All lawns can be susceptible to disease and insects. Following good cultural practices in regards to mowing, watering, fertilization, aeration and overseeding will lead to a thick lush lawn. However, at certain times of the year and under certain climatic conditions, insects and diseases symptoms can begin to show.
Symptoms can show gradually or become severe overnight.
It is not important to be able to diagnose what the problem is. It is however important to be diligent in your observations so you can notice the problem promptly and get a lawn professional to diagnose the exact problem and offer a cure.
As soon as you see something that looks unusual, contact someone to help as soon as possible.
With some insect problems, such as grubs, a preventative insecticide program can be made to help control insect damage.