FARMVIEW Season 2 Episode 3.6
Episode 3.6 - Trialling salt bush in mid rows
Brown Brothers, Mystic Park
In conjunction with Chris Penfold from the University of South Australia, we have been trialling some salt bush here in some head-end rows. We just wanted to see if we can find a better way to manage our in-row, something that is more suited to the natural environment and something that will hopefully make the management of the vineyard a bit easier.
It is very well suited to the local environment so it should thrive here. It is naturally endemic to the area and it volunteers across most of the vineyard. It has definitely saved us on weed control. The salt bush acts as a natural weed mat and it keeps the weed growth down, so that has been very effective so far. Hopefully it will save us on chemical weed control costs and physical weed control costs like slashing.
The salt bush fits in with overall Brown Brothers Ethos. We are trying to manage the vineyard holistically, it is a native species so it is good for the environment, it is good for native insects, it is good for weed control and it does not need much help. It just gets along on the natural rainfall and does well in any quality soil. It volunteers just about anywhere and where we have sown it, it has done exceptionally well. We are just hoping that it makes our life a bit easier.
The potential benefits I think of growing the natives between the vines and here talking again mostly about salt bush, enhancing bio-diversity, for instance, improving soil health and improving economic returns to the goals as well. Natives are much better suited to survive, they have evolved over 1000's of years. The costs involved in establishing salt bush are reasonable. I think what we have to consider is that we are going at perennial species and as a perennial our costs can be amortised over many years. We still do not really know just how long it is going to last, within the vineyard, but we expect a minimum of five years, but I would like to say 10 and possibly even more than that and they produce a huge amount of seeds of their own accord and is self regenerating anyway, but overall over about five years I recon an annual cost of something like $250/hectare to get salt bush into your vineyards. As we see here I think we can really reduce that as well, because the fruit is a fantastic food source for the ants and so the ants are coming on, they are harvesting that and they are taking and spreading it around the vineyard themselves so we can probably come back to sowing probably every third row, or so, so that brings it back to divide it into a third again. So it becomes a very cost effective mechanism, if you look at over a longer term.
Salt bush can certainly assist in other areas of vineyard operation, I believe, because we can cut back on our management costs with them. Once we have a good established stand, it competes very favourably with many of our summer growing weeds. We have a look around here, we have got a cow drop for instance which is just an obnoxious weed, it is a horrible thing and the rivalling in Sunraysia is full of it and if we had to try and control it, it is an annual cost which is substantial in herbicides to do so. We do not want to tool the land, so it all becomes back to herbicides and that does add up in expense, whereas with this we are using a biological weed control mechanism that smothers out the cow drop, competed more than favourably with it and we just do not see it and it does not get looking. So from that perspective it really does work extremely well.
Some of the other benefits which we are finding with salt bush are we find an incredible increase in earth worm numbers where salt bush is growing. This plant has the capacity to produce a fair amount of bio-mass and all of that ends up in leaf fall back onto the ground, which then becomes food source for not only the macro- invertebrates such as earthworms, but also many of the micro invertebrates as well and so they are coming to the surface and go for their source of food and packing it down into the soil and improving soil structure and infiltration rates and so on all in the process.
I guess that the really nice things about the growing of salt bush between the vines as being the success that we have had in several sites, but it is not always that easy to establish, I mean it has not worked fantastically everywhere. Where it does establish well it is a lovely plant it is a good thick mat of desirable species and out competing the cow drop it just being a lovely little benefit that we have seen from it, but also there is other benefits that have come through particularly in the light of increasing our beneficial invertebrate numbers is being really nice to see as well.
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