University Place  Doug Soldat Managing Your Lawn the Wisconsin Way  July 17, 2013 UP898  cc >> Welcome, everyone, to Wednesday Nite at the Lab. I'm Tom Zinnen. I work here at the UW-Madison Biotech Center. I also work for UW Extension Cooperative Extension. On behalf of those folks and our other co-organizers, Wisconsin Public Television, the Wisconsin Alumni Association, and the UW-Madison Science Alliance, thanks for coming to Wednesday Nite at the Lab. We do this every Wednesday night, 50 times a year. Tonight, it's my pleasure to be able to introduce to you Doug Soldat. He'll be talking to us about managing your lawn the Wisconsin way. Doug is a native of Wisconsin. He grew up in Janesville on the Rock River, which is a favorite river of mine, since I grew up on the Rock River down in Dixon. 

He went to school here at UW-Madison. He got his bachelors and masters degrees. He went to Cornell University, where he earned a PhD in 2006. His research was studying how soil phosphorus levels influence phosphorous runoff from turfgrass systems. He is now an associate professor here in the Department of Soil Science at UW-Madison, and he specializes in turfgrass and urban soil management. He advises students here in the turfgrass program and teaches classes entitled "Turfgrass Nutrient and Water Management," and also "Lawns, Society, and the Environment," along with two general turfgrass management courses. His research and outreach program are focused on improving nutrient and water use efficiency of turfgrass. If there's a more valuable crop in Wisconsin than our lawns, let me know, especially when you look at it from replacement value and sweat equity. I hope he's going to tell us how we can have grass that tall without having to mow it. I don't think that's what he's going to be able to tell us, but that's what I'm hoping for. 

Please join me in welcoming Doug Soldat to Wednesday Nite at the Lab. [applause]  >> Thanks, Tom. All right, good evening, everybody. It's a pleasure to be here. I'm Doug Soldat. I'm in the Department of Soil Science, and also with UW Extension. The title today is maybe a little bit misleading, because there's a lot more than just one way to manage a lawn. I think what we do at the University of Wisconsin, myself and my co-workers, is we study all different ways to manage a lawn. We're going to talk about the tips and the tricks that we've learned over the years. Wisconsin's actually had a strong presence in the field of turfgrass science for almost 90 years, so a long history there. 

This is a picture from our turfgrass research station out in Verona, kind of the southwest side of town, adjacent to University Ridge, but not affiliated with the golf course. Here we have the no-mow or low-mow fine fescue. Maybe you've heard that word before, where basically you mow it maybe once a year, maybe not. Right next to that, we have a bent grass putting green, which gets mowed six times a week, at the thickness of a credit card. Believe it or not, we have, even though that's more commonly found on golf courses, we have people in Wisconsin that some of them like to try to grow that in their yard, too. Maybe every year or so, we get a phone call from somebody who says, "How can I do that?" My predecessor always told me how he answered that question. He'd say, "First, let me talk to your wife." [laughter] Then he would explain, do you realize that this takes a mower that costs about $6,000, and it needs regular maintenance, and all this. By the end of that discussion, you know, that's the end of the conversation. So, this is an aerial shot of our research center. We have 20 acres. 

Like I said, we study literally everything you think of. We have prairies there, or restored remnant prairies. We have every type of grass that will possibly grow in Wisconsin, and some that don't, that we try to grow. So, we have all kinds of stuff. There's over 100 studies going on at any given year, and the number of individual plots, probably it comes near to a thousand, so there's a lot of activity out there. Right now, we only have two full-time faculty. It's a really fun place to work. This is one of the biggest and best turf grass research facilities in the US. So why? Why all that effort? Why all this study for something that most of us take for granted? Turfgrass is actually the third or fourth largest crop, if you can call it a crop, as Tom said, in Wisconsin. We have over a million acres of turfgrass in Wisconsin. 

Most of that, as you can see, is in home lawns and roadsides. That accounts for over three-quarters of the turf is found in homes and roadsides. With golf courses, usually when you talk about turf, people just go right to golf courses, but they make up less than four percent of the grass in the state. The value, in 1999, a colleague conducted a survey of the turfgrass industry in Wisconsin through the Wisconsin Department of Ag statistics. They found that it was almost a billion-dollar industry in the state. So a billion dollars spent on maintaining turf, almost three times that spent on the equipment to maintain the turf. We have about 454 golf courses in the state. That's actually a big number per capita. We have more golf courses than almost any other state per capita, public golf courses. It's a very big destination. 

Obviously, we're a tourism state. Most of our golf courses are public. And 92% of the homeowners surveyed rated lawns as being important to them. So, all of us have lawns, and our lawns mean different things to everybody. I'm sure there's as many different opinions on what the right way to maintain that lawn is, as there are people in this room. So, we're just going to talk about some of the things that can help you out. This is one of the first questions we ask in Horticulture 261, Introduction to Turfgrass Maintenance, day one. Turf versus turfgrass. What's the word turf mean? Does anybody want to take a shot at that? How are you going to define turf? We hear it all the time. [inaudible] Soil and the grass together, that's good. 

It's a hard one. All the students look at me like this, too. I don't know. [laughter] Turf is a contiguous community of plants that can persist under constant traffic and defoliation. So contiguous, they touch each other. And under constant traffic and defoliation that will persist. That's a really unique feature. It says nothing about grass. Turf is just a community of plants that are contiguous and can persist under constant traffic and defoliation. Turfgrass is just a grass that can do that. 

So we have over 7500 different species of grasses. Only 30 of them are turfgrasses, grasses that can form a turf. So it's as simple as that. So this stuff at Camp Randall, some people call it turf. That is not turf. That's plastic. That's carpet. That's something else. That's artificial turf. Don't forget the "artificial" part. 

These 30 or so grasses that are really important for our lawns evolved in the Miocene Epoch, which is 24 to 5 million years ago. This is the part of the climate where it got colder and it got drier. The forests have started going away. The grasslands expanded. And horses were all over, a really huge horse diversity. They were eating the grass. The grass had to figure out a way to survive. So this is when most of our turfgrasses came into existence, because they had to adapt to that constant grazing pressure. Most of the turfgrasses that we grow in this state originated in Europe. So this is kind of neat, too. 

This is a study that's talking about human evolution. About six million years ago, at the end of the Miocene, that's another important period of human evolution. These authors studied the coexistence is these turfgrasses and humans, so grass, maybe is in our genes. Of course, I'm pandering to you here, trying to build the case for grass. I do this a lot. But this is probably the more convincing evidence that we have this natural connection with grass. What's this picture from? Does anybody recognize this? [inaudible] Yeah, that's the Windows wallpaper from XP, right? So, you know that they had more than one person involved in picking that picture, right, that's the face of the company. That's the picture they picked. Sometimes, we hear the rally against the monoculture, but there's a deep connection with most humans, with this beautiful, serene landscape. Love it or hate it, I think there's a reason that Microsoft picked that. 

That's my case for how humans are connected to grass. Let's go to Wisconsin. This fellow from Stoughton, O.J. Noer, is probably one of, if not the most famous turfgrass agronomists. O.J. did his PhD in the Department of Soil Science back in the 1920s. He actually developed Milorganite. He decided that it was best that product from Milwaukee, from the biosolids or the sewage sludge, was best suited for growing grass. He went of to become one of the most famous agronomists. He traveled all over the United States for 40+ years. At the end of his career he came to the University of Wisconsin and said, we need to have a turfgrass program here. 

This is about to become a really big industry and we want to be on the forefront of that. So the Department of Soil Science listened to him and in the 1960's the first class of students graduated with specialization in turfgrass management. That program was led by Dr. J.R. Love. He ran the program in the '60s through the mid '80s. He did some really outstanding work on nutrient requirements of turfgrass. Then he turned it over to Dr. Wayne Kussow who's my predecessor in the Department of Soil Science. Wayne ran the program from the mid '80s up until the early 2000's. These two people have taught me a lot. They've been really important to advancing turfgrass science in Wisconsin and throughout the nation. I'm excited to talk about some of the stuff that they've done and that we've learned. 

This is maybe little bit too technical here, but this is a picture of the anatomy of a grass plant. There's one thing that makes grasses this really, really special, turfgrasses especially, is the crown. This is the compressed stem, which is the growing point of the plant, which sits right at or usually a little bit below the soil surface. This is where all the action happens with the grass. It's just this one or two millimeter, you can think of it like a bud. At the top the leaves come out. And they come out constantly. The cells are dividing and shooting out new leaves. And the bottom of this crown right here is where the roots come out. And they come out constantly. 

The sides of this, on the side of this crown, are axillary buds. These actually break off to form new plants. This is the growing point of the grass. It's not really-- We have grasses and lawn that are perennial, but these things don't really live that long. This particular crown might only live a year or two, but because it's dividing and splitting off, it's constantly regenerating itself. So your lawn, just like the cells on our body, it's always in a constant state of renewal. Think of all the other plants you know. How many can you cut the tops off of regularly and have success? This is a pretty cool innovation, to have that growing point for the leaves to be down low where the animal of the mower can't get it. There's just another shot of the turfgrass crown. You can never see this with your eye. 

The trouble is, if somebody says, is my grass dead? I know the answer is, well, is the crown alive? But you can almost never see the crown. You can't teach somebody to see the crown. So it's really, really difficult. Last year with the drought we had dead lawns all over and they'd say, is it dead? The best way to tell is to take a plug, put it in some water, and wait two weeks to see if it greens up. People usually don't like that answer, but unfortunately that's the case. The leaves can die back, the roots can die back, but as long as that crown or that bud is alive, the grass is going to come back. We talked about those axillary buds on the side being really important. When it splits off to form new plants, that process is called tillering. All grasses tiller. The main grasses that form only tillers are tall fescue, ryegrass and fine fescue. 

The problem is with tillering it can only spread the size of about a dinner plate. It's not going to fill in the whole lawn. It's not going to take over. These grasses, when they die, they're not going to regenerate themselves from several feet away. You can see here, this is a grass plant with five tillers. One of these was the original plant and it began splitting off, and then a new plant split off. But it's really not going to cover a very large area. Rhizomes, however, are underground stems that break off of that axillary bud and they can travel relatively large distances. These are lateral chutes. They have nods on them which can generate new plants. 

The main grasses in Wisconsin that have rhizomes are Kentucky bluegrass and creeping red fescue, but creeping red fescue has really weak rhizomes. I almost don't like to include it. The reason Kentucky bluegrass is one of the best grasses for the state of Wisconsin is because it has these rhizomes that allow it to fill in large distances, and move and repair and recover from damage. This is a picture of an actual plant. You can see the difficulty in identifying the crown. It's usually buried within the leaf sheaths and roots and all kinds of stuff, but here's this big, thick rhizome that's shooting off of a dormant Kentucky bluegrass plant. Now this was taken last year during the drought and you can see the plant doesn't look too good. Is this plant alive or not? I'm not sure. The crown might be dead. But chances are this rhizome will regenerate from these nods because it's buried down deeper in the soil. 

There's probably a little bit more moisture. It's cooler, it's more protected. If this plant dies, in three or four weeks we're going to have new plants arising from this rhizome. That's one of the lessons that we learned last year from the drought is that Kentucky bluegrass survived a lot better, and recovered a lot better, than some of our other grasses. How about this one? This is a favorite, right? The reason quackgrass is one of the worst weeds in lawns, in agriculture, in everywhere, is because it has some of the most aggressive rhizomes around. These rhizomes make Kentucky bluegrass look really weak. They go down really deep. You think you can kill it, but it keeps coming back because of these rhizomes that have nods, that have the ability to generate new plants. The reason quackgrass is so tough is because of those rhizomes. Okay, at O.J. Noer Turfgrass Research Facility out in Verona we evaluate hundred and hundreds of different varieties of grasses. 

These are all different types of tall fescue. We go out there and look and see how they're doing. Then we give that information back to the breeders who make further selections on what to continue working on and what to bring to market, and things like that. There's a lot of variety within each species of grass. I'm going to show you a little bit of our research on different types of grass under different management scenarios. There may be people in here-- Half of Americans do not fertilize their lawn or control weeds. They only mow. Let's just show our hands. How many people fall into that group, just mowers? Then raise your hand if you're not in that group. That's almost half. 

No fertilizer applications. The pictures from this study are about five years after we planted these grasses. We did no herbicides, no pest control. The only thing we did to these grasses was fertilize them either never, two times a year, or four times a year. This is a common Kentucky bluegrass. Where did most of our grasses come from? Forage, forage grasses, agricultural grasses. Well, what's the problem with forage grasses in a lawn situation? They grow too much. They're too aggressive. They're made to produce biomass. The turfgrass breeders, really starting in probably the '60s, started making grasses shorter and grow slower, and darker green, and all these things that you'd want in a lawn grass. 

So when I say a common Kentucky bluegrass, this one is more closely related to the forage type. Okay? You can see that this one doesn't really look that much different. It doesn't react to that fertilizer. It looks pretty decent at the zero applications. It doesn't look much better at the four applications. It just hangs out there and does it's thing. This is the grass that most people will say, we don't want. This is the premium stuff. Okay? This is what the breeders have done over that 40 or 50 year period. They've made this grass slow growing, they've made it dark green. 

And guess what happens when you don't fertilize it. It completely gets taken over by weeds. Now we realize that it's not, like Tom said, I want a grass that just sits there and I don't have to mow it. The problem with that is that there are other plants that will compete for those same resources. If we plant a grass that's not going to grow, the problem is the weeds are going to overtake it. Some of these grasses that have been selected for, maybe their beauty or their short stature, don't do well under low maintenance conditions. These are both -- Kentucky bluegrass. We can go from that to that just by that growth characteristic. Now the pendulum has sort of swinging back. The grass breeders are realizing that we need a grass that's somewhat competitive. 

Will mowing ever go away? I think probably the answer is, no, unfortunately. Maybe half of us are going to leave now. For that grass to be competitive with weeds it has to have some aggressiveness and some growth characteristics associated with it. Just another shot of the same plots. There's no herbicide involved at all in this. One of the things we say is, nitrogen is the best herbicide. By applying nitrogen fertilizer you're increasing the grass' growth rate which allows it to out-compete weeds. This is perennial ryegrass. It's really not well adapted to Wisconsin. It likes to die in the winter. 

It likes to die in the summer. [laughter] Yeah, not your best choice. But it's really popular with sports fields because it germinates quickly. They just keep putting the seed out. It is widely used in sports turfs. But this has the same problem as Kentucky bluegrass. You can see, if you don't fertilize it, you get really quick weed invasion. Okay, time for some better news, fine fescue. Fine fescue is a collection of four, five, six different species of really, really closely related grasses. They're so closely that we have a very hard time identifying them in a field, so we just put them in a group called fine fescue, sometimes fine fescues. 

You can see that these grasses do really well under low maintenance conditions. This looks good. It's green, no weeds. You're thinking, that's the grass I want. What's the problem with fine fescue? It doesn't like a lot of traffic. If you've got people walking on it, it doesn't do well. If you have lawn that just gets mowed it's going to be fine. You put kids out there, and a dog, it doesn't like that. The other thing fine fescue doesn't like is wet soil. It does good in dry conditions. 

It does well in full sun, it does well in shade. But as soon as you put the wet into the equation, fine fescue tends to go away. So traffic and wet are bad combinations for this grass, but other than that we're looking pretty good. Tall fescue is a newer grass. This grass actually became more popular during the drought of 1988 when lawns died all over the Midwest and people said, we need a different grass. We need something that has better drought tolerance. Tall fescue is an important forage grass. The breeders in the last 30 years have been making it-- Guess what they've been doing to it. Making it shorter, making it dark green. But in 30 years you can only do so much. 

This is still a pretty aggressively growing grass. You can see here, with no fertilizer for about four or five years, it's really still out-competing the weeds. The problem with tall fescue? It doesn't like ice. It'll do fine in cold and snow, but when you start getting ice accumulation it goes away. It's great with traffic. This is one of the best grasses you have. If you have an area that gets worn out all the time, this is a good choice, as long as it's in an area where ice isn't going to accumulate. This is a new one. We don't see too much tall fescue in Wisconsin. But you can find this on the shelves, and it's becoming more and more popular. 

It has really deep roots which, obviously, it was breed for, so it can withstand the drought. I planted this in my yard in 2006 when I moved in because I wanted to learn more about it. Guess which yard mine is. [laughter] It's on the right. It turns brown in the winter. This is not dead. This is the way I keep the neighbors from asking me questions all the time. They see how ugly my lawn is in the winter. This is Kentucky bluegrass on the left. It has a better color retention. 

Tall fescue tends to get really brown and look ugly. It greens up a couple weeks later. But like I said, it's got a lot of positive characteristics to it. The spot in the back of my house where the sump pump came out and ice accumulated, there's no way it would grow there. But especially in the front where it's sloped and full sun, it's doing really well. It's a good grass. Okay, I'm going to show you some more pictures from a different study. This is really low maintenance. Maybe this is more your style. All we did to these plots was mowed them once a month. 

That sounds pretty good. There's no irrigation, no fertilizer, no pest control. The positive was the soil was really good. Most people don't have really good soil. I just want to point out that this was a deep, fertile, uncompacted soil that we planted these grasses to. We literally just put down the seed and walked away. There was no irrigation during that period. This is what the results looked like after two years. Chewings fine fescue is one of those fine fescue. Hard fescue is another one. 

It's very closely related, but you can see the Chewings fine fescue looks a little bit better than the hard with essentially no maintenance. Here's hard fescue, and then we planted some Kentucky bluegrass. There's really no Kentucky bluegrass left in this plot. Kentucky bluegrass is going to be a higher maintenance option. These fine fescues do pretty well under really, really low maintenance conditions. Chewings fine fescue here on the left. There's just a few weeds coming in, not too bad. Tall fescue is on the right. Again, tall fescue showed some really positive responses to these low maintenance conditions. The tall fescue and the Chewings fine fescue are good for this really minimal, low maintenance style. 

But there's always a caveat, right? There's no perfect grass. This was really interesting. The text books all say fine fescue is one of the most drought tolerant grasses. They all say that. In Wisconsin in that drought that we had fine fescue died more than any other grass, and it did not come back. I think that has something to do with the crown. Fine fescue gets, not the technical term for it, puffy. I don't know what. It gets clumpy. The crowns get elevated above the soil surface. 

The soil acts as a really great insulator, so you want to keep those crowns buried in the soil. Fine fescue has a tendency for those crowns to get elevated. Now we have elevated crowns and we have intense heat and extreme drought. Those crowns died. And fine fescues don't have very strong, or any, underground rhizomes. We had a lot of problems with fine fescue in extreme drought. If you have this grass in a dry area you need to pay attention to lengthy drought periods to make sure that this doesn't happen. This is my neighbor's lawn. They had a really beautiful stand of almost 50% Kentucky bluegrass, 50% fine fescue. You can see where the Kentucky bluegrass is. 

It's green. This is after the rains came back. You can see where they lost the fine fescue. The good news is, I should have brought in a picture from today. Their lawn is almost fully recovered, but it's all Kentucky bluegrass. Those underground rhizomes that are all throughout this lawn generated new plants. Their fine fescue is gone, but their lawn regenerated with the Kentucky bluegrass. You can see at the bottom, this is my tall fescue that's doing pretty well. At the O.J. Noer Center we built what we call a rain-out shelter. It basically sits on railroad tracks and when it rains we move it out over the plots. 

Usually in Wisconsin we're getting rain like this year. It's been extremely wet. This is a way to ensure that we can study drought responses of grasses every single year. We think water use is a really critical issue. I'm going to go through some pictures of some of these different grasses and how they responded under drought conditions. Here's a picture of the grasses during the dry-down. You can see that some of them are quite green and some of them have checked out. We have this light box that allows us to take pictures from the same height and the same light levels. Right now, this is prior to drought, and I'm going to click through every week. We're going to track the progress of these five grasses. 

We have two creeping red fescues, that's fine fescue, on the left. On the right we have two different types of tall fescue. That's the grass that I have in my yard that we're planting because it has drought tolerance. In the middle we have a drought-resistant Kentucky bluegrass. We like Kentucky bluegrass because of those underground rhizomes. They all look really nice prior to the drought. This is after four weeks. How many people last year, after four weeks of drought, how many people had lawns that looked this nice after four weeks? Almost nobody. In fact, driving here today I'm amazed at how much brown grass we've seen after just seven or ten days of no rain. The difference here, how we can go at our research station four weeks without really substantial browning, is all related to that quality of the soil. 

We'll come back to that, but the depth and the quality of that soil allows those roots to grow down deeper. That gives it much more access to water, and allows that grass to stay greener for a longer period of time. The most important thing you can do is look to improve the quality of your soil. But anyway, five weeks, it's starting to get brown. The tall fescue down in the corner, the SR8650, still looks green. It gives us an extra week of green grass. The Speedway tall fescue is out. Actually the SR2284 Kentucky bluegrass still has a little bit of green left in it. The creeping red fescues are almost completely brown. At six weeks they're all out. 

Really we're talking, the biggest difference that we can find is about a week, or seven days, of green tissue. Then we watered it. One week after watering and this is the difference. You can see that the two grasses that retained their green the longest bounced back the strongest. That's not too surprising. The two red fescues on the left have substantial amounts of brown. Some of those spots were indeed dead. Three weeks after watering you can see some of the brown, especially in the Boreal creeping red fescue. There's some dead spots. But the Speedway tall fescue mostly came back. 

So from one week, pretty brown, to three weeks, we're all green. I think, from this research, what I can take away, is that the drought resistant Kentucky bluegrasses are still probably the best choice for Wisconsin. And of course we can't evaluate every single grass under this specialized equipment because of space issues, but we're working to develop that database, to identify the best grasses for lawns in Wisconsin.  There's work that's going on to look for new species, or new genes in grasses. This is a study from Rutgers University where they went to Yellowstone Park and they found some turfgrasses that were growing right next to a thermal vent. They grabbed it. It's not suitable for commercial use at this time, but they're looking at finding grasses that can grow in soil temperatures of over 100 degrees. These are cool season grasses. Not the ugly stuff that they're growing down in Florida, but the creeping -- grass and these finer textured grasses that we're used to in the north. Okay, trivia time. 

Maybe this picture's a little hard to see in the room. You basically have a square of completely drought burnt out grass. Around it it's surrounded by green, lush grass. Who knows what that might be from? What do you think? >> A tent. >> A tent, that's usually the first answer. Somebody put a tent there. But how can you put a tent under trees? This is a line of trees here. Anybody else got any thoughts?  This is what happens when somebody trenched in a hole to put some irrigation wire in. When they did that they cut the tree roots. This is the effect of just removing the competition of those trees. 

Simply that. That shows how much-- When we think about, why doesn't grass grow under the tress. Obviously, it's because of the shade. But this is heavily shaded too. It just show how much of that poor performance is attributed to the competition for water with the tree. Yeah, Tom. >> How deep was the trench cut? >> The trench was probably about two feet, something like that.  So it's surface competition for water. It's kind of fun to look at that stuff. All right, so how much should you irrigate? If you want to keep the grass green all week, a really quick, hard, fast rule of thumb is about one inch per week. 

If we did an inch per week every week that would just be really, really way too much water. In Wisconsin we get rain and we have to account for that rain. The grass uses about an inch per week. If we have no rain for a week an inch of irrigation will keep that soil at that level. To keep the crown alive-- Grasses have this wonderful dormancy feature. The leaves can die back. They can go brown and still survive. The question is always, for how long? When the leaves are all brown the water use drops off rapidly. The question is, how much water do you need to apply to keep that crown alive? That was the million dollar question last year, when to irrigate. Usually we say 60 days. 

The grass crown can survive 60 days. But you know what, it makes so much of a difference of how good your soil is. 60 days is no problem in an uncompacted, deep soil. The second you have two inches of soil on compacted clay, it could be as little as two or three weeks. Really, soil has a lot of do with it. What we say in general, is keep that crown alive, maybe a quarter inch of water every seven to 14 days to keep that crown alive. We have a picture of a can of tuna here because this is a good way to measure how much irrigation you're putting out. It's pretty simple. Just make sure you take the tuna out first. [laughter] You have the flat, straight sides, a flat bottom. 

You run the irrigation system for-- you know, keep track of the time and look at how much water, how deep the water is. That will give you an estimation of how much water you apply to the lawn. It's best to put it down in larger doses than smaller doses. If you have an in-ground system, the best thing to do when you get it is turn it off. That's what I tell everybody. One of the biggest problems we have with lawn diseases and all kinds of issues is over-watering. That is usually associated with people with these set-it-and-forget-it systems. The best thing to do is turn it off and just use the system manually like you normally would. The best time to irrigate is when you footprints. We just started to see them a couple days ago around town. 

Right here, when you walk through the lawn, if that grass doesn't spring back up in a reasonable amount of time, it's stressed. This would be the perfect time to put down an inch of water if there's no rain in the forecast. This is the worst time to do what this person did, go out and mow. Mowing is like the biggest stress to the grass, and the grass is already under a whole bunch of stress. This is what the lawn looked like the next week. There's areas where those leaves died, where the wheel mowers went and even where the footsteps went through. We'll get back to mowing a little bit. We'll talk a little bit about keeping nutrients out of the lakes. This is a really important area, and one area Wisconsin's been a leader in for years. When we look at phosphorous losses from urban and rural areas, maybe you think phosphorus is a problem in agricultural areas because of soil loss and manure and all that. 

But the USGS did a really neat study were they looked at urban and rural watersheds. They found that the phosphorus loss form rural watersheds was about half a kilogram per hector. If those units don't mean anything to you, don't worry. Urban areas was about the same, about a half a kilogram per hector. So basically we're seeing the same amount of phosphorus loss from agricultural areas as we see in urban areas. That's kind of surprising. Where's the phosphorus coming from in an urban area? One of the first things that started happening maybe ten or 15 year ago is municipalities began banning the application of phosphorus fertilizer to turf. That sounds reasonable. If that's an important source of phosphorus that gets applied, maybe we shouldn't apply it. Phosphorus containing fertilizer is prohibited in the state of Wisconsin unless you have a soil test showing a need for it. 

If you're establishing a new lawn phosphorus is a really critical part to get that lawn thick as fast as possible. There also are exemptions for natural, organic fertilizers. We study how much phosphorus get lost from fertilizer applications. We also study what the right amount should be in the soil. When you send that soil test into the lab how do they know that the soil is low, medium or high? This is the type of research that's required to establish that. You can see this purple, it almost looks like a drought response in these plots. They have three or four parts per million phosphorus. These two up here are just slightly better at five parts per million phosphorus. Then, just like a light switch, at seven parts per million the grass looks great. That's how we know to tell the soil testing lab, hey, if the numbers come back above this certain level, that's enough phosphorus. 

It's harder than that because it's different for all different soil types and grass types. This is just one example of a phosphorus deficient study that we ran. In general, you want to have your level of phosphorus in the soil as low as possible, but you want enough for plant health. Phosphorus is a really important nutrient, and soil testing is the best way to estimate for it. The main way that phosphorus gets into our lakes is through sediment. Phosphorus binds really tightly to soil. That's why we can soil test so well for it. But when that soil washes away, it also carries away a lot of phosphorus. On the flip side, turfgrass is a really good control method for keeping soil in place. In fact, in agricultural areas where they're trying to minimize phosphorus losses grass waterways, grass filter strips, are a really big management practice. 

Dense stands of grass reduce runoff. They reduce the sediment losses. They reduce nutrient losses. They actually increase the carbon in the soil and increase the groundwater recharge. This is a study from the Baltimore Ecosystem study. It was a really big NSF funded project where these researchers studied all these different components of urban systems. They found that the nutrient cycling in lawns is complex, and the effects of lawns on water quality are probably less negative than anticipated. Basically, they're saying because grasses are green early in the spring and late in the fall they have the ability to take up more nitrogen than other crops. They didn't find high levels of nitrate leaching or nitrate oxide flux, similar to forests. In the '90s, Dr. Wayne Kussow, in the Department of Soil Science, did a study that really opened my eyes, and probably got me interested in becoming a researcher. 

He compared different types of grasses, no fertilizer for two years, or Scotts or Milorganite three times a year. He looked at the amount of phosphorus that ran off of those plots. Surprisingly, he found that fertilizing three times a year resulted in less phosphorus loss from the lawn. Even though he's putting down phosphorus fertilizer with those two treatments, they had less phosphorus than no fertilizer. How can that be? It's related to the density. It's related to the amount of water that moves off those plots. If you have a dense groundcover, that's going to slow that water and allow more in infiltrate. It's a little counter-intuitive, but it makes sense when you think about the mechanisms that are really going on. That research now has been replicated in other sites. This is from the University of Minnesota. 

The plot of the left here has no fertilizer, the plot of the right has been fertilized. This was done in 2010. The results were, after three years the non-fertilized turf had greater runoff than fertilized turf. The new component of this study was that using zero phosphorus fertilizers did result in less phosphorus than using a complete fertilizer. That adds some credence to not applying phosphorus in situations where it's not needed to increase the grass growth. Where is the phosphorus coming from in the urban landscape? I think this type of sediment loss is probably the number one factor. Controlling sediment loss is going to be a really important way to keep phosphorus out of the lakes. This is a picture of a construction site. This is the curb here. It's just buried in soil from a major runoff event. 

And because we have these streets and sidewalks and roadsides, it's a direct conduit. It can't get trapped anywhere. It's going to end up in the source. This is my yard. I moved in in 2006. It was a new construction. This is what the soil looks like. I didn't go looking through Google for the absolute worst picture of soil. I just walked out my front door and took a picture. This is what you get. 

There's tire tracks in here. There's a pile of concrete. The way we treat urban soils is not fair. That was in November. We come back in April, and now look at this. This is the subsoil. This is almost like concrete. We have two inches of topsoil that's put back on top, right? So we're expected to grow a thick, dense, healthy lawn that's going to help water infiltrate when this is our starting condition? This is really, I think, the main issue with urban hydrology. I give talks to master gardeners and say, okay, my wife wants to grow a garden in the backyard. I can just plant the tomatoes right in that, right? They laugh, and say, no, you can't do that. 

You build a raised bed. Okay, well, why do you build a raised bed? You need soil to grow the tomatoes. Well, grass is a plant. It's plant discrimination. Why do some plants get the luxury of having a nice, raised bed? Look at this picture. Look at the grass here, it's struggling. It's not struggling because it's a grass. It's struggling because there's no soil there. Of course, the reason you build something like this is because soil is really important to plant growth. But the conditions that we do that now don't allow it. 

What can you do about it? Unfortunately, there's really not a lot. One slow, long-term solution is applying compost on a regular basis. A quarter to a half inch spring and fall. We've found that is a really good practice to slowly build up the health of that soil. Water infiltration rates improved after three years of study from the control which received nothing. Three to five inches per hour up to 9 and 17 by adding compost regularly. Okay, so let's go to best practices. Again, the Wisconsin way to manage your lawn-- If there's five million people in this state, there's five million different ways to do it. In general, the University of Wisconsin recommends fertilizing around Memorial Day, earlier than that there's nitrogen that's left over from the winter that's being broken down and utilized. Plants are naturally growing good. 

Wait until Memorial Day. July Fourth is an intermediate timing. It depends a lot on the weather. If there's water around, if the temperature's are moderate, it's a good time. Consider an organic or a slow-release fertilizer at that time to provide a slow-release nutrient source. Then in the fall is probably the most important time to fertilize to recover from the summer stress and prepare for the winter. About the time of Labor Day is a good time to consider that application. We used to recommend up until Halloween, but our research has shown that that's probably not a very efficient application. Okay, if you have a shady lawn or an older lawn it's going to have a lower nitrogen requirement. You can absolutely get away with looking at Memorial Day and Labor Day. 

Skip that second time. Younger lawns are going to have a higher requirement than older lawns. And shady lawns will have lower requirements than full sun. Mowing is the most important thing though. Most people just mow. If you're going to do one thing, sharpen your mower blade. Keep very sharp mower blades and mow high. Those are the two most important things. Like I said, mowing is a stress and we do it every single week. You'd rather get cut by a sharp blade than a dull one. 

Turf heals faster, we have less disease, and it has a better appearance. Also, there are decreased weeds. The roots are deeper. If you have the soil to accept them, mowing higher is going to result in deeper roots. All around, mowing higher with a sharp blade is really, really good. Weed control, people are going to be all over the board on this. In general, you have two types of weeds. You have annual weeds that grow in the summer once a year, and then you have the perennial weeds that survive year-round. The best time to get out the annual weeds, especially crab grass, is around the time forsythia are in full bloom. If you see these yellow bushed lighting up, that means the soil temperatures are right in the right spot to control crab grass. 

Perennial weeds, it's best to wait until about the first frost. These perennial weeds can germinate up until that point. Let them germinate all throughout the fall, then in the very late fall, the best time to get perennial weeds is around the time of that first hard, killing frost. Like I said, nitrogen fertilization is going to help out-compete those weeds and keep things low. Insect control is difficult. We don't have a heck of a lot of insect control problems in Wisconsin, but identifying the insect and the lifecycle of that insect are really critical. There's lots of different options. I always recommend getting your pest identified correctly and getting a recommendation from a diagnostic lab. The most common insects are white grubs and the best time to control them is around the Fourth of July. Okay, core cultivation. 

If you're a golfer you've seen these holes in the ground. You see people in the neighborhood pull out these cores. This is important, but it's a temporary, Band-Aid solution. We're removing the compaction or the thatch of the top one of two inches. We're not effecting that deep, deep systemic problem of the deep compacted layer. We are fixing the surface problem. This isn't going to solve all your problems, but it can provide temporary benefits to lawns, especially ones with high traffic. The best time to do this is in the fall. In the spring you're creating too many gaps for the weeds to germinate into. If you have dead spots this is the way to go after it. 

This is a slit seeder, and you can see the knives on the bottom of this machine. It creates these little slits. You can go over and put the seed into those slits and cover them up. It's a fairly effective technique. But remember, the reason your grass died probably was because there was something wrong with the soil. This is nice and easy. This is really difficult. I'm not going to do that, but sometimes this is really what's needed to effect that. Till in some compost, get that soil, fix your root zone, remove the compaction as deep as possible. You'll be amazed at the difference that you can make. 

The soil properties, and we don't see it so we don't think about it, but they control a lot the plant growth. We have a turfgrass diagnostic lab at the O.J. Noer Research Station. There's a manager there. The manager consults with all the facility members and staff on problems. You can submit a sample for $20. Walk in there one day, chances are your problem will get cleared up for free. It's a really great resource and I encourage you to utilize it if you have a problem. In summery, some maintenance is a good thing from an agronomics perspective, from an environmental perspective. A lot of it has to do with the right grass. I think what we learned, from especially last year, Kentucky bluegrass is a really good choice for Wisconsin. 

Those fine fescues and tall fescues are interesting and they have some really good properties, but Kentucky bluegrass still deserves to be the number one grass in the state. Then finally, don't forget about the soil. Most of the problems, 70% of the problems that come into here, are related to the growing environment or the soil. With that I will conclude. Thank you very much for your time. We have the University of Wisconsin Learning Store, a great resource for more information on lawn maintenance, lawn establishment and renovation. If you're interested in alternative strategies we have publications for that. And as always, feel free to give me a call or e-mail with any of your grass-related questions. [applause]