Grass control during production

Because of the Importance of weed parts as a trash component, weed and grass control during the production phase is extremely Important. It may be concluded (12) that if there is grass in the field, there is likely to be grass in the fiber. Broad-leaf-weed and grass control in the field provide, therefore, the first effective opportunity available to reduce the foreign matter content of ginned fiber. 

Control of NH3 loss during grassland production presents many problems. The most readily manipulated loss is that arising from land application of slurry. Injection effectively eliminates NH3 loss, as discussed above, and is sometimes reflected in increased efficiency of utilisation of the N applied (29). On grass/arable farms, application of slurry prior to ploughing or cultivation also increases N recovery by the following crop. However, the speed with which NH3 loss can occur requires that cultivation takes place almost immediately after application (29). 

On the other hand, the broad weed control spectrum of chloramben, which was introduced in 1959, brought with it widespread acceptance. As an over-the-row band for control of both broadleaf and grass weeds, cost was minimized. With good crop tolerance, chloramben dominated the early soybean herbicide market. During 1972, 85% of the product was applied as the granular formulation (Table 4.2). However, as application practices changed for the soybean crop, banded applications became an inconvenience. Herbicides such as metribuzin (a triazine herbicide), linuron, and bentazon, which could be applied as an affordable broadcast treatment, soon became products of choice, and the marketing of chloramben was eventually discontinued in 1990. 

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