Q: I fight dollar spot disease in my yard every year. I’ve sprayed three times this summer and it hasn’t helped at all.

A: It is not easy to diagnose lawn diseases, even for professionals. It is true you could have dollar spot but there are a couple of other diseases that are similar and without a microscope, they are hard to tell apart. Although fungicide labels don’t admit it, each chemical controls different fungi differently. One chemical might control some fungi better but another chemical might control other fungi better. That’s why it’s important to know which fungus you have on your lawn: you have to match the fungicide with the disease. The best way to avoid lawn disease is to be sure your maintenance is perfect: watering, fertilizing, mowing height, etc. If you want to know exactly what disease you have, your local Extension office can give details on how to collect a sample.