Understanding Lawn Fungus
You have been working hard all year, making sure your lawn is summer-perfect, but there is something not quite right. Your lush grass is showing brown areas, or maybe the blades are looking a little limp. These are signs that your lawn may be fighting a fungal infestation, causing disease.
Central Indiana weather can seem unpredictable, these weather patterns are a driving force for Central Indiana’s most common turf diseases. With the exception of snow mold, these lawn diseases are most prevalent in the summer, where the long, hot, and humid days provide a perfect breeding ground. Thankfully, there are many things Central Indiana residents can do to prevent and control these diseases, such as watering, fertilizing, and treating with certain fungicides.
Types of Fungus
When it comes to fungal infestations, there isn’t one singular answer. There is a range of fungi that can be found on your lawn and can be broken down into two categories; Leaf Disease and Root Disease.
Leaf disease only affects the blade “leaf” of the grass. They aren’t pretty to look at but the silver lining is that if treated properly; it can be back to looking better after a few mowings.
Root Disease affects not only affect the roots of the grass but because the root system is the lifeline of your lawn, it will also affect the grass blades as well. Root diseases also can kill the affected grass leaving you with costly repairs. It is imperative to treat the lawn immediately in order to stop the disease from spreading throughout your lawn.
Signs You May Have A Fungal Problem
While each disease has its own identifying features, the more common ways to identify if you have a turf disease is to notice discoloration, brown spots, dead turf, circular patches, and leaf spots.
As with all fungi, they thrive in warm, humid, and moisture-rich environments. One good way to predict the arrival of a lawn disease is to check for excessive moisture in your lawn.
Identifying a fungal or disease problem is just the beginning. Knowing how to treat it is the other crucial step in creating that perfect lawn.
Identifying Central Indiana’s Five Most Common Lawn Fungus
Knowing what type of lawn fungus you have is crucial for proper treatment and recovery of your lawn.
Red Thread is thin, red, needle-like strands extending from the grass blade. This is a LEAF disease and is caused by a NITROGEN deficiency. The affected areas will recover with the application of nitrogen. The disease can develop at any time of year, but most common in cool conditions, typically in the spring and fall, especially during long evening dew periods.
Dollar Spot form small spots the size of a softball or smaller. This is a LEAF disease and is caused by a NITROGEN deficiency. The patches will typically recover fairly quickly with the application of nitrogen. Dollar Spot typically develops due to excess growth from the constant rain and excess rainfall sets up ideal conditions for Dollar Spot.
Brown Patch appears as large brown spots that are brown all the way through the “patch”. This is a LEAF disease. Brown Patch can develop when temps are in the mid to upper 80’s. High humidity, heavy dew formation, and occasional precipitation also provide ideal growing conditions for this turf disease. Brown Patch can be spread through the lawn from the wheels of the mower. It is typically found around walks and driveways because of the heat that concrete puts off.
Summer patch presents in ring-like patches. This is a ROOT disease and can kill the affected grass. It stays in the soil and can return year after year. This only affects KY Bluegrass. Very dry conditions make this pop. Usually, in the heat of the summer.
A Close look at grass blades infected with leaf spot shows damaged spots or decay on the leaves. From farther away, Leaf spot can resemble drought stress.
Why Do I Have Fungus?
Your lawn is naturally full of fungi spores, some harmless while others can be quite problematic, but the right (or wrong) conditions can cause fungi spores to turn into a harmful turf disease. Each fungus has their own preference when it comes to the condition in which they thrive. However, one thing they all have in common is they all need three components to make conditions right for them to become a problem. This is called the disease triangle. If one component (or side) is missing, then the triangle is not completed, and disease won’t be a problem. These components are:
HOST- the plant must be susceptible to the disease.
PATHOGEN- the disease pathogen must be present
ENVIRONMENTAL- conditions must be favorable for a successful infection
Common Causes of Lawn Fungus
- Humidity and high temperatures
- Improper nutrient balance
- It could even be as simple as cutting your turf too short.
These stresses on your lawn make the grass more susceptible to infection. Take heart, however, because lawn fungi do not have to be a death sentence for your grass. There are steps you can take to treat and prevent fungal growth. The key is to know what you are looking at and take early action.
Once a fungus strikes, the best way to combat it is with a good fungicide. The real trick is to ensure you follow the dosing on the package because too much can do just as much harm as good to your lawn.
Although you cannot control all the above components, some lawn care practices can go a long way toward the prevention of some diseases. This includes:
- Choosing disease-resistant grass such as Turf Type Tall Fescue.
- Mowing frequently at a 3.5 to 4-inch cutting height (removing no more than 1/3 of the grass blade at a time).
- Make sure your lawn gets 1-1.5 inches of water per week and water early in the morning whenever possible (giving time for grass blades to dry during the day).
- Aerate the lawn to allow proper nutrient absorption and break up the thatch (where disease spores can live).
To learn more about common turf disease and how to identify them, check out the Purdue Turfgrass Disease Profiles.
Need help ridding your lawn disease? Let our experts take care of it for you. Check out our Fungicide Program to stop the spread and rid your lawn of turf disease or click here to get a free estimate.