Father and son Dirk and Frik van Sittert live on the neighbouring farms Paardeplaats and Leeufontein some 18km from Hartbeesfontein in North West. Collectively they farm 1 000ha of their own and hired land, of which 500ha is devoted to crop production and 500ha to grazing. Normally they plant maize for two seasons and sunflower in the third, but depending on the prospects for each crop, this may be changed. They have a herd of 120 Angus-Bonsmara cross cows and Angus bulls for the production of weaners, and a small flock of some 80 sheep.
The role of coincidence
Dirk and Frik started applying no-till practices some five years ago following a series of coincidences. They had recently purchased a farm to increase their arable hectares, in order to justify their intended purchase of new conventional tillage machinery to replace their ageing equipment. However, they found that the newly acquired land was overgrown with couch grass (kweek), which required the application of glyphosate herbicides and minimum disturbance.
At the same time they received a visit from Johannes Smith, an agronomist from Omnia based in Hartbeesfontein. He told them what he had learned about no-till during a study tour across Australia with Chris Roode of Lichtenburg and a party of other local farmers. The tour visited regions with conditions similar to those in North West (see Farmer’s Weekly, 20 July). Johannes said that all they needed was a decent spray unit and a reliable tractor. He added that besides the benefits of the conservation agriculture (CA) principles of minimal soil disturbance and coverage, no-tilling would reduce their machinery, capital and operating costs while causing minimum disturbance to the couch grass.
“At first we considered this utter nonsense,” says Frik. “However, as I had studied soil structures for my BSc Agric at the University of the Free State, Johannes’s observations gave me food for thought and we started to give no-till serious consideration. Additionally, Johannes took us on visits to other farmers practising no-till to find out if we were on the right track. Among them was Chris Roode who had started successfully no-tilling in Lichtenburg two years ago and who gave us the benefit of his experience – that’s when I changed my mind! Frankly, most farmers do not understand the dynamics of soil and what leads to its structural change. If they did, they would more readily convert from conventional to no-till practices.”
Taking the plunge into no-till
With assistance from Johannes, Dirk and Frik began by ripping their lands with a Rovic & Leers Super 18 spring-loaded ripper to a depth of 450cm with tines set 450cm apart to break the compaction. They then had their soils analysed by Omnia, who recommended the application of lime. They applied and mechanically incorporated dolomitic lime, as was normal practice for the area, and sprayed glyphosate as a pre-emergence herbicide. The Van Sitterts no-till planted sunflowers with their conventional John Deere planter, placing weights on the seed bins to gain penetration. They also manufactured a sprayer with baffle plates to apply the glyphosate herbicide without affecting the sunflower plants. The result was an excellent crop which proved to them that no-till worked and they need not plough.
“The second year we adopted soil-balancing practices and changed to calcitic lime. Also, having established that there was no compaction where the sunflower rows had been planted and to minimise root disease transmission, we planted subsequent crops between the previous rows in straddle fashion. This is similar to the method used in Brazil, where they plant diagonally across the previous crop, but we cannot do this due to terrain and contour restrictions. We have not ripped our lands for five years and there is no evidence of any compaction,” says Dirk.
Dirk and Frik maintain that the cavities left by the previous crop’s root systems result in more rapid rainfall infiltration to significant depths while also transporting the lime into the soil. As a result they now spread the lime on the soil surface instead of mechanically incorporating it. This, together with the crop residue, which is increasing every year, reduces water runoff and soil erosion. “Before we started no-till the mud washed off our land was so bad that our vehicles got bogged down. We recently had 100mm of rain and all that happened was that some of the maize stubble was lodged in our fences. The runoff that did occur was clear of any soil,” comments Frik.
Changes to equipment and planting
As the conventional John Deere planter had uneven seed placements, in their third season Frik purchased a Brazilian Jumil 2980 PD Exacta eight-row no-till planter which gave them precise seed placement. Dirk eventually settled on a six-row. “We plant maize at a rate of 18 000 plants/ha and sunflowers at 36 000 plants/ha in 90cm rows, and obtain yields averaging between 3t/ha and 4t/ha. However, this coming season we are going to plant maize at 15 000 plants/ha because of the reduced soil moisture after this year’s drought conditions and because some of the new varieties deliver two cobs per plant.”
Significant cost savings
“On average our yields have increased by about 0,5t/ha, but I would argue that even if we got 0,5t/ha less than average it would still be economically viable at normal grain prices because of the reduced input costs achieved with no-till.
For example, diesel consumption for the entire crop-production cycle including delivery to the local silos has decreased from 60ℓ/ ha to 20ℓ/ha. Indeed, some farmers using conventional tillage may even use between 80ℓ/ha and 100ℓ/ha,” says Dirk. Additional cost reductions have been achieved with Frik’s 142kW New Holland TM 190. It took only 300 hours to initially plant 380ha and replant 200ha, resulting in less servicing and maintenance and a longer replacement period.
Seeing as they no longer plough and till they have reduced their smaller-kilowatt tractor fleet from six to two, which do a minimum number of hours a year for tasks such as hauling fertiliser. As a result, they require fewer tractor operators and farmworkers and no longer need to purchase plough shares at R70 apiece for each furrow, which in sandy soil needs replacing daily.
On the flipside, Dirk and Frik maintain that no-till requires far more management than does conventional tillage. They also point out that there are few advisory services available; not much research is being done in South Africa on CA, of which no-till is one element; farmers who have the infrastructure required for conventional tillage are loath to change; and some farmers prefer to keep on doing what their forefathers did. They believe these are the reasons why CA and no-till are not practised to a far greater extent on the Highveld.
Contact Frik van Sittert on
083 400 3314 or e-mail [email protected] |fw