Dollar Spot Fungus: Causes, Symptoms, Prevention and Treatment

Do you notice small, circular patches on your lawn that turn yellow or brown? If yes, then it may be a sign of Dollar Spot fungus. This common lawn disease is caused by a fungal pathogen called Sclerotinia homoeocarpa. It can affect different types of turfgrass, including Bermuda grass, Ryegrass, and Bentgrass. In this article, we will discuss the causes, symptoms, prevention, and treatment of Dollar Spot fungus.

The Causes of Dollar Spot Fungus

Dollar Spot fungus thrives in warm and humid environments, especially when the temperature ranges from 60-85°F. The fungus can overwinter in infected plant debris or soil, and it can spread through wind, water, or contaminated equipment. Poor soil conditions, such as low nitrogen levels, can also contribute to the development of Dollar Spot fungus. Stress factors like drought, inadequate irrigation, and excessive thatch buildup can weaken turfgrass and make it more susceptible to the disease.

The Symptoms of Dollar Spot Fungus

Dollar Spot fungus typically appears as small, silver-dollar sized patches on the lawn. These patches can gradually increase in size, and they usually have a straw-colored or tan center with reddish-brown margins. The leaves of the affected turfgrass become bleached or whitish and have lesions or sunken spots. If left untreated, the patches can merge and cover large areas of the lawn, resulting in severe damage to the turfgrass.

Prevention of Dollar Spot Fungus

Preventing Dollar Spot fungus involves maintaining healthy soil conditions and proper lawn care practices. Here are some tips:

• Aerate the soil regularly to improve air circulation and water absorption
• Dethatch the lawn to prevent excess buildup of organic matter that can harbor the fungus
• Fertilize the lawn with a balanced nitrogen-rich fertilizer to promote strong root growth and resistance to disease
• Water deeply and infrequently to encourage deep root growth and reduce moisture on the surface level, which can create favorable conditions for the fungus.
• Mow the lawn at the recommended height for your turfgrass species and avoid cutting more than one-third of the leaf blade at once.
• Clean lawn equipment after each use to avoid spreading the fungus to other areas of the lawn.

Treatment of Dollar Spot Fungus

If your lawn is already infected with Dollar Spot fungus, there are several treatment options available:

• Fungicides: Apply fungicides specifically labeled for Dollar Spot fungus according to the manufacturer's instructions. Repeat applications may be necessary, especially during periods of high humidity and temperature.
• Cultural practices: Increase the frequency of watering and fertilizing, reduce thatch buildup, and improve soil drainage to create unfavorable conditions for the fungus.
• Reseeding: If the damage is severe, reseeding the affected areas may be necessary to restore the health of the lawn.

Close-up of Dollar Spot Fungus

Dollar Spot fungus can cause unsightly damage to your lawn if left untreated. By following preventive measures and treating the disease promptly, you can restore the health and beauty of your turfgrass. Remember to maintain proper lawn care practices, monitor weather conditions, and consult a professional if needed. With these steps, you can keep your lawn free from Dollar Spot fungus and other lawn diseases.

Dollar Spot Fungus, Lawn Disease, Lawn Care, Turfgrass Maintenance, Fungal Pathogens