Integrated Pest Management (or "IPM") is an environmentally-friendly way to keep your landscape healthy. It keeps chemical controls to a minimum and focuses on more natural methods of controlling pests and disease.
Rutgers Cooperative Extension issues a monthly IPM newsletter with a lot of valuable information on this topic.
IPM is a much better way to care for your landscape than "cover sprays" which over-use chemical pesticides and kill beneficial insects as well as harmful ones. What we've found is this: if you try to kill everything, the harmful insects eventually win out -- and your property (and our environment) lose.