Arthur Gray reports on interventions that have greatly improved the way pastures are managed, by enhancing the regrowth after grazing and spreading fertiliser more efficiently.
The first was the introduction of pasture topping. The machine that has proven to be the most successful over the years is the Fieldmulcher™, developed by Falcon more than twenty years ago. Burlington Farming, in the Cookhouse area of the Eastern Cape bought four 2,0 m cut width machines in 2005 and uses them to keep ahead of the area grazed daily by 1 900 dairy cows. This machine cuts the uneaten tussocks and pulverises and spreads the cowpats, thereby greatly improving the palatability of the new grass. Users also report that regular topping helps control weeds, especially in ryegrass and kikuyu pasture. A more recent development is the Flail Cutter, which can cope with pastures that have become overgrown.
The efficient use of expensive fertiliser is currently a major factor in producing milk from pastures at a profit. The adoption of precision farming methods has meant a breakthrough in reducing costs. Modern fertiliser spreaders are extremely accurate, with load cells and sensors that monitor the spread pattern to ensure accurate spreading of all kinds of fertiliser under varying operating conditions.
Fertiliser spreaders are now available with section control, which means that, in irregular or wedgeshaped fields, the spread pattern can be controlled, by means of a global positioning system (GPS), using an ISOBUS terminal. As the spreader crosses an area that has already been spread, that section of the spread pattern shuts down. This also applies to areas that fall outside the field boundaries, where the tractor and spreader approach the edge of the field. It means that fertiliser is evenly spread, just on the designated area, with no unnecessary overlapping or spreading outside the field boundaries, resulting in considerable cost saving.
The latest fertiliser spreaders can also work to a field map, prepared from grid soil samples, showing the required rate of application to correct the soil fertility for different areas of the field. Using a GPS, they can be set to automatically apply fertiliser at variable rates to different areas, as designated by the map, ensuring that no area of the field is overfertilised or underfertilised. This results in optimum use of the fertiliser and maximum returns.
The terminal controlling the spreader also records the spread rate and the amount of material spread, enabling accurate costing of the operation. These actions require no input from the operator other than the initial setting; everything is controlled by the computer in the display unit. However, the operator can override the instructions by using either the buttons on the controller or the touch screen. The latest innovation to improve the accuracy of the spread pattern is a device that measures the wind direction and strength and automatically adjusts the spread pattern to compensate for wind drift.