Digging/Spading strips to limit drought damage and wind erosion.
The weather in Australia can take extreme forms. In addition to long heat waves, massive forest fires, as we know them from 2019. The extreme drought and the wind erosion that results from this are a thorn in the side of Australian arable farmers. Because sometimes they see their yields literally go up in smoke. For this reason, Australian farmers and researchers are developing new methods to mitigate the effects of drought. One of these methods is digging. Alfons Sleiderink, director of Farmax, explains: “The weather forecast for the Netherlands is an extremely dry growing season. So let Dutch arable farmers take a look at the experiences they have gained in Australia. It is interesting to see how they deal with dry periods to secure their yield ”.
Research in South Australia
The agricultural university of South Australia contacted Farmax in 2015. The aim was to investigate the effect of spading on sandy soils in a dry climate. There are many Australian farmers who apply a layer of clay to their fields. This is mixed by the building furrow to increase retention. One of the innovations that is being tested in Australia is spading the strips. Due to the drought in Australia, sandy soils that are worked in full-field have a greater chance of wind erosion. They want to investigate this treatment with strips, improving the soil structure and limiting the effects of wind erosion. Digging strips is working the soil where the seed should be. Between the strips, the soil remains untreated with crop (residues) from the previous cultivation. Spading strips allow the bottom to be worked deeper than milling strips.
In 2019, the strips of spits in Wynarka (South Australia) were compared with other forms of soil cultivation. In this study, the following matters were concluded: a yield increase of 15% on the test plot could be achieved by combining strips of spits and sowing barley in one pass. The seed had direct access to the soil moisture. In the study, a comparison was made with a tilling operation where sowing took place 2 days later. Here the top 5 centimeters appeared to have dried out within 48 hours. The main explanation for the increase in yield was a higher bacterial count and less wind erosion during the spading strips.
Agricultural research to limit drought damage > Recent practical experiences in Australia:
- Arable farming in South Australia mainly takes place on sandy soils. Arable farmers have been applying clay and organic matter to their soil for several years. With a spading machine they mix this through the building furrow, so that the retention and soil fertility improves.
- South Australia’s agricultural university is researching new soil improvement techniques to combat the effects of drought. One of these methods is spading, which also includes spading strips. After positive experiences of Australian arable farmers they contacted Farmax. Since 2015, they have been carrying out field tests with a spading machine. Farmax has made the LRP Profi Trailed available for this.
- The research focuses on the mixing effect of the spading machine. Peak speeds and the design of the spade spades are central to this. A relationship has also been established between the mixing of organic matter and the effect on the soil conditions. There are also studies into strip cultivation.
- At a practice location in South Australia, the effect of different speeds on the mixing effect of crop residues in the soil has been compared. The results are mapped from the practical data using a simulation program. The conclusion is that peak speed does make a distinction between the mixing effect of soil residues in the soil:
– Up to the first ten centimeters, a higher peak speed mixes better than a lower one.
– From ten centimeters, a spading machine mixes better at a lower rush speed.
– This research uses organic dyes that are mixed during spading.
- An important aspect is the effect of spading on retention and soil fertility. Non-tillage tillage is widely used in Australia. During the investigation, chicken manure was applied to a sandy bottom and worked in with a spading machine. The soil was better able to retain the rainwater and deliver it to the plant in the first 400 mm by introducing organic matter. Integrated manure resulted in a direct yield increase of 600 kg during the investigation. In addition, there is of course a structural improvement in soil fertility in the longer term. The full-field action must be weighed up against the risk of wind erosion.
- The design of the Farmax shovel has been studied from a technical perspective. In addition to the current design, other spades have also been tested. The current shovel consists of 3 shovels per flange. New designs with 4 shovels, wider shovels or wider distance between the flanges on the spit rotor have been tested. The amount of torque the machine needs was checked on a light sandy bottom. This study showed that the current design requires between 10 and 30% less torque than other tested designs. This means that the current design has less soil resistance. The effects on fuel consumption have not yet been further analyzed.