Abstract
A comparison of three tillage methods: disc ploughing and harrowing once (Reduced Tillage); disc ploughing and harrowing twice (Conventional Tillage); and disc ploughing, harrowing twice and chisel ploughing (Conventional Deep Tillage), showed no significant differences in plant height of maize and yield of maize and cowpea on a heavy clay soil on the coast of Guyana. Deep tillage enhanced internal soil drainage in the wettest trial, and at low elevations in the field, but yield differences were not significant. The improvement of soil physical parameters due to tillage seems to be short-lived. The effect of soil elevation on soil moisture content, and growth and yield of maize was more pronounced than tillage method. The study showed that Reduced Tillage is just as effective as Conventional Tillage and Conventional Deep Tillage for maize and cowpea production on this soil type.
