These plants often have an unpleasant appearance, which is not suitable to the appearance of the lawn. Also, being annual, they often die in the winter, leaving real holes in the lawn.
There are herbicides that discourage or even stop the development of these plants. These are chemicals that are absorbed by the leaf surfaces of broad-leaved weeds, while leaving the narrow-leafed plants, including the most common species in the lawn, undisturbed.
Act when weeds are visible and well developed in the lawn. The application must be made with the lawn dry, and it is good to make sure that you have covered the entire leaf surface of plants to be weeded: you typically use a shoulder pump.
It is possible to colour the mixture of herbicide and water, so as to be better able to see which parts of the lawn were sprayed.
Weeds treated with these products dry out completely within a few days, and can be removed with ease, using a rake with thick teeth.