A recent article featured in Popular Mechanics discusses various lawn diseases and methods of both treatment and prevention.

The article stresses that harmful grass pathogens are constantly present in every lawn and only awaiting the opportunity to become active. Combine a grass variety susceptible to a pathogen with the wrong weather conditions, and presto! Your lawn may soon blossom with harmful microorganisms.

The authors also point out that there are good fungi and bad fungi, how to spot each and how to foster the right kind. When a bad fungi becomes active, it may be spread by weather, grass clippings and even your lawn mower.

The best preventive measures against lawn diseases are:
1. Choosing the proper grass cultivar for your soil and weather conditions.
2. Maintaining a lawn which is well-aerated, has good drainage, and gets plenty of circulated air.
3. Diligent care in your methods of watering, fertilizing, and mowing.

The use of organic composts can help in the prevention of lawn diseases and the authors explain the best methods.

Spring, Summer, and Fall-specific lawn diseases are covered in great detail and well worth the read, as well as conditions such as Fairy Rings, Stripe Smut, Necrotic Ring Spots, and Dollar Spot.

You may read the entire article at Popular Mechanics, and this page features tips on diagnoses with accompanying photographs.