The study looked at how different ways of preparing soil affect the amount of wheat grown and the level of weeds in the field. They tested three methods: using a plough, a rotary harrow, or a paraplow and chisel. They found that using less soil tillage led to more weeds in the wheat field, especially perennial weeds. The amount of wheat grown was similar with the paraplow and chisel, but lower with the rotary harrow. This means that using different soil tillage methods can impact both the amount of wheat grown and the number of weeds in the field.