We've got 20 odd hectares here. It's a pretty typical dune swale system which is typical of the Mallee. So, on the top of a dune, which is basically windblown. Aeolian is the scientific term. Windblown sands built up over many, many, many thousands of years. And in the swales, which is the bit between the two dunes, the soil is heavier. The first thing we did here was to conduct a fairly extensive soil survey. By soil survey we used an EM38 which is an electromagnetic means of assessing major textual changes in the soil. Then, on the basis of that information, we then went back and dug soil pits, which is the normal way of doing things. So, a 75 metre grid, and we then assessed the sort of profile all the way down for its texture. And from that we can then make an estimate of the readily available water that can be held in the root zone. And the roots zone is probably more or less defined by the presence of a calcium carbonate layer. Calcites is the more scientific term for that, which generally represents the bottom where the roots will explore. So, on the top of the dune, that's down point eight of a metre to one metre, but in the swale it's far shallower, could be 400mm. And, as a result of that, and as a result of the soil texture changes, we know that the swale soils will only hold about twenty nine millimetres of water, readily available water that plant can extract. But up on the top of the dune, it's much, much higher, to the order of forty nine (mm) or something. So, we know then from that, that the way we lay our trials out will need to take that into account. What it means of course is that the trees in the swale will need to be irrigated differently to the trees on the top of the dune. The trees in the top the dune probably won't need to be watered as much or as often. But the trees in the swale will need to be watered more frequently, because they will pump out water, the available water far more quickly. What we're trying to do though is, we're not interested in irrigation per say. We're interested in identifying what the true signal is from whatever it is we're doing, in the case of the planting, the first painting we've made is the true signal to the root stock and to the amount of nitrogen we're putting on. In the case of the higher density plantings, it's again the true signal to the root stock, also to the scion. That's what we're trying to identify. We don't want any of our results to be affected by under or over watering. If they're over watered, they get wet feet and that generally makes them unhappy. If you're underwater, of course it's going to restrict growth and we've got the wrong signal, that's not what we want. That's not what we're after. Now our next development, which is more or less where we are standing now, we'll be testing the effect of root stock. And, as I mentioned the dune and the swale hold different amounts of readily available water. Now as we move from the top of a dune down into the swale, and into the subsequent dune, you know there's a whole stack of things in there about, as I said, under and over watering. It's going to be a logistical nightmare to be able to control, to properly control the water to all those numbers of plots in there. It's expensive, from a scientific viewpoint it's expensive, but it is a good industry outcome in the sense that what we come up with at the end of it, will be meaningful and not swayed by, or we won't have picked up a wrong signal due to under or over a watering. We are out there though on the edge of what irrigation technology can currently offer. But, in the future, I think we'll be moving closer to the point where there will be autonomous irrigation systems on very, very small plots. In some senses, what we're trying to do here is a bit of a forerunner to that, because we'll be able to demonstrate that there might well be a need, and that need could potentially be driven very much by both the soil we're on, but also what we put on it. When we're planting dwarfing root stocks, and with whatever on top, they will fill out the space available, slowly or quickly, depending on what's there, whether what we've planted. That will have an impact on how much water is being pumped out. Once we go into the future, you can see the day when irrigation blocks will become smaller, because water is not becoming more available, quite the contrary. As we move to that situation, then the degree of control will have to be far finer than we currently do, and in many ways, establish orchards, a dune and a swale would be treated more or less the same. We know that, and they did that for, that's done for all sorts of reasons, legitimate. But we know that that's probably not going to be the appropriate thing in the future for those developments that are coming in 10 15 years hence.
We are growing a mixture of cereals, like rye-corn and oats. We grew them because, we grew those two, because we want to maintain the soil. We get strong winds and their soil will move. That's the basis of the formation, of the land for the land form we see here. In any case, we we've got to make sure that soil stays here. So, we grew those two, the cereals, because well they make good growth, for a start. They have a composition that means that they will break down reasonably slowly in summer. Remembering that our soils of warm, they may get wet and dry reasonably frequently, which tends to promote the decomposition of whatever plant materials lying on top. The outs and the rye corn have a composition that sort of slows that down. It also helps us suppress summer weeds, which imposes a cost on us. Because the history of the site there's probably, for all intensive purposes, an inexhaustible supply of spiny weed seeds. Californian puncture weed and so forth. We need to be able to suppress that. We need to suppress that, economics. It takes time for people to spray that out, and we don't want to be applying, if we can help it, we don't to be applying weedicides too frequently because, the hazardous chemicals for a start. There’s all those sorts of considerations for the operator. There is also consideration for the environment. We just don't want to be using herbicides or having to use herbicides excessively. Suppressing those weeds with just a layer of plant trash, which is essentially what we're producing here, helps us suppress that, helps us suppress germination and their growth.
