Effective management of blackgrass in cereal crops hinges on a deep understanding of the weed’s biology and employing efficient stubble management techniques.
Blackgrass In Cereals
Blackgrass is a type of weed commonly found in cereal crops. It’s problematic because it competes with crops for resources like nutrients, light, and water. This competition can significantly reduce crop yields. Blackgrass is also known for its rapid growth and high seed production, which makes it challenging to control once established.
Its resilience and ability to thrive in various conditions, including wet environments, add to the difficulty in managing it effectively. As a result, blackgrass can cause substantial economic losses for farmers and requires careful management strategies to control its spread and impact.
Strategies To Beat Blackgrass
Dr. Louise Cooke, a research scientist with ADAS, emphasizes the importance of using stale seed beds to control blackgrass outbreaks. This method involves allowing blackgrass seeds to germinate before eliminating them with glyphosate.
ADAS, renowned as the UK’s premier independent agricultural and environmental consultancy, offers extensive policy advice and research and development services.
At the Teagasc Grass Weed conference in 2023, Cooke highlighted the critical decision farmers face in blackgrass management: whether to let the weed seeds germinate or bury them.
She pointed out the crucial role of crop rotation in blackgrass control. This strategy enables the use of various herbicides and different sowing dates, reducing weed emergence. A key element in managing blackgrass is cultivating a competitive crop, ensuring it is sown under optimal conditions to prevent weed proliferation.
Pre-Harvest Blackgrass Management
Cooke advocates for addressing blackgrass before harvest, noting that about 80% of these weeds emerge in autumn. This timing is the weed’s primary vulnerability. Annually, there’s a 70% reduction in seed viability, suggesting the potential to eradicate the issue from the seed bank within five years.
Blackgrass seeds cannot sprout from deep within the soil, so deep burial can prevent their growth. However, the weed’s strengths lie in its high seed production and ability to thrive in wet conditions.
Cultural control methods in autumn can yield inconsistent results, and while ploughing is an effective strategy, it comes with high costs. Once blackgrass numbers are substantially reduced, there’s an improved efficacy of selective herbicides, according to Cooke.