots (disking). An additional treatment without disking and without lime was adopted. The experimental design was randomized blocks with four replications. During the 33 months of the experimental period, three harvests and two soil samplings were performed. There were no effects of lime rates on the dry matter yield of both sape and the other species (molasses grass, Brachiaria decumbens and broad leaf weeds), despite of the changes in the soil chemical characteristics. The correction of acid soils, when associated with the correction of main nutritional deficiencies, can control the weed "sape" by improving the forage growth.