Brown Patch in your lawn?
October 1, 2018
At the top of the list of common fungal diseases that attack lawns in DFW, is brown patch. This persistent disease can be unsightly and frustrating.
During the moderate-to-cool temperatures of spring and fall, brown patch becomes active and attacks grass blades. This disease is typically a problem on St. Augustine lawns, which is most susceptible. However, it can and does attack Zoysia grass as well. If you have a Bermuda lawn you're in luck - Bermudagrass isn't susceptible.
Brown patch is commonly mistaken for several other common issues such as Take-all root rot, gray leaf spot, and even grubs or chinch bugs. Brown patch isn't the most difficult disease to control, but it can quickly create major visual damage that persists for weeks to months. Rarely does brown patch cause complete die back of St. Augustine where re-sodding would be necessary. This is because it only attacks the blades of grass rather than the runner/stolon or roots. There are exceptions however: if your lawn is stressed due to too much shade, then brown patch can hasten it's overall demise.
When identifying brown patch disease, the first visible signal at a glance are circular patches in the lawn that are beginning to yellow. Take a close look at the individual leaf blades of your grass. You'll also see darker sunken areas which are the fungal mat of the disease. If you pull on the yellowing blades and they pull away from the stolon (surface runners) without resistance, then you probably have a brown patch infection.
As the disease starts to go dormant, the blade will turn a light brown straw color. Brown Patch tends to go dormant in cold and freezing temperatures.
How to Control Brown Patch
Brown patch can be successfully suppressed organically with horticultural corn meal which makes growing conditions unsuitable for certain types of fungal diseases. Brown Patch is NOT treated with corn gluten meal which is marketed as an organic pre-emergent (not for disease control). Brown Patch can also be treated successfully with a chemical fungicides but we find using natural treatments can be just as successful and are easier on the environment.
Once Brown Patch infects your lawn it will most likely reoccur seasonally. In these situations, preventive measures should be taken in early spring and/or fall. Preventative treatments should be coupled with good watering techniques (don't overwater!) Brown patch thrives in wet conditions, so if you're overwatering your lawn you can encourage it's spread.
“Defer to a bit of dehydration in the grass during the spring and fall seasons rather than over-watering like it’s summer time.” Steve Clary, Turf Healthcare Specialist
Mowers easily spread brown patch disease from one yard to the next. If you're using a mowing service there's a good chance they don't clean their mowers between yards, and will spread it to your St. Augustine lawn when the disease is active.
Posted: October 1, 2018