Researching Our Topic
We spent two periods at school everyday for about 4 days simply researching our topic. We found a lot of good sites which are mentioned under references. If you want more information about soil quality testing or other areas, visit the links provided.
Talking to the Experts
We contacted a soil scientist - Louis Schipper. We asked about our research questions to obtain a better understanding of the subject and found a lot of helpful information with him.
Us: What is your job in the field of soil science?
Louis: Right! Big question! Let’s see... I’m interested broadly in how you can use soil to protect the environment while producing food, ok? So soil supports all food production, right? Except for fish and stuff like that in the sea. But actually all the nutrients that go in the sea that feed fish and that, that has come down rivers, so in some ways, it’s even supporting the ocean but most of the food that we eat, it is grown from, uh, supports food that we then eat, right? So the vegetables and the animals and all that sort of stuff, so that’s great. But the other job that soil has is avoiding unwanted impacts on other environments. So soil can function to protect water, plants, and it can protect the air, and it needs to look after itself so it can continue to produce food. Make sense? Ok, so my job is to try and figure out how to work with soil or how people work with soil to maximize that environmental performance the way that the soil stops nutrients getting into waterways, stops greenhouse gases getting into the atmosphere and make sure that it can continue to support plant and animal growth and function. Yeah?
Us: So what makes healthy soil? Such as the nutrients in it?
Louis: Right. So, the thing about healthy soil is that it depend on what you want to use it for. Because, different soils are good for different things, right? So if you want to grow vegetables, you want have what’s called good soil tilth, which is if you look at soil, go out and have a look sometime, and have look you’ll find little crumbs about that big *gestures to a small circular shape about the size of a pinky fingernail* of soil that kind of hold together? And if you have that nicely distributed throughout the soil, it’s very easy for plants to grow their roots through that, and those little balls (they’re called aggregates) they hold on to nutrients, they hold onto soil organic matter which is really important to give you good food production, right? But, if you want to grow kauri trees, or a native forest, you actually want really low nutrient content in the soil, and maybe poor drainage so it’s wet all the time, which is not a good thing for growing vegetables, alright? So, so what makes it good soil depend on what you want to use it for. If you want to grow vegetables, you need this good soil tilth, lots of nitrogen, phosphorus, you need lots of organic matter, organic matter is the broken down bits of roots and leaves, insects and all that soil that hold on to the nutrients that binds the soil together acts like a bit of a glue, so that’s if you want to grow vegetables. If you want to grow different things like kauri forest or natives forest, you want something that has much lower nutrients in it and might be more poorly drained and more wet and that’s good for those trees. So it differs. That make sense? You’ve got to match the soil to what you want to use it for. The key properties are the amount of nutrients you have, how much water it has, and what sort of a structure it has, how it’s kind of clumped together. Alright?
Us: Do you know if there are any problems with bad nutrients or something in the soil at the moment?
Louis: Sure. If you have too much nutrients in the soil, and we put a lot of fertilizer on some of our agricultural land, that supports production and makes cheap food for us (and we all like to eat). But if you get too much nutrients, they don’t stay where they’re put. Particularly nitrogen but also phosphorus - they’re two of the key nutrients you need for growing plants. For nitrogen, it will what’s called leach down through the soil profile, so it will move down the soil and hit ground water which might be a meter or tens of meters below the surface. And then it will move with that ground water to streams and rivers and lakes and then pop up there. Now what you’ve done is the nutrients and fertilizer you put on to the land is now, some of it, in waters. And there it acts as a fertilizer as well. Right, so then you get algal growth, and you don’t want algae growing, you know you get green looking kind of rivers, and you don’t want to swim in that, ay? And it’s not good for drinking. So if you have too much nutrients it’ll move away from the land and end up in the waterways. And then of course there is unwanted algae growth which then kills fish. Yeah, so you know United States, in the Mississippi basin, which is this huge area that goes back up off the Gulf of Mexico and all the Gulf of Mexico drains down the Mississippi and ends up in the Gulf of Mexico. Every year there’s is an area, about the size of the Waikato which becomes what’s called the ‘Dead Zone’, where there’s too many nutrients that have gone in there and you get these big algal growths and then the fish are not very happy. So it’s a quite a large global issue. If you have too much nutrients, it will leave the land and end up in waterways and causes pollution. So it’s about balance you have got to have enough nutrients if you want cheap food, but too much nutrients and it ends up in the waterways. So the nutrients and fertilizer are not bad, it’s about how much. It’s like sugar.
Us: How can you tell the state of soil? Do you test it in a lab...?
Louis: Yeah, so again it depends on what you’re looking for. But if you’re looking particularly for how much fertilizer to put on, then you’ll take samples and send to somewhere like Roger Hill’s Laboratories, and they’ll analyze it for specific things particularly phosphorus, and what they call base cations. Base cations are calcium, magnesium, sodium and potassium. And you’ll need all those as well, they’ll test it for that and they also measure for pH which is how acidic or how alkaline it is. Depending again on what you’re wanting, then you adjust the soil. So for example, pH is a really good one. pH is how acidic or how alkaline it is. If you want to grow blueberries, you want to have a pH of about 4, which is quite low, it’s resonably acidic. If you want to grow grass, you want to be around pH 6. If you want to grow truffles, do you know what truffles are?
Us: Yeah..they are-
Louis: Yeah truffles are a fungi that grows on oak trees, on the roots, and they form these little balls and like those little balls they like tat might be worth a few thousands of dollars cause they plane it onto food cause it releases aromatic...i don’t know, something. So if you want to grow truffles, you need a pH of the soil at around 10. So you test the soil, and find out what you have got, and then you have to figure out if that matches with what the plants you want to grow, want. So it isn’t like there is one soil that is great for everything.
Us: Is there a way to analyze the quality of soil without using lab testing?
Louis: Yes, there’s something, but it’s not going to tell you about nutrient content too much, but there are two different ways. You can test the soil to find out how much nutrients you’ve got or you can look at the plants. If the plants aren’t looking very well, it’s quite likely that there is a nutrient missing and very good people, who have done this for years with pastural systems, you know like agriculture with cows and stuff, they can usually tell nutrients are missing by looking at the plants. Like for example, tomato plants will go slightly purplish on the leaves if they are potassium deficient. So you can tell if you go into a pasture and you really know what you’re doing, I don’t do this stuff, you can look at the plants and you’ll get a sense that “Oh, this is probably deficient in this or that or this” Alright? So that tells you about nutrient status without testing the soil. So the other thing you can do to look at soils is something called a visual soil assessment (VSA) and you can look that up online it’s in the science learning hub, I don’t know if you’ve looked there, but it’s done by the university of Waikato and there’s a whole section there on soils and farming that’s got exercises you can do and stuff. One of those exercises is the visual soil assessment. So you can go on there and you can see how to do a VSA. All that requires is a spade, and essentially a tub. And then basically what you do, is you get out a chunk of soil about that big * roughly 20cm long* of topsoil and then you drop it 3 times in a row until it falls apart and then you look for the aggregates ( the little crumbs of soil) and you organize it and then you compare it against sample photos and that will then tell you about the physical health of the soil. So look that up, Visual Soil Assessment. My wife wrote that exercise and its based on some work that was in a science organization in New Zealand. So it’s a really nice way of doing it
Dr Kahan: Oh, are you recording? Can I just have a second? ARRRRRRRR(blender) Great. Thanks.
Us: Why in you opinion is good soil important for a sustainable world?
Louis: Well, I mean, because all of our food comes out of healthy soil. You need to look after your soil, right? And also, if you want to have all that food production without all that environmental impact or by minimizing that environmental impact you’ve got to have good soil. And one do the funny things about good soil is, well, do you know why Hamilton is built where it is? It’s because we have great soil! And in Auckland there’s some great soils and many of the bigger cities of the world. Or the most important cities in the world. Or where people originally settled because they went “Ahhhhhhhh, there’s some really good soil here. We can grow lots of food here. So let’s stay here!!!” And so they built a town there and then the town gets bigger because they produce lots of food and all that sort of stuff. And then the unfortunate thing id that, we see this everywhere in the world, is that the city gets bigger and bigger and bigger and goes over all the good soil. So you lose your best soils. So that’s happened in Hamilton and it’s happened up in Auckland as well where a lot of houses are now being built on excellent soils for growing food. So in terms of a sustainable world, food production and food comes from soil.
Us: You said something before about greenhouse gases...
Louis: So, with greenhouse gases there are three main ones. Well, the three main ones we can affect, which are: carbon dioxide, nitrous oxide, and methane. And all of those interact with soil. So, the organic matter that I was mentioning before in soil, that’s just carbon, and that’s exchanging - the plants take CO2 out of the air and convert it into leaf material and roots and that enters the soil and that can be stabilized in the soil. So, you might end up sort of banking CO2 in a different form as organic matter in the soil. So that will be good, because you can get CO2 out of the atmosphere. And in fact, of the fossil fuels that we’ve burned we don’t find as much CO2 in the air as we think there should be. But a lot of that because it has been captured by plants growning and it’s gone into the soil. So that’s one thing soil does. Nitrous oxide gets produced in soil. It’s a really important greenhouse gas. It’s produced and consumed in soil so if you can make sure that you minimize the production of nitrous oxide, then you can decrease the impacrts of the greenhouse gas. So soil has a very key role to play in managing climate change.
Us: You mentioned that bigger cities had better soil. Do you know where in New Zealand the worst soil is?
Louis: So that then comes down to what you want to use that soil for, right? So some of the worst soils are up in Northland because they’re all really old, and they’re really what they call highly weathered which means you have a really heavy clay soil. So if you want to grow vegetables in it, it’s going to be really tough but it will be really good for growing kauri trees. So there isn’t a worst soil, it’s more about what do you want to use your soil for. There is a worst soil for agriculture, and there is a worst soil for growing native trees, and they are completely different. So it depends on what you want to use your soil for. Does that make sense?
Us: Thank you very much for your time and information!!
Louis: Right! Big question! Let’s see... I’m interested broadly in how you can use soil to protect the environment while producing food, ok? So soil supports all food production, right? Except for fish and stuff like that in the sea. But actually all the nutrients that go in the sea that feed fish and that, that has come down rivers, so in some ways, it’s even supporting the ocean but most of the food that we eat, it is grown from, uh, supports food that we then eat, right? So the vegetables and the animals and all that sort of stuff, so that’s great. But the other job that soil has is avoiding unwanted impacts on other environments. So soil can function to protect water, plants, and it can protect the air, and it needs to look after itself so it can continue to produce food. Make sense? Ok, so my job is to try and figure out how to work with soil or how people work with soil to maximize that environmental performance the way that the soil stops nutrients getting into waterways, stops greenhouse gases getting into the atmosphere and make sure that it can continue to support plant and animal growth and function. Yeah?
Us: So what makes healthy soil? Such as the nutrients in it?
Louis: Right. So, the thing about healthy soil is that it depend on what you want to use it for. Because, different soils are good for different things, right? So if you want to grow vegetables, you want have what’s called good soil tilth, which is if you look at soil, go out and have a look sometime, and have look you’ll find little crumbs about that big *gestures to a small circular shape about the size of a pinky fingernail* of soil that kind of hold together? And if you have that nicely distributed throughout the soil, it’s very easy for plants to grow their roots through that, and those little balls (they’re called aggregates) they hold on to nutrients, they hold onto soil organic matter which is really important to give you good food production, right? But, if you want to grow kauri trees, or a native forest, you actually want really low nutrient content in the soil, and maybe poor drainage so it’s wet all the time, which is not a good thing for growing vegetables, alright? So, so what makes it good soil depend on what you want to use it for. If you want to grow vegetables, you need this good soil tilth, lots of nitrogen, phosphorus, you need lots of organic matter, organic matter is the broken down bits of roots and leaves, insects and all that soil that hold on to the nutrients that binds the soil together acts like a bit of a glue, so that’s if you want to grow vegetables. If you want to grow different things like kauri forest or natives forest, you want something that has much lower nutrients in it and might be more poorly drained and more wet and that’s good for those trees. So it differs. That make sense? You’ve got to match the soil to what you want to use it for. The key properties are the amount of nutrients you have, how much water it has, and what sort of a structure it has, how it’s kind of clumped together. Alright?
Us: Do you know if there are any problems with bad nutrients or something in the soil at the moment?
Louis: Sure. If you have too much nutrients in the soil, and we put a lot of fertilizer on some of our agricultural land, that supports production and makes cheap food for us (and we all like to eat). But if you get too much nutrients, they don’t stay where they’re put. Particularly nitrogen but also phosphorus - they’re two of the key nutrients you need for growing plants. For nitrogen, it will what’s called leach down through the soil profile, so it will move down the soil and hit ground water which might be a meter or tens of meters below the surface. And then it will move with that ground water to streams and rivers and lakes and then pop up there. Now what you’ve done is the nutrients and fertilizer you put on to the land is now, some of it, in waters. And there it acts as a fertilizer as well. Right, so then you get algal growth, and you don’t want algae growing, you know you get green looking kind of rivers, and you don’t want to swim in that, ay? And it’s not good for drinking. So if you have too much nutrients it’ll move away from the land and end up in the waterways. And then of course there is unwanted algae growth which then kills fish. Yeah, so you know United States, in the Mississippi basin, which is this huge area that goes back up off the Gulf of Mexico and all the Gulf of Mexico drains down the Mississippi and ends up in the Gulf of Mexico. Every year there’s is an area, about the size of the Waikato which becomes what’s called the ‘Dead Zone’, where there’s too many nutrients that have gone in there and you get these big algal growths and then the fish are not very happy. So it’s a quite a large global issue. If you have too much nutrients, it will leave the land and end up in waterways and causes pollution. So it’s about balance you have got to have enough nutrients if you want cheap food, but too much nutrients and it ends up in the waterways. So the nutrients and fertilizer are not bad, it’s about how much. It’s like sugar.
Us: How can you tell the state of soil? Do you test it in a lab...?
Louis: Yeah, so again it depends on what you’re looking for. But if you’re looking particularly for how much fertilizer to put on, then you’ll take samples and send to somewhere like Roger Hill’s Laboratories, and they’ll analyze it for specific things particularly phosphorus, and what they call base cations. Base cations are calcium, magnesium, sodium and potassium. And you’ll need all those as well, they’ll test it for that and they also measure for pH which is how acidic or how alkaline it is. Depending again on what you’re wanting, then you adjust the soil. So for example, pH is a really good one. pH is how acidic or how alkaline it is. If you want to grow blueberries, you want to have a pH of about 4, which is quite low, it’s resonably acidic. If you want to grow grass, you want to be around pH 6. If you want to grow truffles, do you know what truffles are?
Us: Yeah..they are-
Louis: Yeah truffles are a fungi that grows on oak trees, on the roots, and they form these little balls and like those little balls they like tat might be worth a few thousands of dollars cause they plane it onto food cause it releases aromatic...i don’t know, something. So if you want to grow truffles, you need a pH of the soil at around 10. So you test the soil, and find out what you have got, and then you have to figure out if that matches with what the plants you want to grow, want. So it isn’t like there is one soil that is great for everything.
Us: Is there a way to analyze the quality of soil without using lab testing?
Louis: Yes, there’s something, but it’s not going to tell you about nutrient content too much, but there are two different ways. You can test the soil to find out how much nutrients you’ve got or you can look at the plants. If the plants aren’t looking very well, it’s quite likely that there is a nutrient missing and very good people, who have done this for years with pastural systems, you know like agriculture with cows and stuff, they can usually tell nutrients are missing by looking at the plants. Like for example, tomato plants will go slightly purplish on the leaves if they are potassium deficient. So you can tell if you go into a pasture and you really know what you’re doing, I don’t do this stuff, you can look at the plants and you’ll get a sense that “Oh, this is probably deficient in this or that or this” Alright? So that tells you about nutrient status without testing the soil. So the other thing you can do to look at soils is something called a visual soil assessment (VSA) and you can look that up online it’s in the science learning hub, I don’t know if you’ve looked there, but it’s done by the university of Waikato and there’s a whole section there on soils and farming that’s got exercises you can do and stuff. One of those exercises is the visual soil assessment. So you can go on there and you can see how to do a VSA. All that requires is a spade, and essentially a tub. And then basically what you do, is you get out a chunk of soil about that big * roughly 20cm long* of topsoil and then you drop it 3 times in a row until it falls apart and then you look for the aggregates ( the little crumbs of soil) and you organize it and then you compare it against sample photos and that will then tell you about the physical health of the soil. So look that up, Visual Soil Assessment. My wife wrote that exercise and its based on some work that was in a science organization in New Zealand. So it’s a really nice way of doing it
Dr Kahan: Oh, are you recording? Can I just have a second? ARRRRRRRR(blender) Great. Thanks.
Us: Why in you opinion is good soil important for a sustainable world?
Louis: Well, I mean, because all of our food comes out of healthy soil. You need to look after your soil, right? And also, if you want to have all that food production without all that environmental impact or by minimizing that environmental impact you’ve got to have good soil. And one do the funny things about good soil is, well, do you know why Hamilton is built where it is? It’s because we have great soil! And in Auckland there’s some great soils and many of the bigger cities of the world. Or the most important cities in the world. Or where people originally settled because they went “Ahhhhhhhh, there’s some really good soil here. We can grow lots of food here. So let’s stay here!!!” And so they built a town there and then the town gets bigger because they produce lots of food and all that sort of stuff. And then the unfortunate thing id that, we see this everywhere in the world, is that the city gets bigger and bigger and bigger and goes over all the good soil. So you lose your best soils. So that’s happened in Hamilton and it’s happened up in Auckland as well where a lot of houses are now being built on excellent soils for growing food. So in terms of a sustainable world, food production and food comes from soil.
Us: You said something before about greenhouse gases...
Louis: So, with greenhouse gases there are three main ones. Well, the three main ones we can affect, which are: carbon dioxide, nitrous oxide, and methane. And all of those interact with soil. So, the organic matter that I was mentioning before in soil, that’s just carbon, and that’s exchanging - the plants take CO2 out of the air and convert it into leaf material and roots and that enters the soil and that can be stabilized in the soil. So, you might end up sort of banking CO2 in a different form as organic matter in the soil. So that will be good, because you can get CO2 out of the atmosphere. And in fact, of the fossil fuels that we’ve burned we don’t find as much CO2 in the air as we think there should be. But a lot of that because it has been captured by plants growning and it’s gone into the soil. So that’s one thing soil does. Nitrous oxide gets produced in soil. It’s a really important greenhouse gas. It’s produced and consumed in soil so if you can make sure that you minimize the production of nitrous oxide, then you can decrease the impacrts of the greenhouse gas. So soil has a very key role to play in managing climate change.
Us: You mentioned that bigger cities had better soil. Do you know where in New Zealand the worst soil is?
Louis: So that then comes down to what you want to use that soil for, right? So some of the worst soils are up in Northland because they’re all really old, and they’re really what they call highly weathered which means you have a really heavy clay soil. So if you want to grow vegetables in it, it’s going to be really tough but it will be really good for growing kauri trees. So there isn’t a worst soil, it’s more about what do you want to use your soil for. There is a worst soil for agriculture, and there is a worst soil for growing native trees, and they are completely different. So it depends on what you want to use your soil for. Does that make sense?
Us: Thank you very much for your time and information!!
Improving the Quality of Soil in the Park
We went and talked to the workmen in Memorial Park. They gave us their perspective on managing soil and gave us some helpful information. They gave us permission to complete VSA's in the park so we then went and completed three VSA's of which the results are under the page 'More...'. The interview with John the gardener is below.
Us: Hi, we are from Dio, and we are doing a sustainability project on soil - soil quality. And we were wondering if we could ask you a couple of questions?
John: Sure!
Us: How do you manage the soil quality around here?
John: Well first, we try to keep spraying to an absolute minimum. We also try to mechanically cultivate where possible. We have a lot of bedding plants around here so we don’t have to spray much at all - we just don’t have the numbers here to do it.
Us: Do you encounter any problems when managing the soil?
John: Not really, it’s pretty much left to its own devices. It’s park land so it’s fairly limited with what you can do with it fairly close to the river. We don’t want to be spreading to much stuff to do much leeching. Yeah, try to keep it to a limit. It looks after itself pretty much. But if the trees get sick and all that, we just treat them all individually. We can do soil tests as well. With the pH levels we can determine nutrient status that way and that will determine whether we need any fertilizers at all.
Us: When a plant is sick or unhealthy, how do you treat it?
John: Well, you can generally tell by the characteristics on the plant whether it has a specific nutrient deficiency, but if there were a whole lot of plants then we can treat that area as a whole but normally, we just use compost - from leaves and grass and food and also mulch which pretty much takes care of the soil. Also, this year we started using a new fertilizer which adds a bit more extra structure to it and it also keeps the weeds down as well.
Us: What kind of pH do you want the soil to be at around this park?
John: For this park, we want the pH to be around neutral (7) or between 6 and 8. Basically, we grow fairly normal plants around here so we don’t have to worry about plants like kauri trees which need a pretty acidic pH value.
Us: Thank you very much for your time, it’s been vey helpful!
John: Your welcome. All the best!
Us: Hi, we are from Dio, and we are doing a sustainability project on soil - soil quality. And we were wondering if we could ask you a couple of questions?
John: Sure!
Us: How do you manage the soil quality around here?
John: Well first, we try to keep spraying to an absolute minimum. We also try to mechanically cultivate where possible. We have a lot of bedding plants around here so we don’t have to spray much at all - we just don’t have the numbers here to do it.
Us: Do you encounter any problems when managing the soil?
John: Not really, it’s pretty much left to its own devices. It’s park land so it’s fairly limited with what you can do with it fairly close to the river. We don’t want to be spreading to much stuff to do much leeching. Yeah, try to keep it to a limit. It looks after itself pretty much. But if the trees get sick and all that, we just treat them all individually. We can do soil tests as well. With the pH levels we can determine nutrient status that way and that will determine whether we need any fertilizers at all.
Us: When a plant is sick or unhealthy, how do you treat it?
John: Well, you can generally tell by the characteristics on the plant whether it has a specific nutrient deficiency, but if there were a whole lot of plants then we can treat that area as a whole but normally, we just use compost - from leaves and grass and food and also mulch which pretty much takes care of the soil. Also, this year we started using a new fertilizer which adds a bit more extra structure to it and it also keeps the weeds down as well.
Us: What kind of pH do you want the soil to be at around this park?
John: For this park, we want the pH to be around neutral (7) or between 6 and 8. Basically, we grow fairly normal plants around here so we don’t have to worry about plants like kauri trees which need a pretty acidic pH value.
Us: Thank you very much for your time, it’s been vey helpful!
John: Your welcome. All the best!
Investigating the Quality of the Soil in Our School
We organised a time and spoke to one of our school gardeners, Roy. He has a good understanding of soil and what can be done to improve it. He showed us around the gardeners' area and explained the process of creating compost with grass clippings. The interview:
Here is a copy of the interview with Roy:
Us: Hi, we are doing a sustainability project on soil and we were wondering if you had a couple of minutes for us to ask you a couple of questions?
Roy: Of course, in fact I can show you the compost I do. Let’s just walk a bit and I will show you. Here are all grass clippings we get. There are so many that we have to leave it in a pile here and then we gradually add it into the soil. And so there are many stages to the compost. This one here is the grain stage, where all the fungi and stuff starts breaking the leaves and grass down. Then after a while, we get to the next one here. Normally, this is where the soil kind of gets turned over and the insects - microscopic bugs get in there. There is still a little bit of grain happening - you don’t want to put your hand in there, but that is really, really hot. See all of the steam coming off? And then this one, see all the worms in there?
Us: Could we take a quick photo?
Roy: Yeah, definitely! And so the worms finish it off, they eat it all up. And that’s just on the surface. As you get down, you get more and more and when I use the loader to move it, you see the worms just crawling out and falling all over the ground and by the time it gets to this next one, it’s just beautiful soil. And so they - the worms - eat it all up and their casting, that’s what they call their poo is actually beautiful for the gardens. The gardeners all use it and I sometimes use a bit of it for the lawns, but I actually have to add other stuff to it, because otherwise it’s just a bit too strong so I buy humus and sand and that allows the roots in the grass to get in there. And as you can see on the grass around the school, it’s taking off quite a bit. And so that’s what I do, you know? Also at the moment, we have got a bit of clay soil which is really hard to get grass to grow on it, and so I put some of this compost on it and after a while it just takes off. So this is where the magic happens *he indicates to the various stages of compost*
Us: So all of this is just grass?!
Roy: Yeah basically, although as you can see there are a couple of sticks and leaves and the leaves - they actually play a pretty important role because they provide potassium. Also the grass and branches and sticks are full of nitrogen. So you’ve got nitrogen and potassium and that’s just really good for the soil and then plant growth. So yeah that’s what I do.
Us: Have you ever come across any problems with the soil in the school?
Roy: Yeah, all around the school it’s the clay. With so many girls walking over it and packing it down, there’s just no accessing of the roots. Clay on it’s own has a lot of good nutrients in it but when it’s just so packed, you have to add compost to it. So that was the biggest problem when I first came here was a lot of the soil was just clay.
Us: Wow..yeah
Roy: So what’s this project that you’re doing?
Us: Well, we’re doing Yr 9 sustainability and we are taking action and stuff so we have been doing VSA’s - Visual Soil Assessments around the parks and so we are looking at different soil types and that sort of stuff.
Roy: Ah yeah well here I want the soil for the grass to be slightly acidic but Judy wants quite a lot of mellow soil so I’m putting in a bit of lime for her that she adds in to her gardens and so yeah.
Us: We were wondering whether we could do some VSA’s around the school?
Roy: What are VSA’s again?
Us: Well, it;s when we dig up a 20cm cube of soil and we look at the structure and the aggregates and we search for earthworms.
Roy: Yeah definitely! Would you do it in different area’s?
Us: Yeah, we would like to do it in places where there is clay soil and stuff
Roy: Excellent. Also there are a lot of areas like by the chapel where I have tended to the soil and so the soil you find there is quite different from the soil you’ll find like outside the Sport Centre. And then also take one from opposite the canteen area - by the big tree - that has quite good soil there too.
Us: Ok, thank you so much!
Roy: Yeah no worries hope it all goes well!
Us: Hi, we are doing a sustainability project on soil and we were wondering if you had a couple of minutes for us to ask you a couple of questions?
Roy: Of course, in fact I can show you the compost I do. Let’s just walk a bit and I will show you. Here are all grass clippings we get. There are so many that we have to leave it in a pile here and then we gradually add it into the soil. And so there are many stages to the compost. This one here is the grain stage, where all the fungi and stuff starts breaking the leaves and grass down. Then after a while, we get to the next one here. Normally, this is where the soil kind of gets turned over and the insects - microscopic bugs get in there. There is still a little bit of grain happening - you don’t want to put your hand in there, but that is really, really hot. See all of the steam coming off? And then this one, see all the worms in there?
Us: Could we take a quick photo?
Roy: Yeah, definitely! And so the worms finish it off, they eat it all up. And that’s just on the surface. As you get down, you get more and more and when I use the loader to move it, you see the worms just crawling out and falling all over the ground and by the time it gets to this next one, it’s just beautiful soil. And so they - the worms - eat it all up and their casting, that’s what they call their poo is actually beautiful for the gardens. The gardeners all use it and I sometimes use a bit of it for the lawns, but I actually have to add other stuff to it, because otherwise it’s just a bit too strong so I buy humus and sand and that allows the roots in the grass to get in there. And as you can see on the grass around the school, it’s taking off quite a bit. And so that’s what I do, you know? Also at the moment, we have got a bit of clay soil which is really hard to get grass to grow on it, and so I put some of this compost on it and after a while it just takes off. So this is where the magic happens *he indicates to the various stages of compost*
Us: So all of this is just grass?!
Roy: Yeah basically, although as you can see there are a couple of sticks and leaves and the leaves - they actually play a pretty important role because they provide potassium. Also the grass and branches and sticks are full of nitrogen. So you’ve got nitrogen and potassium and that’s just really good for the soil and then plant growth. So yeah that’s what I do.
Us: Have you ever come across any problems with the soil in the school?
Roy: Yeah, all around the school it’s the clay. With so many girls walking over it and packing it down, there’s just no accessing of the roots. Clay on it’s own has a lot of good nutrients in it but when it’s just so packed, you have to add compost to it. So that was the biggest problem when I first came here was a lot of the soil was just clay.
Us: Wow..yeah
Roy: So what’s this project that you’re doing?
Us: Well, we’re doing Yr 9 sustainability and we are taking action and stuff so we have been doing VSA’s - Visual Soil Assessments around the parks and so we are looking at different soil types and that sort of stuff.
Roy: Ah yeah well here I want the soil for the grass to be slightly acidic but Judy wants quite a lot of mellow soil so I’m putting in a bit of lime for her that she adds in to her gardens and so yeah.
Us: We were wondering whether we could do some VSA’s around the school?
Roy: What are VSA’s again?
Us: Well, it;s when we dig up a 20cm cube of soil and we look at the structure and the aggregates and we search for earthworms.
Roy: Yeah definitely! Would you do it in different area’s?
Us: Yeah, we would like to do it in places where there is clay soil and stuff
Roy: Excellent. Also there are a lot of areas like by the chapel where I have tended to the soil and so the soil you find there is quite different from the soil you’ll find like outside the Sport Centre. And then also take one from opposite the canteen area - by the big tree - that has quite good soil there too.
Us: Ok, thank you so much!
Roy: Yeah no worries hope it all goes well!
Raising Awareness
To raise awareness around Hamilton we created flyers to hand out to the public and to put in letterboxes and posters to put up around town. We created this website and also set up a Facebook page. We visited Horsham Downs Primary School and showed them around our website, informed them of the issue, completed Visual Soil Assessments with them and gave them puzzle sheets to complete.
Visiting the school
We visited Horsham Downs School and gave them a presentation about our inquiry. We explained our research, what we've done and how they can help. We then handed out a crossword puzzle at the end to test them on how much they remembered from our talk.
Preparing for the Gala
We set up our presentation for the gala by setting up a stall. On this, we displayed our poster and an information booklet containing our research. We also displayed this website and set out a soil sample from our VSA's