Minimum tillage technologies for the establishment of Brachiaria decumbens on the northwestern costal plains of Puerto Rico

Three minimum soil tillage techniques for Brachiaria decumbens establishment were studied in comparison with the conventional way of establishing pastures in Puerto Rico. The minimum tillage establishment technique using one superficial harrow disk pass, without any previous glyphosate application (Treatment 2), showed an extremely poor pasture germination and coverage. This finding clearly proved that the application of minimum tillage technologies, without the previous use of glyphosate, produced an increment of weed population above that of grasses. Conventional planting without glyphosate (Treatment 1 ), non tillage with previous application of glyphosate (Treatment 3), and one superficial harrow disking with previous application of glyphosate (Treatment 4) showed no significant (P<0.05) differences in soil coverture at four months after the establishment. Similarly, the average available dry matter yield during the three consecutive grazings after establishment showed no significant (P<0.05) differences among the three above mentioned treatments. From the agronomic perspective the three treatments were similar; minimum tillage technologies did not show any advantage over the conventional planting system. In terms of the projected costs for pasture establishment associated with these treatments, no significant differences (P<0.05) were observed among the three. Total cost for treatment 1 was $577.5/ha, followed by treatment 3 with $478/ha, and treatment four with $435.7/ha.