What are the spots in my lawn?

If your seeing spots in your lawn this time of year, the Culprit is likely Red Thread! Not to worry, we have all you need to know in this post.

What is Red Thread?

The term “Red Thread” refers to a common lawn disease caused by a fungus called Laetisaria fuciformis. It gets its name from the thin, red or pink threads that develop on grass blades. Red Thread is most prevalent in cool, humid climates and can affect various types of grass, including fine fescues, ryegrass, and Kentucky bluegrass. (Typical for New England)

The symptoms of Red Thread usually appear as irregularly shaped patches of turfgrass that turn brown or tan. Upon closer inspection, you may notice small, thread-like structures sticking out from the grass blades. These threads are the reproductive structures of the fungus.

Red Thread tends to thrive in conditions where the grass is weakened, such as when the soil is low in nitrogen or during periods of excessive moisture. Overcrowding, poor drainage, and excessive thatch can also contribute to its development. It is not usually a severe disease and rarely kills the grass, but it can cause unsightly patches and weaken the overall health of your lawn.

Red Thread typically subsides and goes away when drier conditions prevail. When the weather becomes warmer and drier, the conditions become less favorable for the growth and spread of the fungus.

During dry periods, the fungus struggles to survive and reproduce, leading to a decline in its activity. As a result, the symptoms of Red Thread gradually diminish, and the disease naturally recedes. This is why Red Thread is often considered a relatively minor and temporary issue in lawns.

However, it’s important to note that even though Red Thread may disappear on its own when dryer conditions arrive, the underlying factors that contributed to its development should still be addressed. Taking steps to improve lawn health, such as proper watering, fertilization, and maintenance practices, can help prevent future outbreaks of Red Thread and other lawn diseases.