Gardening, Lawn Maintenance, and Landscaping Articles written by Kim Lewey

Turf Disease: Even With Your Best Efforts

A common misunderstanding for many homeowners that take proper care of their lawns is that turffertilization will eliminate all turfproblems. Therefore, when turf disease hits their lawn, it can be very upsetting. There are solutions that can correct turf disease, but can be costly, especially if left uncorrected over time.

What is turf disease? To explain properly, let’s eliminate what it’s not. “Weeds” are not disease. Common weeds like crabgrass and chickweed are simply plants that grow where they are not intended. The most common turfdiseases in the Triangle of North Carolina are caused by fungi and nematodes. Fungi are spread by spores and may cause root rot. Nematodes are commonly called roundworms and feed on the roots.

There are over 100 diseases that affect turfareas in North Carolina; the most common in the Triangle are Brown Patch and the less common Pythium Blight. Rhizoctonia solani, or Brown Patch as it is commonly called, looks like dying or over-watered patches of grass with its tan, brown, or yellow appearance. Symptoms appear between May and September, appear as irregular circular patches, and may have dark “smoke” rings around the edges in wet turf. Hot, humid weather, over watering, and high nitrogen fertilization are the main causes of brown patch. Fescue is the grass typically affected.

Pythium aphanidermatum, or Pythium Blight as it is commonly called, is seen as small, wet, irregularly-shaped patches with a spider-web effect that may start at 1-4 inches in diameter but can grow to 1-10 feet. Symptoms appear between June and August and can spread quickly in warm, excessively humid weather and may be more severe under high nitrogen fertilization. Cool season grasses like fescue are affected.

If you want to treat the disease yourself, there is an over-the-counter Bayleton Fungicide* that you can apply with a typical longevity of 7-10 days. You can also hire a licensed pesticide contractor to apply a treatment called Heritage Fungicide. This treatment is a controlled fungicide that lasts 28 days. The weather will dictate the number of treatments necessary to eliminate the disease, especially humid weather, but typically two or three controlled treatments are necessary to kill the fungus.

Can you prevent turf disease? Well… that is a loaded question. If your grass has been affected by turf disease before, it is more susceptible to reappearance each year. Also, properties with lots of trees with shade and limited sunlight and stagnant air patterns are more susceptible to turf disease. Likewise, free-flowing air properties typically do not develop turf disease.

Overall, Brown Patch is the most prevalent turf disease found in the Triangle. If left untreated, it will spread in hot temperatures and humidity conducive to its spread, but will disappear over time once temperatures in the evening reach 65 degrees or below, regardless of the humidity or daytime heat. In contrast, if Pythium Blight is left untreated, it can kill your grass.

Equipping yourself about your choices is the best way to make informed decisions about your lawn.

*Bayleton Fungicide has not been tested nor is endorsed by the author of this article.
References from www.turffiles.ncsu.edu

Reprinted with permission from Boom! Magazine, May 2010