Cultural Methods of Control
The most effective method of controlling lawn weeds is to maintain a dense and vigorously growing turf cover. Increasing numbers of weeds are often an indication of problems in the grass plant’s environment that create less than favorable conditions for it to grow. Killing the weeds without correcting the underlying problem will lead to unsatisfactory results. For example, increasing quantities of prostrate knotweed is usually an indication of increasing soil compaction. Control of knotweed without correction of the soil compaction will only lead to sparse grass cover until the area is again invaded by weeds that grow in compacted soil.
Often, lawn weeds can be controlled simply by altering the cultural practices to favor the grass plants rather than the weeds. Cultural controls may include raising (or lowering) the mowing height, changing the frequency of mowing, lengthening (or shortening) the period between irrigations, increasing (or decreasing) the application of fertilizer, or aerifying the soil.
Hand weeding or pulling weeds is also an effective way to eradicate weeds from small lawn areas. The best time to pull weeds is after a good rain or thorough irrigation. This control is very economical (but labor intensive) (Fig. 10.6). It avoids needlessly applying herbicides over the whole lawn for only a few weeds.
Figure 10.6. Mechanical control – hand weeding.
There are also several tools on the market that will aid in hand pulling weeds (Fig. 10.7).
Figure 10.7. Tools to aid in mechanical weed removal.
At some point, even with the best of practices, there may be a need for the use of a chemical herbicide to control a certain weed or weed population. A combination of proper cultural practices plus prudent use of herbicides is a good approach to controlling lawn weeds effectively.
Proceed to Types of Herbicides