author(s)
Nuru Seid Tehulie

abstract
Maize (Zea maize L.) is one of the major cereal crop produced worldwide after wheat and rice mainly as food for human and as animal feed .maize is the most sensitive crop to weed competition during its early growth stage and weed control is an important management practice for maize production that should be carried out to ensure optimum grain yield. Weeds compete with the corn plants for resources such as light, nutrients, space, and moisture, water, especially during that good weed control within the first 4 to 6 weeks after crops are planted is critical in order to avoid a yield reduction from weeds. The critical period for weed control (CPWC) is cried in the crop growth cycle during which weeds must be controlled to prevent yield losses .the maximum weed competition in maize occurs during the period of 40 to 45 week after sowing suggesting the importance of maintaining the field weed. Free during this critical period of weed competition. Weed competition is maximum during early stage of crop growth .Weed competition early in the season reduce yields more than late season competition. Although yield is not greatly reduced by late season weeds, they may case difficult in harvesting, low crop quality and reduce protein content. So, this paper is Review on Critical Period of Weed Competition and Management in Maize (Zea Mays, L) it can control optimum and minimum weed by using management method.