Answer: If your lawn is new, you won't need to thatch for a few years. Thatch is a build up of dead stolons, stems and leaves. All lawns have thatch but when the thatch layer gets too thick it can slow or stop water penetration. When the thatch reaches 3/4 of an inch, it's time to dethatch. That won't be for a few years.
The insects you describe sound like white flies. You can control them with sprays of insecticidal soap. For best results, spray in the early morning or at dusk when most of the pests are resting. Be sure to spray both the upper and lower leaf surfaces. Repeat sprays will be necessary. Best wishes with your garden.
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