Differentiated forage management - system comparison at crop rotation level (Klee-Ass) 2022 - 2025

The year-round cultivation of fine-seeded legumes (e.g. red clover, alfalfa) is an essential pillar for the nitrogen cycle and soil fertility in both livestock and livestock-free organic farms. With the increase in livestock-less organic farms with a focus on arable crops and cash crops, the cultivation of fine-seeded legumes initially took a back seat. However, the realization is now gaining ground that the great advantages of clover-grass or alfalfa-grass cultivation make their cultivation indispensable for livestock-free organic farms. For conventional agriculture, cultivation is becoming increasingly important due to climate change and the demand to increase sustainable production with the integration of legumes. Livestock farms strive for both high N efficiency and high forage quality. However, there are reservations among farmers to decide to cultivate legumes due to the economic disadvantages that could result from one or two years of loss of the market crops that would otherwise be grown on the land. Therefore, the overall objective of the project is to optimize the cultivation methods of fine-seeded legumes with respect to establishment time, useful life and species composition. The project is based on the hypothesis that by optimizing the cultivation of fine-grain legumes, the on-farm nitrogen cycle can be improved and the monetary performance of crop rotations in organic and conventional farms can be increased.

Central to the project is the establishment of several exact trials under organic and conventional cultivation conditions, where sowing methods and times, the choice of species of mixture partners and cultivation duration are tested. The focus is on comparative studies with the deep-rooted drought stress-resistant alfalfa, and grass, white clover and ribwort are to be integrated as mixture partners. The main focus of the investigation will be the determination of the N2-fixing capacity, the stand development and forage quality of the legume stands, the yield effects on the subsequent crop and the effects on the economic performance for the farms. The project sets a new focus with the selected species spectrum specifically optimized for drought. For the first time, it combines the investigation of different sowing times, utilization periods and species spectra in an organic as well as in a conventional cultivation system with a well-founded plant cultivation evaluation using state-of-the-art methods, a detailed evaluation of the forage quality taking into account ruminal fermentation as well as an economic analysis specifically tailored to the operational situation of the organic or conventional farm.