Interaction of multispecies sward composition and harvesting management on herbage yield and quality from establishment phase to the subsequent crop

Abstract

Abstract Delayed harvest during different periods of the year may help to increase the multifunctionality in terms of simultaneous flowering resource and forage provision of ley grassland. Interaction effects of harvesting regime and the grass sward composition on herbage yield and quality were therefore investigated in two multispecies swards in the present study (a simple sward with five vs. a complex sward with 16 sown species) that lasted from the establishment phase (2017) over two main production years (2018 and 2019) until the subsequent cropping phase (2020) where legacy effects were analysed by growing annual ryegrass (Lolium multiflorum gaudini). A particular drought in the year 2018 affected the botanical composition which resulted in a lucerne‐dominated complex sward and a grass‐rich simple sward thwarting the initial aims of studying complex sward treatments. Extended regrowth in early summer increased herbage yield significantly while herbage quality, weighted over the respective periods, was hardly affected by harvesting regime. No consequence of the harvesting regime resulted during the subsequent cropping phase where the plots previously grown to the lucerne‐dominated complex sward resulted in significantly greater herbage dry‐matter yield, nitrogen yield and lower weed biomass. Overall, the interaction between harvesting management and grass sward composition was never significant. It is concluded that no negative consequence for herbage quality results at extended regrowth during part of the year. However, further studies comparing complex with simple multispecies swards should consider different soil types under more humid climate.