Each chemical has a place in lawn care and may be essential to correct a major problem, but before using them we should take the time to determine why the weed problem exists.
Turf grasses tend to be very good competitors when given a proper growing environment.
Often the weeds themselves will indicate the problem and guide the correction process. Lawn areas with sparse grass and moss growing on the soil surface may indicate several environmental problems. Heavy shade in the area may be weakening the grass and providing a more desirable situation for the moss growth. If shade is not the problem, moss often is a first indicator that the soil is infertile and too acidic for the grass species. Poor drainage, possibly due to soil compaction, also favors the moss.