What Kills Johnson Grass But Not Fescue

So, you've got a lawn full of Johnson grass, and you're wondering, "How can I get rid of this stuff without harming my precious fescue?" Well, buckle up, my friend, 'cause we're about to dive into a world of weed warfare, where the good guys wear green, and the bad guys... well, they're just plain annoying.

Johnson Grass: The Unwanted Houseguest

First things first, let's get to know our nemesis. Johnson grass is like that cousin who shows up uninvited, eats all your snacks, and won't leave. It's a warm-season perennial grass, which means it's active when the weather's hot, and it's got a habit of spreading like wildfire. It's tough, it's tenacious, and it's got a root system that's like a real-life Hydra – cut one piece off, and two more grow back!

Now, don't get me wrong, Johnson grass has its uses. It's great for hay, it's drought-tolerant, and it's even used in some biofuel experiments. But in your lawn? Not so much. It's aggressive, it's hard to control, and it can choke out your other grasses, like the lovely fescue you're trying to protect.

Fescue: The Lawn Superhero

Speaking of fescue, let's give it some love. Fescue is a cool-season grass, which means it's at its best when the weather's cool and crisp. It's tough, it's durable, and it's great for high-traffic areas. Plus, it's got a deep root system that helps prevent erosion and keeps your soil healthy. It's like the superhero of your lawn, fighting off weeds and keeping your grass looking lush and green.

But here's the thing, fescue doesn't like to share. It's a bit of a diva, and it wants all the attention. So, when Johnson grass starts muscling in on its territory, fescue needs a helping hand.

Weed Warfare: The Battle Begins

Alright, so you've got Johnson grass invading your lawn, and you want to protect your fescue. The first thing you need to know is that there's no magic bullet. No single solution is going to wipe out Johnson grass without touching your fescue. But don't worry, we've got a few tricks up our sleeves.

Mowing: The First Line of Defense

Believe it or not, mowing can be a powerful weapon in your weed warfare arsenal. Johnson grass grows quickly, and it loves to get tall and lanky. So, keep your lawn mowed short – but not too short. You want to stress out the Johnson grass without damaging your fescue. Aim for a height of about 3 inches for your fescue, and never remove more than one-third of the grass blade at a time.

Here's a fun fact for you: Johnson grass can grow up to 6 inches in a single day! But if you keep it mowed short, it can't reach for the sun, and it'll struggle to grow. It's like giving it a constant trim, so it can't show off its towering height.

Herbicides: The Big Guns

Now, I know what you're thinking. "Herbicides? Isn't that a bit heavy-handed?" Well, yes and no. There are herbicides that can kill Johnson grass without harming fescue, but they're not your average weed killer. They're called selective herbicides, and they target specific weeds while leaving your grass unharmed.

One such herbicide is called clethodim. It's a selective post-emergent herbicide, which means it kills weeds that are already growing, but it leaves your grass untouched. It works by targeting the meristematic cells in the weed's leaves, which are responsible for growth. Without these cells, the weed can't grow, and it eventually dies.

But here's the catch – clethodim only works on young Johnson grass plants. Once the grass gets too tall, the herbicide can't reach the meristematic cells. So, you've got to keep an eye out for new Johnson grass growth and treat it early.

Another option is to use a herbicide that contains the active ingredient sethoxydim. This one works in a similar way to clethodim, but it's a bit more persistent. It can kill Johnson grass that's up to 12 inches tall, giving you a bit more leeway in your treatment schedule.

Soil Health: The Secret Weapon

While mowing and herbicides can help you win the battle against Johnson grass, they're not a long-term solution. The key to keeping your lawn weed-free is to maintain healthy soil. When your soil is healthy, your fescue is strong, and it can outcompete the weeds for resources.

To keep your soil healthy, you need to aerate it, add organic matter, and ensure it's got the right pH balance. You should also make sure your fescue is getting enough water – but not too much. Overwatering can stress out your grass and make it more susceptible to weeds.

Here's a quirky fact for you: Did you know that earthworms can help improve your soil health? They burrow through the soil, creating tiny tunnels that allow air and water to reach the roots of your plants. Plus, they leave behind castings – a fancy word for worm poop – which is rich in nutrients. So, don't be too quick to get rid of those wiggly critters!

Prevention: The Best Cure

As the old saying goes, "An ounce of prevention is worth a pound of cure." The best way to keep Johnson grass out of your lawn is to prevent it from getting in in the first place. Here are a few tips:

• Keep your lawn healthy. A healthy lawn is a dense lawn, and dense lawns don't leave room for weeds.
• Mow regularly. Regular mowing helps to keep weeds at bay and encourages your grass to grow thick and strong.
• Water wisely. Overwatering can stress out your grass and make it more susceptible to weeds. So, make sure you're watering deeply and infrequently.
• Be careful what you plant. Johnson grass can spread through seeds, so be careful when planting new grass or buying new plants. Make sure they're not carrying any unwanted hitchhikers.

And here's a fun fact to leave you with: Did you know that Johnson grass got its name from a man named Henry Johnson? He was a farmer in the early 19th century who brought the grass to the United States from Africa. He thought it would make a great forage crop for his livestock, but he didn't realize that it would become a weed nightmare for lawn owners everywhere!

So, there you have it, folks. The lowdown on how to kill Johnson grass without harming your fescue. It's not easy, and it's not always fun, but with a bit of know-how and a lot of elbow grease, you can keep your lawn looking lush and green, and free from those unwanted weeds.