Expect the unexpected

Features - Lawn Care

When it comes to spring turf diseases, unpredictable weather patterns may alter typical fungicide application schedules.

February 13, 2013

It’s no secret that 2012 was no ordinary year. It was the hottest and second-most extreme year on record – ever – in the contiguous United States, according to the National Oceanic and Atmospheric Administration (NOAA).

Punctuated with heat waves, droughts, hurricanes and storm surges, wildfires and floods, the unpredictable weather patterns threw everyone for a loop.

So what does this mean for your spring turf disease outlook? Well, it means it’ll probably keep you guessing.

“The overall theme for 2013 is, ‘Expect the unexpected,’” says Frank Wong, green solutions specialist at Bayer Environmental Science. “Going out on a straight calendar base may go out the window, because things are getting really unpredictable when you’re talking about weather and disease patterns.”

Doug Houseworth, research and development director for Arysta LifeScience turf and ornamental products, puts it more bluntly: “I have never seen disease problems so prevalent in Northern Florida, ever, than I have right now,” he says.

He recently visited with lawn care companies in the Jacksonville area who were having trouble controlling what they thought was large patch with traditional fungicide applications. “What I found is that this year, we are dealing with a completely different pathogen – we’re dealing with take-all. Even I was fooled, and other professionals were fooled,” he says.

It stresses the importance of getting a correct diagnosis, picking the right fungicide and the right rate and the right timing, Houseworth says.

Preparation is key.
Successful LCOs will prepare their team and clients now for the turf diseases coming this spring and summer.

Education is a major component of identifying an issue, and should be your first line of defense.

Recognizing yellow or brown turf as a disease rather than dead or wilted grass could end up saving the lawn – overwatering and overfertilizing could just exacerbate the problem.

“There are some certain indicators that we can be prepared for, and based on the history that we have with that particular location, we can have a pretty good idea of what to expect, assuming normal weather conditions,” says Matt Giese, Syngenta’s technical field manager for the Midwest.

Prepare for that as a minimum, then as weather conditions change, alter your programs, he says.

Once you have an idea what you’re looking for, make sure to keep your eye out early on this year, since conditions are atypical and depending on where you are located, diseases may already be infecting.

Then if you spot something amiss, follow up with a professional diagnosis from a commercial laboratory or university diagnostic lab to ensure that mistakes are minimized and the disease is being treated properly.

There are also several preventative steps you can take to avert diseases. Most fungal diseases need plenty of moisture to thrive, so do what you can to decrease irrigation when possible.

“Even if we do get green up in the winter time (or early spring), the grasses aren’t actively growing,” says Dr. Bruce Martin, professor of plant pathology and physiology at Clemson University. Because the turf doesn’t need much water, cutting back on irrigation may help avoid large patch.

Preventive fungicide applications can also help mitigate disease problems.

Martin recommends two applications in the fall and then a follow-up application in the spring, around green-up, for best results.

Springtime applications are typically more curative because the disease has already infected, but you still may need an application to keep the disease from spreading and the patches from persisting.

In the case of summer patch, which usually occurs in late June, July and August, it’s already almost time to apply preventative treatments.

“You need to treat for it in the late spring in order to prevent it from occurring,” says Kyle Miller, senior technical specialist at BASF. “People with Kentucky Bluegrass lawns need to be aware of that and have fungicide applications go down before those diseases actually occur.”

Keep in mind that effective lawn care requires an integrated approach in addition to these types of applications.

According to Wong, adjusting fertilizer rates, looking at air movement or sunlight penetration should also be factors in your disease prevention.


See how LCOs around the country are saving time and money with pre-emergent programs. Visit www.lawnandlandscape.com and search “pre-emergents.”

Photos courtesy: Large Patch – Bayer; Red Thread – Jim Kerns; Snow Mold – Bayer; Dollar spot – Bayer; Grey Leaf Spot – Bayer


It’s difficult to know exactly what will hit turf come green-up, but there are signs to look for when stepping out this spring. Knowing which conditions cause which diseases will help prepare you and your team, and familiarizing yourself with how to identify these diseases will go a long way in control efforts. “You have the disease triangle – you need a host, you need a pathogen, and you need a conducive environment,” says Jim Kerns, assistant professor and extension specialist of turf grass pathology at North Carolina State University. “The pathogen is always there, the host is always there, so it’s really what the weather is going to bring.”

What you see: Cool, wet weather

What you get: Diseases such as Bipolaris leaf spot, snow mold, or red thread in Rye grass or Kentucky Bluegrass. “If we start to get a lot of wet weather in January, February, March, right about March and April when we start to get green-up, we’ll see the large patch disease, which is caused by Rhizoctonia fungus,” says, Dr. Bruce Martin, professor of plant pathology and physiology at Clemson University.

What to do: Alter irrigation – keep things on the dry side, particularly during the infection periods. DMIs are broad-spectrum sterol inhibitors, which will work on several types of diseases. Look for azoxystrobin or propiconazole as active ingredients.

What you see: Warm, wet conditions

What you get: Large patch, grey leaf spot and dollar spot in Centipede, St. Augustine or Zoyzia grasses.

What to do: There are standard compounds that are used later in the season, such as chlorothalonil, which serves as a protectant fungicide. There are also broad-spectrum fungicides called strobilurins, which work on several different diseases. Look for active ingredients triadimefon, propiconazole, azoxystrobin and fluoxastrobin.

Saving time on tank mixing

One industry supplier is helping LCOs take the guesswork and hassle out of tank mixing.

Holganix provides key clients with a bespoke mixing and filling system for its line of organic fertilizer.

Tom Winkler, CEO of Go Organic Lawn Care in Oakland, N.J., says that prior to installing the system, it took his techs at least 20 minutes to fill a truck. Now it takes eight.

The automated dispensing system known as RAD 600 holds 600 gallons of refrigerated Holganix product. Winkler says trucks are hooked up directly to the system and the operator calculates how many gallons he needs based on his truck size. The original system was designed specifically for Go Organic after Winkler called Holganix and said he needed a better system that could increase truck fill time and also the safety of his crew.

“It’s a cumbersome job to fill a truck with jugs and it presented the opportunity for injury with back problems,” Winkler says. “The company COO put pen to paper and came up with a solution that solves those problems for us. I think the system cost them around $12,000 and they gave it to us on loan. As long as we are using Holganix product, we can use their system – and that’s been amazing. It’s decreased our time at the shop which increases productivity and it makes filling the trucks a safer job.” – Lindsey Getz

Photos courtesy of Holganix