I found a litte in my current lawn and it was a single tiny strand with little yellow flowers. If your lawn is in serious need of fertilizer, use a third of what the package recommends every three weeks in the spring and fall. Otherwise, use half of what the package recommends at the beginning of spring and the beginning of fall. Since the roots are in the top inch or two of soil, a hot day will quickly dry the soil and much of the grass will brown. This will force your grass roots to go deep into the soil. As the top few inches of soil becomes bone dry, the weeds and weed seedlings up there die while the grass still enjoys moisture from a little deeper.
You will occassionally see a little once in a while, but it is kinda pretty when it isn’t taking over your drought tolerant grass lawn. When it’s taking over, it will choke out grass and make flat mats about a foot in diameter.
It is my opinion that when it comes to , mowing high is, by far, the most important thing. Finally, when mowing, be sure to leave the clippings on the lawn. It adds organic matter and nutrients back into the soil. If you don’t leave the clippings, your soil will begin to look more like “dirt” than soil. Soon it will be a form of cement that nothing will grow in and you will have the world’s most pitiful lawn.