Leys with high plant biodiversity as feed resources for pollinators

Summary

Multispecies leys contain different ecosystem services, and feed resources for pollinators can possibly be one. The challenge is to construct grassland with different flowering species and with a continuous flowering without compromising yield and herbage quality. A field experiment was carried out to examine the effect of cutting strategy in different designed species mixtures on yield, herbage quality and flowering. Two main types of mixtures were examined. High productive grass/clover mixtures with chicory, ribwort plantain or caraway and lower productive two species mixtures with weak competitors, salad burnet or dandelion, together with either birdsfoot trefoil, red clover or lucerne. The annual dry matter yield was not affected by the cutting strategy. The yield level in the two species mixtures was on average 33 % lower than grass/clover mixtures. Birdsfoot trefoil had a low production especially in second year in the two-species mixtures, whereas red clover had a high. The flowering was in general lower in first harvest year than in second, which could both be due to age and weather conditions. However, when combining the three cutting strategy there was, especially in the second year, flowering species during most of the growing season.
Thus, the experiment showed that combining the seed mixtures and cutting strategy could give a continuous flowering. Further research could improve knowledge about management of weak species and the potential for pollinators in such systems.