Also know that there are just some spots in which grass will not grow well. At the base of a tree, you might have better luck with wood chips or a shade loving ornamental plant like ivy, periwinkle or pachysandra. Monitor and identify problem areas. Serious ongoing pest problems are often a sign that your lawn is not getting what it needs and may be a symptom of an underlying problem. You may need to correct the underlying problem to reduce the chance that the pest will reappear.
All pesticides are toxic by definition.
Even when applied properly, they can also kill earthworms and other beneficial organisms, disrupting the ecological balance of your lawn. Biological control means using natural enemies to pests. Horticultural control involves the use of gardening methods like mowing high to shade out weeds. Use appropriate controls, and treat only the problem that exists. They are one of nature s best biological insect controllers.