Do you have Dollar Spot in your lawn?

While we all love the return of fall weather, so do all the fungal diseases that attack our lawns! We recently blogged aboutBrown Patch in fall lawns. Now we turn our attention to Dollar Spot. This is a fungal disease caused by Sclerotinia homeocarpa, which typically turns up in Bermuda and Zoysia grass lawns.

Dollar spot can show up in spring through fall, but is a bigger problem during periods of high moisture or humidity; and when days are warm and nights are cool. So that’s, right now! The disease gets spread around your lawn by water, lawn mowers, trimmers and your shoes. 

So how do spot this pesky disease? Be on the lookout for dollar-sized round spots in the lawn that are brown or tan colored. If you allow your lawn to grow taller, then you may see larger dead spots. This can sometimes make it difficult as a homeowner to distinguish Dollar Spot from Brown Patch. If you’re not sure, look for light-tan lesions on the edges of the grass blade. These lesions will have a reddish-brown border around them. Early in the day, you might also find the stringy mycelium of the fungus growing around the infected area. 

So what causes this disease? Typically, lawns that have been stressed by too little water are more susceptible to the disease once moisture and humidity levels rise in spring or fall. Low Nitrogen and Potassium levels in the soil can also make the disease worse. 

Low soil moisture has been reported to enhance dollar spot activity, but moisture from dew, light rain or irrigation must be present on the foliage for the disease to develop. Excess thatch (un-decomposed material) and compacted soils are also a problem. 

Be sure to have your lawn aerated to stimulate microbial growth, if you’ve not done so in a while. This will aid in the breakdown of excess thatch. Be sure to water your lawns deeply and infrequently, versus light frequent waterings. Be sure tomow your species of grass at its recommended height and keep your soil and lawn fed properly. Organic fungicides can also be used to control the disease.

dollar spot, fungal disease, lawn, brown spots, organic, fungicide, Soils Alive, Dallas, Texas