Once the active ingredient of the herbicide has been developed it has to be presented to the user in a format which will be both economical and effective. Many companies provide the growers with a herbicide in different formulations depending on the application. The different formulations are used in order to vary the volatility, solubility, [...]

Characteristics of each chemical group differs from each other so it is important to know to what group a herbicide belongs before applying it to a plant. Active ingredient will also provide an indication of lead time before a crop can he safely harvested.  There are so many ways of classifying herbicides that we decided [...]

General classification of weeds Most farmers use a different method of classifying weeds since it is easier to understand and separate each weed from another in order to control them. Classification according to growth season length Annuals: These weeds complete their life-cycle in one year. Due to the abundance of dormant seed and fast growth of [...]

Biology of weeds is important since it covers all aspects of their establishment, growth and reproduction.  All climatic factors have a significant effect on biological processes.  A good knowledge of the biology of weeds will ensure that the grower and researcher will be able to apply technology correctly to control any weed problem. The succession process [...]

As the pressure increases to develop safer and more economical herbicides, the Government is forced to either withdraw or restrict some of the older chemicals.  Table 3 provides a list of the restricted and banned herbicides used in South Africa.  It is important to have this list handy so that anybody using these chemicals can be [...]

Application and Herbicide drift If pressure is used to apply herbicides, there will always be some herbicide drift through the air.  If there is no commercial crop in the vicinity, spray drift will have no effect, however, when weeds have to be controlled between rows of a commercial crop, any spray drift might cause considerable damage. [...]

It sounds strange to think that weeds do have advantages.  This way of thinking is made difficult by our perception and definition that weeds do not have any use.  Plants classified as weeds are often removed without evaluating the environment first.  By removing one type of weed in an area does not prevent another, even worse [...]

A weed is a plant which is growing where it is not desired, or a plant out of place.  For instance, maize growing in a peanut field is a weed. Wheat growing in a cotton field is a weed.  A weed can be any plant type which is not contributing to the profitability of the farm [...]