How can varieties contribute towards integrated black-grass management?
The Leamington Spa Monitor Farm meeting yesterday had some challenging questions about identifying varieties which may help in the management of black-grass. Coming to this subject with little experience meant I learnt more than the audience on the challenges black-grass poses, but it allows me to look at the variety data in a different light.
Choice of variety will change depending on performance at different drilling dates. The RL wheat data shows yields of Reflection are 11.4 t/ha with September sowing, 10.9 t/ha October, 10.3 t/ha November. Moving towards the spring, KWS Alderon yields 10 t/ha in November and 7.7 t/ha in March drillings. If barley is your option, the hybrid barley Volume achieves 10 t/ha in the autumn, whilst the spring barley variety RGT Planet 8 t/ha in the spring. These yields are achieved in the luxury of black-grass free sites.
Designing a variety which will outcompete black-grass is a tall order. Do you need rapid tillering in all weathers and sow dates? Upright leaves? Large flag leaves? Tall crops? All alongside the normal requirements from a variety with quality, yield, standing ability and disease resistance. Of these characteristics, we do measure straw height in the RL but we need to look at this alongside straw strength.
It made me think that we don’t measure tillering performance in the RL or speed of crop cover. If we can get a steer from the researchers and agronomists as to their ideal black-grass competitive cereal crop, we could start to plan to do some additional measurements, or look at aerial ways to monitor speed of crop development which may in a very small way contribute to managing this problem.