09/30/2021 Fall Lawn Care #439

Summary: Everyone wants the perfect lawn but using chemical herbicides to maintain your lawn has benefits and risks. Tom Kalb, NDSU Extension horticulturist, joins Sound Ag Advice to fall lawn care and weed control strategies.

Speaker 1: Kelli Anderson, NDSU Ag Communication Specialist
Speaker 2: Tom Kalb, NDSU Extension Horticulturist

Kelli: This is Sound Ag Advice, a weekly feature presented by NDSU Extension. I'm Kelli Anderson, and I'm joined this week by Tom Kalb, the NDSU Extension Horticulturist. Today we're going to be talking about strategies to maintain your lawn, specifically weed control. In a recent Dakota Gardner column, Tom, you talked about balancing the benefits and risks of using herbicides to control weeds. So can you tell us a little bit more about what you mean by balancing the benefits and risks?

Tom: Sure, Kelli. Yeah, everybody wants an attractive weed-free lawn. But on the other hand, nobody wants to be exposed to poisonous chemicals or poisonous herbicides. So, it requires a balanced approach. Now, let's see, the first thing is, we need to have a realistic expectation for our lawn. You know, it's not natural to have a lawn that has no weeds, and it's almost impossible to achieve. And on the other hand, as far as exposing ourselves to poisonous herbicides, we can address this by using herbicides, only when necessary, and when they're most effective. And that gets us to the key point, that is that now right now is the most effective time to kill weeds in your lawns. And the reason why that is, is, as you notice, like, outside, everything's changing the nights are again, longer and cooler. And you know, the dandelions and the thistles they sense that too.
So, you don't see a lot of things growing more leaves now. Instead, they're putting their sugars down into their roots to prepare for winter. And so that's perfect for us. Because how do you kill a dandelion? You've got to get the herbicide down into the roots. And so, if you spray a dandelion now, the dandelion itself will channel the herbicide along with its sugars down into the roots. And so that's how we get our most effective kill. Well, now is the most effective time and you can have a very good quality lawn if you spray only one time a year, but you do it at the most effective time, which is right now.

Kelli: So Tom, if a homeowner does decide to use herbicides right now, what are some of the strategies they might use for applying those?

Tom: Choose the right herbicide to begin with. And in most cases, we're going after broadleaf weeds and chemicals that most people use know are what we call a trimec formulation. Try means three, it's got three ingredients. And it's like 2:4-D, MCPP and dicamba, so look for an effective chemical, and then follow the label carefully. Mix it at the proper rate. Don't overdo it. Otherwise, you can harm your landscape plants with the excessive rate. Also, spray in a way that's safe for you, wear protective clothing. Don't go outside with sandals and shorts on. Respect the chemicals. They're poisonous. So, wear like a long sleeve shirt, long trousers. Were some non-absorbent gloves, non-absorbent shoes, and spray when there's a minimal risk of drift. So, you want to spray when the winds are calm.
You want to use a heavy droplet not a fine mist that can drift easily. And then also avoid a really high temperatures like when it gets into the high 80s. Unfortunately, there's not too many of those days left, so we don't worry so much about that right now. Follow the label instructions. And also, as far as safety, stay off the lawn, at least until the chemical dries. And if you can stay off 24 hours that's even better for you and your pets to limit your exposure. Another thing Kelli, is that you don't have to spray your entire lawn, maybe just do some spot spraying of the worst areas, the most weedy areas. Again, that will minimize the exposure of you and your landscape plants to these harmful pesticides.

Kelli: And finally, Tom, if you choose not to use a herbicide, what are some other ways that you can maintain a healthy lawn without those chemicals?

Tom: That's a good question. So like we're talking about a more holistic approach to lawn care. And so there's something to do. One is cut your lawn tall, the taller the better.
Let the grass clippings fall. Also fertilize your lawn. Because all these tests what they will do is you're going to get a thicker turf and a thick turf. A thick, tall turf can smother out those weed seedlings before they get established.

Kelli: If people have questions about fall lawn care, where can they go for more information?

Tom: We're very lucky to have a great team of county agents that can provide the information that you need, so just contact your local NDSU county Extension agent.

Kelli: All right. Thank you for your time today, Tom. Our guest today has been Tom Kalb, NDSU Extension Horticulturist. This has been Sound Ag Advice, a weekly feature presented by NDSU Extension.

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