When it comes to maintaining a beautiful lawn, sod is a quick and effective solution for many homeowners. However, sod is not immune to diseases, and if left unchecked, these issues can destroy even the most well-kept lawns. Common sod diseases like Gray Leaf Spot, Leaf Spot, and Necrotic Ring Spot can turn your lush green lawn into a patchy, discolored mess. Understanding these diseases, their causes, and their symptoms can help you catch problems early and take the right steps to protect your lawn from long-term damage.
01. Gray Leaf Spot
Description: Gray Leaf Spot, a common fungal disease affecting warm-season grass varieties, is widespread in the USA. Found mostly in warm and humid places, the disease affects grass variants like Tall Fescue, St. Augustine, Bermuda, Zoysia, etc. The initial sign is tan-colored lesions with circular or oval shapes on the turf’s leaf blades. The spots, which have purplish or brown borders, appear on the turf’s leaf blades.
In extreme cases, lesions grow on stems and leaf sheaths. Those leaves wither and die quite soon.
As the disease progresses, the affected grass thins out and looks brown. This can affect a large part of the lawn. Without proper treatment, the damage can become severe.
Causes: The fungus named Pyricularia grisea causes Gray Leaf Spot. It thrives in regions with warm, rainy climates.
02. Leaf Spot
Description: Leaf Spot is a disease presents symptoms similar to Melting Out. Turf affected by Leaf Spot shows small circular spots. These spots are usually tan or brown-hued. The borders can be purplish or reddish. As the disease spreads, these spots get larger and they often merge. The grass blades become brownish or yellow before dying.
Causes: Leaf Spot is caused by a pathogen. It is often observed during the hottest days of summer.
03. Melting Out
Description: Melting Out disease may resemble another turfgrass disease called Leaf Spot. At the initial stage of this disease, grass blades show discolored spots. With time, the fungus gets into the plant’s inner tissues. The roots and crown are attacked. Affected turf becomes thin, shabby, and develops a yellowish hue. Some patches of grass die early. While raking the impacted areas, discarding the dead grass plants is easy. This disease can affect most cool-season grasses, but it causes the most damage in warm-season grasses like zoysia grass and Bermuda grass.
Causes: The pathogen that causes Melting Out thrives in wet and cool climates.
04. Necrotic Ring Spot
Description: Necrotic Ring Spot mostly affects cool-season turfgrass like Fine Fescue, Perennial Ryegrass, and Kentucky Bluegrass. This fungal disease affects the soil. The affected dead grass patches form a circular pattern, with a brownish-yellow ring encircling a center that appears normal. The ring size can vary, though. The disease is also known as “Frog Eye” for its unique shape.
Causes: Necrotic Ring Spot symptoms show up mostly in the cool spring months. But the fungus can stay active so the symptoms can be seen in the growing season, too. The heat and drought-caused stress can intensify its signs. This may make the symptoms prominent in dry and hot summer days.
05. Powdery Mildew
Descriptions: Powdery Mildew is capable of infecting almost any turfgrass but this fungal disease is seen mostly in variants like Fescues, Bentgrass, and Annual Bluegrass. The fungus leads to the formation of a grayish or white powdery coating on the stems and leaves. It drains the plant tissue and damages the plant. The affected leaves often become yellow or brown. The affected grass becomes weak and stunted.
Causes: Powdery Mildew thrives in cool, humid climates. So, it affects turf grass in the fall and spring months as the average temperature hovers between 55° to 70°F. In heavily shaded zones, the disease can spread quickly. It also thrives in low light and poor air circulation gives it momentum.
Conclusion
Sod diseases can quickly turn a healthy lawn into an unsightly yard, but with proper knowledge and timely action, most problems can be managed or even prevented. Recognizing the symptoms of diseases like Powdery Mildew, Melting Out, and Gray Leaf Spot is crucial to stopping them from spreading. By understanding the causes, monitoring your lawn regularly, and using proper lawn care practices, you can help keep your sod in good health.