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Episode 3

Pre-Emergent Crabgrass Control

On this special episode of the Around the Turf Scene Podcast, Justin Stewart and Dave Hillger join Beth Berry to discuss crabgrass prevention. Justin and Dave talk about using Dimension for pre-emergent and early post-emergent crabgrass control. Dimension contains the active ingredient dithiopyr. Listen to learn what makes Dimension unique, including how it compares to prodiamine products. This podcast was originally recorded for Turf’s Up Radio and repurposed for the Around the Turf Scene podcast.

About our guests:
Justin Stewart holds master of science degrees in plant pathology and industrial administration, in addition to a bachelor of science degree in agronomy, all from Purdue University. He worked as a golf course superintendent before transitioning to sales in 2007. Since 2016, Justin has worked for Corteva AgriScience, where he is currently the Eastern sales leader.

Dave Hillger is a field scientist for Corteva AgriScience. He began his career as a teacher after earning an agricultural education degree from Ohio State University. He later studied botany and plant pathology at Purdue University, transitioning his career to research. Dave was a researcher in crop science and pasture management before his current position at Corteva.

About our host:
Beth Berry is the vice president of turf and ornamental sales at Advanced Turf Solutions. Previously, she was the vice president of growth and alliance for Real Green software, where she managed enterprise accounts and strategic partnerships for the green industry software company. Prior to Real Green, Beth was the director of customer service for Scotts Miracle-Gro. She currently hosts the show “Ahead of the Curb” on Turf’s Up Radio.

Beth Berry 00:10
Oh my gosh, am I excited today! Today is crabgrass preventative day with my buddies from Corteva. Justin, just know that all of the technical issues are on my end, okay? It’s not you. It’s always me here. Thank you so much for joining us today. This is the first time we have recorded on Zoom along with Audio Hijack. So we’re live on Turf’s Up Radio. Your industry. Your station. I’m Beth Berry, I’m Ahead of the Curb, and I am the vice president of turf and ornamental for Advanced Turf Solutions. We are based in Fishers, Indiana and I have had so much fun this year catching up with old friends in the industry, from when I was at Scotts and when I was at Real Green, and partnering with really cool folks like yourself and the Corteva team. Tell us about the features of Dimension that will take away my PTSD from when I was at Scotts Miracle Grow, and we would have the yellow dog. And also, “Oh, I wasn’t home today to water that.” So what are some of the features that really make Dimension a cool product?

Justin Stewart 01:19
Yeah, so hopefully you can hear me all right.

Beth Berry 01:25
I can hear you loud and clear.

Justin Stewart 01:28
Perfect, awesome. So yeah, Dave kind of touched on a lot of those, but he touched a little bit on the ability for it to, you know, not have any staining just due to the pyridine chemistry versus the DNA chemistry. He touched on the post-emergent crabgrass control. So if they missed that window, I think the biggest thing is just the flexibility of Dimension. Being able to weatherproof, you know, really not have to be worried about whether or not we missed that window, not worried about whether or not we got the frost, or was the frost enough to delay germination. You know, just having that peace of mind is huge. And having that foundation of having that pre-emergent down and knowing that it’s going to be there and be able to to work regardless of what the weather throws at you is a huge, huge deal. So I guess that’s the biggest thing.

Beth Berry 02:21
Here in the Midwest, it’s 70 degrees. I’m loving this. And so if we get a few days here, you’re saying the crabgrass is going to start germinating.

Justin Stewart 02:33
Potentially, it could. Yeah, we have enough of those degree days, it absolutely could. And Dave, I know there’s some studies out there. I know, I’ve looked at a few from, you know, just even down in Georgia. There’s a couple at UGA, there’s Arkansas, some at Rutgers, that have all shown that post-emergent control guys can feel comfortable about the fact that if it is germinating, they can get some pretty good control up to that first tiller stage.

Dave Hillger 03:03
Yeah, that’s right. I mean, it’s a temperature thing, so having those air temperatures would drive the soil temperatures up.

Beth Berry 03:13
And so you’ve got a longer window, but my favorite part (before I get to Aaron Bucci’s questions here) is, how about the fact that it has post-emergent qualities as well?

Dave Hillger 03:30
Well yeah, that’s definitely one of our our main features of the dithiopyr Dimension product is that it brings that post-emergence control. And that’s not just post from a liquid application. That’s also from a granular application, so our applicators don’t have to switch gears and go from a dry to a liquid in order to get that post control. They can keep using that dry material on that fertilizer and still get that control that they’re looking for.

Beth Berry 04:00
That is amazing. Up to five tillers, am I correct?

Dave Hillger 04:03
That is five tillers. We generally talk about that for warmer-season grasses. In the North, we would probably say, you know, that three tiller area probably is where you’re going to see the most just because of the competition differences that we would see in the North. But still, yeah, well past that early emergence, but quite into that tillering stage.

Beth Berry 04:27
Let’s talk about rates compared to prodiamine. What should our listeners know about the rates of Dimension versus prodiamine?

Dave Hillger 04:37
Yeah, typically we see—and it’s a great question because we oftentimes get asked that because I know with prodiamine there’s a lot of confusion when you start to look at some of the brands, right, and start to see the the 2EW versus the 4L in terms of prodiamine and so folks are like, “Oh, I’m using one pint of each, so it must be the same.” Well, it’s not. You got to look at the loading, right? So we typically see a lot of differences there. And we have to kind of remind folks that the loading’s not the same. And so typically, you see if you’re using, you know, prodiamine at a certain rate, you’re going to use about half of that rate in Dimension. So if you’re using a full pound of AI of prodiamine, you’re probably going to need around that half-pound rate of active for Dimension. And so usually when we’re using Dimension, it’s about that one and a half to two times that for prodiamine. So you’re using much less than what you would in terms of active ingredients when it comes to Dimension, if that makes sense.

Beth Berry 05:48
It does make sense. Let’s talk about the formulation flexibility. I’m a big proponent of taking the entire T&O world back to 100% liquid. I started at ChemLawn with the big tankers. I don’t see freight going anywhere, and so I’m a big proponent of liquid. I think consumers view it as a professional grade application that they can’t get at Home Depot, but that’s a debate for another day. You all have a lot of flexibility in terms of how this is formulated. Tell us about it.

Dave Hillger 06:21
Go ahead, Justin.

Justin Stewart 06:24
It’s a lot of options, right? You’ve got a lot of options. We’ve got everything from a liquid standpoint, we’ve got the water-based formulation in the EW. You’re looking at half gallons to two and a half gallons to 30-gallon drums. You’ve got, for folks that love to have that, you know, you’ve got those folks that really liked those water-soluble packets that are out there. We’ve got the 40 WSP option. You’ve also got it on a granule fertilizer. I mean, that’s a huge win for a lot of folks that like to spread it. So definitely a lot of options out there for that. We also have co-packs that are packaged with our other product called Defendor. That’s more of a broad-leaf product that works great for that cool-season application that goes down along with Dimension. And so it’s just a lot of opportunities for flexibility there for whatever they’re looking for when it comes to applying that pre-emergent to get that foundational, you know, application down.

Beth Berry 07:26
Defendor is amazing, I would just like to say.

Dave Hillger 07:31
It’s been a good one, for sure.

Beth Berry 07:33
So tell us about the chemistry, the pyridine chemistry versus DNA.

Justin Stewart 07:40
So they’re both kind of in that same category. They’re called biotic disruptors. So they work on the roots and really tender shoots that are underground. Now the DNAs work in a slightly different way, a different site of action, if you will, than what we see with the dithiopyr and the Dimension product. In essence, they work in that they prevent that root from properly growing and dividing and spreading and everything that roots need to do underneath the ground. And they break that process up inside the plant. So they work a lot the same way. It’s just what specific site within that process they act upon.

Beth Berry 08:31
I should have spent more time in science class, I can tell you that. So what is it specifically that allows it to be non-staining, which, by the way, really saves T&O owners a lot of call backs?

Justin Stewart 08:44
That comes right back from the formulation. The active ingredient itself is not formulated with that yellow-type color. And, you know, if we could take the yellow out of the DNA products, they probably would’ve by now. It’s just that’s the nature of that particular molecule in how it’s formulated and its active ingredients.

Dave Hillger 09:07
And there’s some other characteristics too that I think are unique to the pyridine chemistries. I mean, as you look at things that, you know, when you look at dithiopyr versus prodiamine, some of the things that are different, we talked about the watering in, right, that 24 to 48 hours of having to get watered in. The DNAs typically break down by sunlight. So they have to get watered in in order to get away from that sunlight, right? The half-life is usually two to three days, whereas the pyridines typically don’t break down by sunlight, usually microbial action. So they they have a little bit longer that they can sit out without being watered in and so things like that kind of differentiate them within that group.

Beth Berry 09:51
Interesting. Okay, we’re going to talk about driver weeds before we hear from our sponsors again. Give me all the goods on the driver weeds.

Justin Stewart 10:02
Dimension’s got some great things on the label. Obviously, along with, you know, some of the things that you’ll see on prodiamine’s label as well, obviously crabgrass, goosegrass, those types of things. Dimension’s also going to pick up some things like bittercress. It’s going to pick up things like dallisgrass, stiltgrass, black medic, lespedeza, some things that you’re not going to see on some of those other pre-emergent labels. And so those key weeds that you see across some of the Midwest into the Northeast, Mid-South areas, even in the Southeast, are pretty key and have been some reasons why folks have been choosing Dimension for a long time.

Beth Berry 10:49
Wow. How long has Dimension been around?

Dave Hillger 10:53
Oh, 80s? Yeah, probably late 80s, early 90s.

Beth Berry 11:05
And is this true? It’s a one-app across most zones?

Justin Stewart 11:11
Well, you certainly could go the one app. We actually recommend a split application.

Beth Berry 11:15

Justin Stewart 11:16
Just simply to keep, well, knowing that Dimension has that early post activity as well. We see it better as a split application, that first one going out, you know, in the spring time to get a residual product pre-emerge, but then kind of to recharge, if you will, that residual component, but also pick up any ones that may have escaped through with that second application. Really, we find the most consistent and best results with a split application of this product.

Beth Berry 11:49
When I was at Scotts Lawn Service, we—in conjunction with Ernst and Young—did a huge project on service called “Callbacks and Cancel: Save Retention Rates,” and when you would thin-slice service calls for the reason of crabgrass. Gosh, those were really tough to solve. And if the customer, either because of weather demands, or the customer was on financial hold, or for whatever reason we didn’t get that down in that very tight window, you weren’t going to control it very well with post-emergents the rest of the year. And we didn’t get those customers back. It is such a critical aspect of turf and ornamental that ties directly to retention. So when I have conversations with turf and ornamental owners looking for a bargain route to pre-emergent, it’s just dangerous territory because if you don’t control that in the window where it is controllable, you’re not going to win that customer back. They already don’t trust you. And there is such amazing science with these premium pre-emergents available.

Dave Hillger 12:58

Justin Stewart 12:59
That’s a great point.

Beth Berry 13:01
What about fall applications? And I’m just talking way over my head now. Is anyone using it in the fall or winter in some areas?

Justin Stewart 13:13
Yeah, we actually see it quite a bit used in the fall actually for Poa control. They’ll use it a lot in the Southeast, Mid-South areas for Poa applications. And a lot of times in the South they’ll actually use a combination with a one of our product called Kerb, another pre-emergent that has some post-emergent capabilities as well for Poa. So it makes a good rotation-in product with that as well as a few other pre-emergents they’ll work in and post-emergents, depending on what they’re trying to do with the transition with ryegrass if they are overseeding during the winter months.

Beth Berry 13:50
Interesting. Any turf types that Dimension is not labeled for?

Dave Hillger 13:57
Just some of your colonial bentgrass, you may see a little bit of injury. But it’s probably one of the safest product we see in pre-emergents on turfgrass. It’s everything from really tender St. Augustine up to, you know, fescue and Bermudagrass that you can beat on and not have any issues with.

Beth Berry 14:17
Very, very versatile. I like the way you said “beat on.”

Dave Hillger 14:21
Well, we certainly do beat on our fescue and Bermudagrass athletic fields, for sure.

Beth Berry 14:27
So ATS obviously serves turf and ornamental (those are my people), golf, and sports turf. So they perform equally on all those type turfs?

Dave Hillger 14:40
They do, yeah, it certainly does. You know, we look at it from a golf standpoint, you know, the heights that they use, the intensive management that they have. All the way up to your, you know, industrial parks that have very low management programs on their turf, you see excellent performance from this product.

Beth Berry 15:00
I’ve learned more about fungicides for golf courses in the last 90 days than I’ve known in three decades being at ATS. But Justin, you are a former superintendent. Do you approach crabgrass control any differently on a golf course than you would in turf and ornamental?

Justin Stewart 15:20
Yeah, I think it’s kind of the same in a way. I mean, you’re using it as kind of a backbone, I guess, or as a foundation. It’s something that you just don’t skimp. You don’t skip. It doesn’t matter what your budget is, you put it in. It’s one of those things where you have to have it. And the year that you skip it, if you do, you know it. And it’s going to be a battle fighting it. Just like you would with fungicides, right? You skimp on your fungicides, and you’re going to know it. And it’s going to be a battle trying to get back into it. So I think it’s one of those things where on the golf course, we just put it in, we did double shots, we did split applications, and we did it every year, religiously. And it was just something that we knew we had to have.

Beth Berry 16:16
What’s the science say about skipping a year? Can you get away with that if you’ve got a good stand of turf?

Dave Hillger 16:24
It’s not a complete reset. But it’s pretty close.

Justin Stewart 16:27
You know, that one seed rain or seed generation that year you skip, it’ll take two to three years to battle that back, unfortunately, just because crabgrass is a very proficient seed producer, and that seed will stay viable for a few years underneath that thatch. So yeah, you miss a year, you’re pegging it forward for the next two or three.

Beth Berry 16:55
Okay, we’re going take a last break here from our sponsors. And when we come back, we’re going to talk about all the asterisks, like, “What about when I’m seeding, Beth? When can I apply that? What if it rains right after that application?” All of those FAQs that we would get from residential homeowners that have to do with pre-emergent crabgrass control. We will be right back after a word from our sponsors. I’m Beth Berry, Ahead of the Curb. Your industry. Your station. Here on Turf’s Up.

Sponsor: Steel Green Manufacturing 17:27
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Beth Berry 18:01
I am back. This is Beth Berry. I am your host of Ahead of the Curb on Turf’s Up Radio. Your industry. Your station. And I actually have two guests from Corteva with me today, talking about all things pre-emergent crabgrass control. We’re all based in Indianapolis. We should have just hung out on someone’s patio. It’s going to be like a blockbuster germination day today. It’s that kind of day, usually we don’t see till May, that makes me want to play hooky here in Indiana. I’m getting ready to head to Florida, so I’ll get more of this, hopefully, when I get there.

Beth Berry 18:35
But let’s talk about the industry first and then we’re going to finish up our hour with some of the asterisks and some of the FAQs I get from Turf’s Up Radio listeners and Advanced Turf clients about your product, which is completely amazing. The demand so far has been fantastic again. In March of 2020 when I was at Real Green, we were battening down the hatches, and some states weren’t essential, and I led the charge with some of my friends at NALP to help get us essential in every single state. And then we still weren’t sure, you know, is demand going to still be there for turf and ornamental? I was in the industry in 2008, and those were some scary days, my friend. And you don’t have to look much farther than your local cable TV station to wonder, “Oh gosh, is this going to continue?” I had a conversation with Alex Cannon last night, our founder and he—if you know Alex, he’s pretty reserved anyway—but he’s like, “Well, it looks like it’s going to be another good year,” as he’s knocking on wood. I suppose you all are seeing what the rest of our listeners are seeing, which is demand is still very high for residential and commercial turf and ornamental treatment.

Justin Stewart 19:54
Absolutely. Yeah, we’re seeing, I mean, it’s been amazing. I mean, you seee golf course rounds are up significantly and continue to be a lot of interest in golf, which is fantastic for the industry, quite frankly. Lawn care operators seem to be adding accounts left and right, which has been great. The nursery business, we have reports of nurseries being out of stock of their inventories just because they can’t keep stuff in. And so it’s definitely a good problem to have. Folks are focusing their money and dollars on their houses and on golf memberships, things like that. So it’s been a great problem to have in terms of leading to stock out the products and things like that. So it’s been good, but bad at the same time, but a lot of demand. And I don’t think we’re going to see an end to that here anytime soon. You know, at least not in 2022, based on all indicators right now.

Beth Berry 20:56
And that’s what we’re seeing, and that’s very exciting. And now for the ten million dollar question. What about availability like, “Beth, you’ve got us so hyped up. We’re all ready to go out and buy Dimension. So help me if I call ATS and can’t get it. There’s going to be trouble.”

Justin Stewart 21:13
Yeah, we’re constantly battling to try to get production. So yeah, we’ve got production online. Actually, I think if I’m not mistaken, I believe, I just talked to our marketing manager here recently, and I think we’re actually producing right now.

Dave Hillger 21:31
Yeah, this week.

Justin Stewart 21:32
So it’s very timely that we’re having this conversation.

Beth Berry 21:37
And just so you guys know, I checked with Christina in purchasing before I asked that question, and she received the same indication from you all before I walked you into a corner.

Justin Stewart 21:48
Good, good, good. So yeah, we have production going. Usually with, especially with Dimension, it’s usually all year round, or at least most of the year we’re producing. So it’s definitely something that we always have going.

Beth Berry 22:02
That’s amazing. Okay, so FAQs, frequently asked questions, from turf and ornamental business owners and managers. “Beth, where does Dimension fit in with a customer that I need to do some seeding with?” What is your best advice for that?

Dave Hillger 22:23
I would say that for Dimension, if you look at this, your seeding probably going to hopefully target that fall seeding timing. So spring application, you should be fine. You certainly don’t want to push it too far into the summer, because Dimension would cause some issues with receding grasses in particular, into an overseeding or even a redo of a sod area. So you do have to be careful of that just to avoid any challenges when it comes to that seed germination.

Beth Berry 23:00
I’ve learned more about seed than I’ve known in three decades from Rusty Stachlewitz. We are a powerhouse of seed at Advanced Turf. And he states, you know, for most areas, certainly fall is still the best time to seed. It goes hand in hand with aeration. But you certainly should not see if you’re using Dimension—is that correct?

Justin Stewart 23:24
Yes, that later application, certainly not in fall. You can’t seed right after an application, for sure.

Beth Berry 23:31
And what’s the tolerance for rainfall? Going back to my PTSD days at Scotts when the customer would call in and say, “It literally monsooned right after he left.” So sometimes that would be true. And, you know, in the Midwest, you can’t predict the weather. If we didn’t go treat lawns every time there was a 30% chance of rain, we’d never get anything done. But sometimes it would rain right afterwards. And sometimes it would be a day later and you’d still have to convince the customer. What’s the tolerance for irrigated turf following an application of Dimension?

Dave Hillger 24:09
We’re talking about pre-emergence. So, you know, we talked about this earlier, about irrigating or watering in. So, you know, a typical rainstorm after an application is probably a good thing in this case because you’re getting it into that soil where that seed’s at. Now if we’re talking post-emergent control, we like to see, you know, a few hours, you know, a day, if we can, applied onto that plant before it would be watered or washed through. So, you know, from a pre-emergence I think we’re set. You know, gullywashers, you know, where you get three inches of rain, that might be a little bit different story, but obviously, we can’t ever predict those. But, you know, just a simple rainstorm afterwards, we’re fine.

Beth Berry 24:52
And if it were a gullywasher, as we get here in the Midwest—and that is actually the technical term for it. I know you guys went to Purdue and I went to IU, but gully washer is the term. How soon could you reapply that in order to make that homeowner happy that you did the reapplication?

Dave Hillger 25:13
Well, a lot of that I think you probably want to wait and see. You don’t want to go out just assuming that it’s all going to be gone. So, you know, give it a week, a couple weeks to see if you see the control or germinating grasses. But generally speaking, when we talk about reapplications or sequential applications, we’re going to wait at least five weeks between those to really make sure what we did the first time worked, or, you know, unfortunately, sometimes it doesn’t work in rare conditions like this. So just give the product time, whether it be, you know, Dimension that we’re talking about now, or even other products. It’s just a good idea not to panic, the day after, say, “Well, it must be gone because it rained.”

Beth Berry 25:58

Dave Hillger 25:59
That’s probably not the right answer to have.

Justin Stewart 26:02
Yeah, these products are not ones that typically will move through the soil very easily. So once they bind, they’re pretty insoluble. So they’re only going to move with the soil if the soil moves.

Beth Berry 26:14
And that’s been the story for as long as I’ve been in the industry. It’s just so difficult to convince the homeowner who thinks it’s all gone and I need to reapply. Those are the same people who think more is better and use Roundup on their lawn. “I’m going to get rid of that dandelion. I just went and bought some Roundup.” You go. Let’s watch that. So last few minutes we have here, back on the post-emergent qualities of the product. What is the timeframe for which you would advise consumers that they would start to see the weeds curl and die? How long does it take for the post-emergent to begin to work?

Justin Stewart 26:52
The injury symptoms in the control is going to be slow as well, because it just it’s a biology effect. So it takes a while for, quite honestly, the injury to grow into the plant, if you want to think of it that way. Now, you know, things are growing nice, got enough moisture, enough sunlight, and all that. Temperatures are nice. You’ll probably see effects within a few days to a week, for sure. I know, in previous years where I’ve actually, “played around” with it in my backyard for research, I’ve actually seen excellent performance within three, four days. You see those crabgrasses starting to turn a little brown or purple color and start to die. One of the first things that I noticed with those is really that they stopped growing. You know, if you mowed them and they’re three inches tall, a week later, they’re still three inches tall. So you know, they immediately stop that activity. That’s probably going to be the first thing you see.

Beth Berry 27:50
Interesting. Very, very interesting. You know, what we’re going to talk about in a couple weeks, I don’t know if it’s you all, but we’re going to talk about a very cool product called Crew. Anyone want to give me a little commercial for Crew?

Justin Stewart 28:07
It’s a great product. Crew is a great product. So it actually has a little bit of Dimension in there along with another one of our pre-emergents and Gallery. So isoxaben, another great pre-emergent for broadleaf control.

Beth Berry 28:21
It’s going to be exciting. It’s going to be a very cool year, that’s for sure. And then the product that’s not labeled (darn it) for residential is GameOn. What a great, great brand name for you all. Give us a little 60-second pitch on GameOn.

Dave Hillger 28:37
GameOn is probably going to be the premier product that you see used. The flexibility of it, you know, it currently is not residential, but we’re actually very hopeful that that’ll be changing in the very near future. We see this as, you know, it gives you your typical broadleaf control that you’re looking for, your clover, your dandelion, what am I forgetting? Clover, dandelion. . .

Justin Stewart 29:06

Justin Stewart 29:07
Plantain. You know, some of your typical weeds, but it also picks up some of your other tougher ones. It’ll pick up ground ivy. It’ll pick up some of your, actually, it’ll pick up violet with multiple applications, you know, so, you know, tougher weeds that we see later in the fall. And it has that flexibility to be applied earlier in the spring through the summer. As we see restrictions with 24D products due to temperatures, our product, the GameOn product does not have that temperature restriction. So you have that flexibility as well.

Beth Berry 29:44
That is going to be absolutely amazing. You guys are busy over there at Corteva. When are we going to get the organic weed control? Any thoughts on that?

Dave Hillger 29:56
Organic weed control? We have some other biologicals in our lineup, but we don’t have an organic weed control yet.

Beth Berry 30:03
No! I get asked that all the time. Martha Stewart will post, “Oh, you just use vinegar. It works great.” Martha, it really doesn’t. I’ve tried that.

Justin Stewart 30:13
We’re not there yet.

Beth Berry 30:14
That is a fact. Well, this is a wrap. My name is Beth Berry. I’m Ahead of the Curve on Turf’s Up Radio with my buddies Justin and Dave from Corteva. You told us all the things about pre-emergent crabgrass control. We’re off to a great year. I know where you can buy Dimension. You can buy it at Advanced Turf. We’d love to sell it to you with the support of you all. Thanks so much for being our partner. It’s been a terrific relationship.

Dave Hillger 30:38

Beth Berry 30:38
And we look forward to introducing these new upcoming products.

Justin Stewart 30:44
Perfect. Well, thank you so much.

Dave Hillger 30:46
Thank you.

Beth Berry 30:46
Thanks, guys. We’ll see you next time.