Dollar spot is a lawn disease marked by brown spots in your yard — not a new rival to your favorite dollar store.
But what is dollar spot? How can you tell if you have dollar spot? And what can you do to get rid of it? We’ll cover all that and more in this article. A little change in your watering methods may be all you need to turn those brown spots green.
What is Dollar Spot?
Dollar spot is caused by the Clarireedia jacksonii fungus, formerly known as Sclerotinia homoeocarpa. It creates discolored, bleached-brown and tan spots on lawns and golf courses. This turfgrass disease gets its name because the spots typically start around the size of a silver dollar coin.
Dollar spot is common in the spring when night temperatures are consistently higher than 50 degrees.
How Do You Identify Dollar Spot?
Many other lawn diseases can create symptoms that resemble dollar spot. These characteristics will help you identify if you have dollar spot:
- Dollar spots on lawns can expand from their original size to around 6 inches wide in diameter.
- Leaf blades affected by dollar spot will typically remain upright rather than wilt, and have tan or straw-colored hourglass lesions with a dark brown border around them.
- As the fungal disease worsens, the upper part of grass blades will begin to die off, and individual spots may merge to create large affected areas in your yard.
- In the morning, when dew is present, you may see fuzzy white mycelium roots in your grass.
What Causes Dollar Spot?
Dollar spot is very common, and can be caused by many factors. These characteristics can leave a lawn prone to the disease:
- Drought stress
- Low mowing
- Excessive thatch
- Cool nights above 50 degrees with lots of moisture, such as heavy dew, high humidity, and rainy and overcast weather. Longer periods of dew will intensify dollar spot infection.
- Nutrient-deficient soils, particularly dry soils or those with low nitrogen
Once it’s there, dollar spot can also be spread throughout your yard by lawn mowers, wind, and water.
What Grass Types are Most Susceptible to Dollar Spot?
All varieties of warm-season and cool-season grass are prone to dollar spot, and many cool-season grasses are particularly at risk for this disease. Choosing a resistant grass cultivar is particularly important for dollar spot prevention.
Bentgrass and Kentucky bluegrass are most likely to have issues with dollar spot. For warm-season grasses, bermudagrass, Zoysia, and seashore paspalum are particularly at risk. Perennial ryegrass and tall fescue are more resistant to dollar spot than other grasses.
How to Get Rid of Dollar Spot
To get rid of dollar spot:
- Water grass deeply and infrequently to avoid moisture stress, and plan to water early in the morning, before 10 a.m.
- Dethatch and aerate your lawn to break up the dense thatch layer.
- Prune shrubs and trees. Reducing shade will improve air circulation in your yard and reduce dollar spot infection.
- Apply fertilizer or compost to increase nutrients in your soil.
- Biofungicides, living organisms that feed on lawn diseases, can help control dollar spot naturally.
- Overseed with new turfgrass if the disease causes lasting damage to your yard.
Note: Dollar spot is resistant to many fungicides, so they’re primarily recommended as a preventative measure, but they may also help control an ongoing infection. Mowing or rolling grass can also prevent dollar spot, but both can spread the disease once it is present.
FAQ About Dollar Spot
Dollar spot will not go away on its own, but there are plenty of ways to treat it. It’s better to treat it early before the disease spreads throughout your yard.
Lots of fungicides can treat dollar spot. Here are a few of the most effective:
Dollar spot develops resistance to fungicides quickly, so it’s best to use it as a preventative treatment and rotate often which variety you use. Fungicides should be applied at high rates and short application periods starting in early spring.
Most lawns will recover from dollar spot with a little bit of hands-on care, as long as you act in time to treat it.
Get Rid of Spots, Not Dollars
If your lawn is struggling with dollar spot, it’s important to tackle the problem as soon as possible.
With a little time and care, your yard should recover from the lawn disease, but don’t let it go until it’s too late. Reviving or replacing a yard damaged by dollar spot will only get more expensive with time.
If you need help handling a case of dollar spot infection or preventing dollar spot from coming back – or just regular mowing, trimming, and edging – just call one of our lawn care professionals.
Main photo credit: Scot Nelson / Flickr / Public domain