Weeds represent an important variable in maize production, both economically and ecologically. Weed competition can cause yield reductions of up to 70% in maize grain yields (Teasdale, 1995). During the first half of this century the most common methods of weed control were rotary hoeing and interrow cultivation. The effectiveness of interrow cultivation in suppressing weed density in maize is well documented (Wilson, 1993). However, cultivation represents an additional cost for the producer due to the consumption of fossil fuels (Lybecker et al., 1988).