GLYPHOSATE SUBSTITUTION
Written by Thomas Preuße, Chief Editor “DLG-Mitteilungen” and DLG-Agrifuture Magazine Forgoing glyphosate will increase the demands made on the cultivation system as a whole. It is vital to minimise the pressure caused by weeds overall. Replacing glyphosate with one single alternative measure is therefore barely conceivable, especially in systems that do not involve the use of ploughs. Wherever ploughing is not possible or desirable, greater importance will also (have to) be given to crop rotation and/or intercrops because of this.
Are Iron and Electricity the Answer If the curtain really does come down on using glyphosate at the end of 2023 in the EU we do not yet know if the UK will follow. However, it does not mean either the end of the world or necessarily a forced return to ploughing. But it will certainly make life more difficult for regenerative farmers. They will have to think more extensively in terms of 'the system' than 'the measure'. In the future, arable farming will not be led by the technology; instead, the technology will follow the arable farming objective. For a while, the situation surrounding the most controversial crop protection active substance of all time had settled down a little, but the date has been set. Glyphosate is only approved throughout the EU until the end of 2022, and that is next year. Even if the active substance were to be registered again at EU level and approved nationally, its use will either be restricted in terms of quantity and/or will only be possible in special cases: the product has long since had its heyday. At times, it accounted for 70% of the crop protection agent volumes used in Germany. Another reason why
glyphosate is so popular is that it can also be used to control volunteers such as grass weeds and rapeseed and not just rhizomatous weeds. Farmers may say 'If I can't use glyphosate, I'll just have to start ploughing again.' And many of them will do exactly that or are already doing so today. After all of their positive experiences, others don't want to see a plough on their land again at any price. Amongst others, Detlev Dölger and Wiebke Lenge of Hanse Agro, a private consulting company headquartered in Schleswig-Holstein, believe that both groups should rethink their stances. The standard for the technology must be the arable farming objective – and only this, not the existing technology. To determine this objective and therefore make the right decision, it is necessary to ask oneself several questions, whereby the question concerning grass weeds is at the very bottom of the list. • What are the demands of the subsequent crop; what time remains until sowing? • Does the soil have to be loosened? • What about the volume of straw and chop quality?
•H ow deep down is the germination moisture? Where is it (too) dry or (too) moist? • What must/can I do to control rhizomatous weeds, grasses, slugs, mice or cutworms? Winter rapeseed after winter cereal, for instance, is a classic case in which forgoing glyphosate may pose a problem. The time between harvesting and sowing is very short, and it is very tempting to use a plough before sowing. It couldn't be easier: the straw is ploughed under, grass weeds are buried and the soil is sufficiently loosened. No wonder that plough sales have picked up again, although some people had already consigned this implement to the 'scrap heap of history'. Boundary ploughing to control the influx of grasses is a widespread standard. But is it really necessary? If the location is dry, the straw can be easily worked in and sufficient time is available, there is nothing to suggest that tillage and cultivation cannot be undertaken without the use of a plough. Here, Hanse Agro recommends shallow cultivating (4 – 6 cm and 6 – 8 cm) twice to distribute and mix in the straw, then deep cultivating once and
Tools that work at very shallow depths are suitable as an alternative to glyphosate, particularly where black grass is concerned. Photo: Väderstad
76 DIRECT DRILLER MAGAZINE
ISSUE 13 | APRIL 2021
