Summer Patch, Necrotic Ring Spot, and Brown Patch are root born diseases that make circles and frog eye shapes. Almost every lawn has had or does have these problems. These diseases are most evident in times of stress, like when it's dry and hot. Conditions such as excessive thatch, poor soil, sod installed over a poorly prepared site and poor cultural practices (mowing and watering) can give these fungus problems all they will need to do serious damage. In most cases, light to moderately damaged areas will recover with minimum long term damage. In severe cases, Fungicide treatments may be needed to stop the damage from getting any worse and rescue the rest of the lawn from infection. Treating light to moderately damaged lawns with a special organic fertilizer and aeration supresses disease by balancing out soil problems naturally, and is a very cost effective and environmentally friendly long term option.

Fungus Problems

There are many different types of fungus which grow in every lawn and it's unlikely that you could eliminate all disease causing fungi, and you wouldn't want to if you could. Many of the fungi that cause turf grass diseases are also important in nutrient cycling, especially in breakdown of thatch. However, if cultural conditions deteriorate these "beneficial" pathogens can cause serious problems.

Problematic Fungus:
What is it?

    There are several problematic types of fungus in our area. Some of the most common types include Summer Patch, Necrotic Ring Spot, and Brown patch. The damaged areas can appear as sunken spots of yellow turf that make patches or circles which are sometimes referred to as "frog eye". Damage can be aggravated with stress which can occur in many forms such as the wheels from the mower, which can leave what appear to be tracks of yellow turf behind a few days after it occurs.

Summer Patch:

    Summer Patch is caused by the soil-borne fungus called Mangaporthe Poae. It is commonly associated with grasslands and appears mostly in Bluegrass and Fine Fescue grasses, but can show up in other types of cool season grasses as well. It is a warm weather root disease and grows best in temps between 80-85 degrees Fh and can occur in turf from mid-June through September and reappears during times of hot weather.

Necrotic Ring Spot:

    Necrotic Ring Spot is caused by the Leptosphaeria korrae fungus and it is a cool weather root disease. Symptoms are nearly identical to summer patch, however, in contrast to summer patch Necrotic Ring Spot kills roots in the late spring when soil temps reach 65 degrees and continues through the summer with symptoms appearing in late June and July.

Brown Patch:

    Brown Patch is caused by fungus named Rhizactonia solani. It is active mostly in warm temperatures and symptoms begin to show under these conditions.

In Summary:

    These "patch diseases" are similar in appearance and management and will likely return to the same areas of the lawn every year. Unless steps are taken to change the conditions in the lawn which lead to the propagation of these diseases they will rapidly spread. For even more detailed information please visit the University of Illinois Extension.

Organic Fertilizer:

    By looking at the picture above, the results speak for themselves. Both yards are fertilized with Granular Time-Release Fertilizer, However, the yard on the left is fertilzed with Organic Granular Time-Release Fertilzer. Soil is more important to the overall health of your lawn than any other variable. It has been proven time and again that organics supress fungus and stimulate healthy micro-organisms. By accelerating and stimulating microbial life (the life blood of rich soil), you can reduce thatch maintenance, increase drought tolerance, and insure better long term health. Getting your soil closer to the optimum organic state will make a lasting difference.