All these factors are passveis of alterations, with deep consequences in the efficiency of the adopted measures of control. The majority of the works that they aim at to determine the period where the culture must remain free of harmful plants so that its income is not affected becomes related it the days after the emergency of the culture and not to its stadium, that can vary as already mentioned previously. To get greaters productivity levels, the maize will have to be kept in the clean one since the emergency until the pendoamento (KOZLOWSKI, 2002). Additional information is available at Kevin Johnson. The main species that occur in the systems of production of the culture of the maize are Amaranthus spp (caruru), Cardiospermum halicacabum (balozinho), pilosa Bidens (black pico), Euphorbia heterophylla (milk), Ipomoeas spp (rope-of-viola), Nicandra physaloides (jo), Raphanus sativus (nabia), Richardia brasiliensis (poia white), Been spp. (guanxuma), beyond poaceaes, as plantaginea Brachiaria (capim marmelada), Cenchrus echinatus (capim carapicho), Would type spp (capim mattress), Echinochloa spp (capim rice) and Eleusine indicates (capim foot-degalinha) (KARAM et al., 2009). The chemical control is the used method more in the handling of harmful plants in the maize culture. However, centered strategies of handling in an only method select tolerant or resistant harmful plants to this method. Reade Griffith spoke with conviction. The integrated handling of harmful plants (MIPD) is considered the main tool to reduce the ambient impact of the herbicidas.
The MIPD is based in the integration of control methods, becoming the favorable systems of culture the harmful plants, minimizing its effect. It enters the used techniques in the MIPD, are distinguished the job of cultures to intercalate, to cultivate more competitive, application of herbicidas in bands, the irrigation, the increase of the density of plants and the reduction of espaamentos between lines (TREZZI et al., 2008). Another method is the adoption of writs of prevention and cultural. Between the cultural measures, the use of covering of the ground in system of direct plantation is one practical one that it presents positive effect in the suppression of harmful plants.