Weeds are the plants, which grow where they are not wanted.

It is difficult to define such plant, for what is paste in one part of country may be desirable in another. Further, vary in their amounts of their harmfulness.

Thus weeds can be defined in many ways but it is only the conception, which should be clear for understanding them. " The weeds thus suggests that they are undesirable, ugly unwanted plants often prolific and persistent, noxious and harmful in potentialities." Such plants are injurious for crop plants, interfere with Agril – operations, increase labour, add to the cost of cultivation, impair the quality of farm produced and finally reduce the crop yields. Such plants are known as weeds.

In short, "A plant whose potentiality for farm are greater than its potentiality for good.".

(Weed Control)