COMMENTARY

Rust is a lawn pest too

Disease on the blades of grass is caused by a fungus

8/20/2013
BY KELLY HEIDBREDER
IN THE GARDEN
Kelly Heidbreder
Kelly Heidbreder

My dad is one of those people who is really fussy about his lawn. His grass is always mowed at the perfect height, he has it nourished and treated by a professional four times a year and since he is a huge Tigers fan, he likes to have it mowed so it looks like the outfield at Comerica Park.

OK, I might be exaggerating about that last one, but he is truly a turf tyrant. His lawn has looked beautiful for years because he pays attention to the details. And there’s one detail he’d really like to get rid of: rust.

Rusty lawn

Rust disease on the blades of grass is caused by a fungus and other problems with your turf. Some lawn experts say it is because your lawn needs a boost of nitrogen. Rust will grow when your lawn is under stress. That means it has gotten too dry, cut too short, or is hungry, it is vulnerable to fungus.

It usually forms around mid-summer through late fall. According to Ohio State University, “Grasses with a fine texture and deep color, like perennial ryegrass and Kentucky bluegrass, are the most susceptible.”

Frequent light showers can also be tough on your lawn because the roots will stay at the surface rather than reaching deep for moisture.

Grass rust.
Grass rust.

Take a close look

If you take a magnifying glass and look closely at the blades of grass, you will see orange or yellow-orange bumps on the surface. Those are the spores. When you walk through the grass, those spores are disturbed and they spread to your shoes, mower and anything else they can cling to. And each time you walk through it, you are spreading it around to other parts of your lawn.

Ohio State University scientists say rust may weaken turf grasses and make them more susceptible to other problems. Over time, it can weaken your lawn, so you don’t want to ignore it.

The best way to avoid getting rust is to plant rust resistant grasses. But if your lawn is well established, you need to keep it healthy throughout the year and try to avoid over watering. Always water your lawn early in the day so the moisture on the blades has time to dry off before bacteria can grow.

Even though it is a fungus, professional turf managers say fungicides are rarely suggested. Keep the grass healthy first. Mow it often to remove the spores, preventing them from spreading. Keep air flowing around your turf and make sure it isn’t too shady. Pump up the nitrogen in the fall so your turf has a chance to grow out of the rust. Mow it a little shorter in September when it is really growing strong to cut the affected tips of the blades off and cut it frequently to make sure you get it all.

Contact Kelly Heidbreder at getgrowing@gmail.com