Drought-Resistant pasture leys

Background and Objective

Grass clover leys are essential for organic farming, promoting weed control and crop health in subsequent crops and enhancing nitrogen fixation by legumes, thereby increasing following crop yields. Grass clover also serves as feed for ruminants, typically harvested mechanically and ensiled - a weather-sensitive, energy-intensive, and loss-prone process. Arable farms often have limited utilization options, with inefficient mulching being common. Grazing grass clover leys on arable land offers an efficient and cost-effective use of the herbage mass.

However, grazing comes with challenges in terms of management, trampling damage, and especially the continuity and quality of forage, particularly during dry periods. Increasing periods of spring and summer drought, driven by climate change, can rapidly reduce growth in short, frequently defoliated swards, making grazing more difficult as it depends on continuous growth. A potential solution is establishing drought-resistant and grazing-adapted grasses and forage herbs to enhance drought resilience and promote continuous growth.

The project aims to quantify the yield development of mixed grass clover swards with drought-resistant grasses and forage herbs throughout the year compared to conventional grass clover swards (e.g., perennial ryegrass and red/white clover). Interactions with optimized timing and method of establishment of the swards in the crop rotation will be investigated together with the research group Agronomy in the project KLEO.

The findings could increase the attractiveness of grazing grass clover leys in practice and support the development of innovative, efficient, and environmentally friendly production systems.

Approach

In a multi-year field trial we will compare different grass clover mixtures. Conventional grass clover swards (perennial ryegrass and red/white clover) will be compared with swards containing resilient grass species (cocksfoot, tall fescue, festulolium) and forage herbs (ribwort plantain, forage chicory). The composition of the additional species groups is modular, allowing the effects of individual and combined species groups to be examined. Yield development, forage quality of the entire swards, and yield proportions of individual mixture partners will be analysed. Frequent mowing will simulate grazing.

Our Research Questions

• How does the seasonal yield distribution and forage quality of grass clover swards develop when additional species groups are used?
• Can the use of resilient grass species and forage herbs in grass clover stands improve forage continuity during dry periods compared to conventional mixtures of perennial ryegrass and red/white clover without negatively affecting forage quality?
• What effects do the establishment of resilient grass species (cocksfoot, festulolium, tall fescue) and forage herbs (forage chicory, ribwort plantain) have on annual yield development?