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From east to west and everywhere in between, diseases will pop up in your customers’ lawns. While some can be prevented or treated with products, others can be handled with proper watering or mowing practices. We spoke to LCOs to find out how they approach disease control in the winter and spring months.


In southern New Hampshire, Brian Labrie works hand-in-hand with the subcontractors who make chemical applications for his company, B.H. Labrie Landscape Co. For him, red thread and pink snow mold are the two main culprits in the winter and on into the spring.

New Hampshire has been dealing with drought conditions for nearly a year, so red thread, which thrives in wet conditions, hasn’t been much of an issue. “Typically, that exists when it’s really wet and damp and we don’t get a lot of sunlight,” Labrie says. “So what we try to do to combat the red thread is make sure that yards are cleaned up and leaves are cleaned off in the fall in order to get any tiny little bit of sunlight you can get into those grass roots.”

“A little bit of nitro boost like that – it fattens up the roots a little bit and I just think it makes for a healthier lawn going into the cold season where everything becomes dormant.” – Brian Labrie, B.H. Labrie Landscape Co.

But pink snow mold, which pops up under snow banks and other snowpack, was an issue last spring. Crews chase the disease all the way into May, Labrie says.

To combat diseases, B.H. Labrie Landscape Co. treats lawns with a lime application in the fall, along with a winterizer fertilizer in late September and early October.

“A little bit of a nitro boost like that – it fattens up the roots a little bit and I just think it makes for a healthier lawn going into the cold season where everything becomes dormant,” Labrie says.

Some turf in Northern Colorado went dormant by late November so LCOs didn’t have many concerns with diseases like pythium blight.
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When problems pop up and customers call to complain, Labrie uses face time and education to keep his customers happy. If a property manager or resident calls, someone from the team will meet with the customer and explain the situation. Since grass seed doesn’t germinate until the weather hits around 55 degrees, there isn’t much to do until the weather warms up.

“You hit them with a little bit of education and a handshake and a plan of action, and just make sure that when you leave, they understand that it’s going to take time to get some of these things resolved,” he says. – Kate Spirgen


Eric Brown, director of agronomy at Orlando-based Massey Services, says large patch is the main threat in the Florida market every winter. When weather gets damp and evening temperatures drop, conditions are right for the fungus to spread, especially in St. Augustine grass lawns.

“It could turn into an active season, but it hasn’t been a bad season for large patch,” Brown says. “But every year it is out there.”

Large patch is soil-borne, so once it’s in a lawn, it is difficult to eradicate. Adam Jones, Massey’s vice president for quality assurance, says technicians know which lawns tend to get large patch every year, and treatments are built into customers’ lawn care programs.

“As soon as we start seeing it, we start treating for it and start communicating,” Jones says.

Massey begins preventative fungicide applications in September and repeats them every 30 days, but the company recommends cultural changes first: ensuring the proper variety of turf for the location, keeping grass at the proper height and not overwatering. Excessive moisture helps the fungus grow and turf that’s too short is stressed, making it even more susceptible to the disease.

Further north in Georgia, a drought this fall has been a boon to technicians at TurfPride Lawncare in Kennesaw, Georgia – at least on warm-season grass.

Zach Coward, operations manager at the $5-million company, says the lack of water has prevented many weeds from gaining as much ground in zoysia and Bermuda grass lawns as they would in a rainy fall.

“The drought has helped with weed coverage,” Coward says. “It has given us a little time to put down pre-emergents to keep them from germinating. (But) the drought is absolutely killing our fescue lawns.”

The company wraps up most of its fungicide applications by September, Coward says. In the fall and winter, Turf Pride applies broadleaf weed control and pre-emergent treatments. It does another round for early spring weeds in January and February.

Dick Bare at Arbornomics in the Atlanta market says brown patch in zoysia and fescue lawns is a common winter problem that can be difficult to identify because the turf goes dormant.

In the spring, homeowners are left with ugly brown patches, which his technicians treat for an extra charge. It isn’t included in the standard lawn care program.

“We treat in the winter if we can tell it’s there,” Bare says. “They’re a real problem. They can be very stubborn.” – Chuck Bowen


In states like Indiana, Missouri, Illinois and Iowa, winter diseases aren’t very high on an LCO’s radar.

“It’s probably one of the last things I’d expect to talk about,” says Jeff Smith, service manager at Lawn Cure of Southern Indiana.

In his 36 years with the company, he’s seen about five lawns with winter diseases.

“And in those situations, it may have been when we had snow coverage that took longer to melt,” he says.

Harold Enger, director of education at Spring-Green Lawn Care, agrees. “It’s a non-issue basically because it’s winter time,” he says.

Smith says the lack of winter disease is because the grass in Indiana, typically Bermuda and zoysia, goes dormant during that time.

“As a general rule, most grasses that show disease problems will be when they’re actively growing, not dormant,” he says. “When these grasses turn straw brown for the winter, they’re that way for six months.”

In Illinois, Enger says the lawns stay green, except for the yards with zoysia, but the turf is hardened up, so it doesn’t see much activity.

Both agree a colder winter is better for the lawn. “Cool season grasses can handle cold weather even if we don’t have snow,” Enger says.

“Snow is a good thing, it will insulate the grass underneath, but I’ve seen winters where we haven’t seen a lot of snow. The grass can dry out in the winter time … but turf is a remarkable plant, so it will recover.”

If snow mold is not treated, the mold will dry out and glue the grass blades together, making it harder for new growth to pass that barrier.
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Instead of spending time prepping for winter diseases, LCOs are beginning spring preparation, something Enger says will go into full swing in February or March.

But now, he’s asking homeowners to keep lawns mowed so the grass isn’t too long when the snow does fall.

“As that snow falls, it pushes the grass down and the snow mold will develop better,” he says. He also tells homeowners to rake up leaves, or mulch them on top of the grass, but not to leave them as cover.

He says snow mold, both grey and pink, is a problem he’s seen in the spring, but there’s not much treatment involved on his end.

“You take a rake, or your fingers, go through the snow mold, break it up and everything’s done,” he says.

If left, the mold will dry out and glue the grass blades together, making it harder for new growth to pass that barrier. Raking to break up the mold will prevent that.

LCOs may also see red thread or leaf spot if the early spring is wet, or rust if the spring is very dry. However, Enger says the best prevention is good lawn care practices.

“Mowing high, watering as needed, proper fertilization, thatch control, core aeration, overseeding on a regular basis … those are all things that are going to help you maintain a healthy lawn,” Enger says. – Katie Tuttle


In northern Colorado, the weather varies so much that it makes it hard to plan, says Brian Pabst, operations manager at American Turf & Tree Care in Greeley, Colorado.

As for the winter of 2015-16, much of the turf in his area went dormant by late November, so he doesn’t have many concerns about snow mold or pythium blight.

But if clients do request some winter service, Pabst offers a couple of different organic treatments to help with disease control. One being elemental sulfur, which Pabst says is a necessity to help buffer the massive amounts of salt in the top soil, especially in Kentucky bluegrass lawns.

“Our average soil pH in this area is from 7.2-8.5,” he says. “We are using sulfur to acidify the soil and to help stimulate and elevate plant enzyme levels to keep the plant as healthy as it can be.”

Pabst says the elemental sulfur also helps to mitigate another major issue in Kentucky bluegrass – necrotic ring spot. “It’s amazing what one to two applications at a heavy rate of sulfur will do,” he says.

American Turf also uses liquid humic acid applications in its lawn care spray program because Pabst likes the rapid availability and response from the plant, and a granular 71 percent humic acid application.

“I personally use two heavy rate applications at my own property in spring and mid-fall, and over the years have had great luck with disease recovery and adding tilth to the soil,” he says.

Next door to Pabst in northern Utah, David Moore, president of Ferta-Lawn, says he also sees a lot of necrotic ring spot. He says he’ll apply fungicides when the soil reaches 61 degrees, which is usually in mid-May in his area, and then he applies another application 30 days later.

Moore, who starts spring applications in the second week of March, says it’s a difficult disease to treat, and two years ago, changed his company’s fertilizer program to control the disease.

“We lower the urea we use or the quick-release forms and go more into a slow-release blend,” he says.

“We now use a slow-release blend of fertilizer which feeds the grass at slower rates. Instead of getting a quick response, we want the plant to feed at slower rates which can take 21-plus days to fully get into the plant system. Depending on what rate of slow release product will depend on how long it lasts also.”

Moore says overseeding with a grass that is resistant to the disease can get rid of the problem, but may not work aesthetically.

“The problem is that most will try a ryegrass and it will look different than your bluegrass, but there are bluegrasses that are resistant to it,” he says. Moore says the wetter it is in the spring, the worse necrotic ring spot can get.

Moore usually doesn’t treat other diseases he sees, or does so sparingly. Snow mold will fix itself with aeration and a little warm weather. LCOs in his area will also see the occasional leaf spot and ascochyta leaf blight in mid to late May, but that is hit and miss and he often does not treat it.

“(We) just treat it at that point if it is severe enough with a fungicide that is a contact spray,” he says, adding that myclobutanil works for him. – Brian Horn