Organic farmers have shown an increasing interest in growing herbs in their pastures because they potentially can have health benefits, positive influence on the milk and the milk yield, and contribute to the variety and ‘naturalness’ of the pasture, among others by offering the cows a variety of different tastes and additional micro minerals and other substances.
At a workshop for Danish organic dairy farmers which took place in June 2012 as a part of the SOLIDproject, several farmers discussed the need for collecting long term experiences with using herbs on pastures. There was especially focus on the survival of herbs in long-term pastures because it was a wish to prolong the number of years between ploughing with the aim of reducing CO2 emission (related to machinery) and building up carbon deposition in the soil. See below their responses…
What motivated the farmers to start using herbs?
Half of the farmers started using herbs 14-18 years ago when they converted into organic production. As far as they remember their decision about using herbs was not influenced by advisors; they just wanted to offer their animals a more varied feed with different tastes. Some farmers had noticed that their cows preferred to eat trees and wild species of herbs if offered, rather than the grass which was available in the field in abundance. Other farmers emphasised that mineral supplementation was a reason because they perceive especially herbs with deep root systems like chicory to draw up minerals from deeper soil-layers. A third reason given by farmers was the expectations of medical effects of using herbs e.g. against parasites and against ruminant bloat/ tympanitis.
Farmers make their own experiments with herb mixtures
The famers who started using herbs on own initiative 14-18 years ago have over years tried different compositions of herbs. One herb which has been used continuously is Chicory (Cichorium intybus). This herb normally establishes quit well in the field, the cows like it, it is believed to have a medical effect on parasites and on ruminant bloat and to have a high mineral content. Herbs like dill and parsley have been tried but given up again. Dill had a poor re-growth after harvest or grazing and parsley germinated very slowly, lost competition with other herbs, and never really established in the field. These very experienced herb-farmers continue to develop their methods and experiment with different mixtures. That is also the case for the two farmers who took part in the research projects by Karen Soegaard in 2007. In this specific project, seven different herb-species chicory (Cichorium intybus), ribwort plantain (Plantago lanceolata), caraway (Carum carvi), salad burnet (Sanguisorba minor), birdsfoot trefoil (Lotus corniculatus), chervil (Anthriscus cerefolium) and sainfoin (Onobrychis viciifolia) were sown. These two farmers both continued using herbs in all pastures, although just one (chicory) or a few species are used now.
Farmers use what is currently on the market
The herbs currently chosen by the farmers seem to reflect which herb-seed mixtures which are available on the market. Most farmers use these mixtures which include herbs like chicory, Sainfoin, ribwort plantain, caraway, dill (Anethum graveolens), birdsfoot trefoil and salad burnet. The farmers however know that some of the species often establish very poorly in their pastures, and if they had the possibility they would have adjusted the balance of herb species in the mixture. Some farmers add other herbs to these mixtures like alsike clover (Trifolium hybridum) while others choose just to add chicory seeds to the traditional grass-clover seed mixtures.
Farmers’ experience that some herbs are better ‘survivors’ than others
Farmers had experiences with some herbs surviving better than others. Herbs like chicory, caraway, Lucerne, red clover and ribwort plantain are relatively large plants with deep roots and they both have a high competitiveness the year the pasture is established, and they are also the best survivors in a long term- perspective. Herbs like Lucerne and ribwort plantain seem better suited for cutting than for grazing and chicory and caraway seem to be the only plants able to survive grazing over several years. However, in general, farmers told that all sown herbs had difficulties surviving the winters, their occurrence were markedly reduced every year and barely existing after 3-4 years. Farmers also experienced that in very dry periods, herbs coped better with drought than grass. Especially deep rooted herbs like chicory, lucerne and alsike clover had a remarkable drought resistance. Several farmers experimented with keeping their herb/grass pastures for more and more years before ploughing. The oldest pasture was 6 years old.
Sowing herbs broadly versus in stripes
Almost all interviewed farmers used herbs in all of their grass-fields, both fields used for grazing and for silage production. They either buy seed mixtures including herbs or they mix herb seeds with grass and clover seeds before sowing and in that way the herbs are broadcasted all over the fields.
Only one farmer was sowing the herbs in 30 cm broad stripes for every 4th meter. He had observed that in this way the survival of the herbs was increased because the competitive pressure from grasses and clover was decreased. Most other farmers considered also to try herb-stripes in the pastures to increase the competitiveness.
Herb fields were not used for hay, but silage production worked well
The herb fields were normally never used for hay production because the dry leaves crumble away if they are handled more than once. Only one farmer had made hay one time on a field dominated by lucerne and in a period with stable sun and warm weather. Silage production seems to work well except in one of the pure herb fields without grass. Here the leaves from chicory fall to the bare soil when cut, and when they dry they get sticky and difficult to pick up without soil. In this way the silage quality is markedly reduced due to soil contamination. In the other pure-herb field a cover of low grasses (poa annua) had established from the seed bank in the soil, and in this field there were no problems with soil contamination because the chicory leaves were carried up by the grass cover.
The cows enjoyed eating herbs
All farmers reported that their cows were happy to eat both fresh herbs when grazing (except the old tough stems of chicory) and silage made from herb-grass fields. Only the silage including sticky chicory and soil was disliked by the cows. Some farmers had the impression that especially in the springtime the cows preferred herbs and leaves from bushes and trees in hedgerows before grass. The farmer who established bands of herbs on the pasture described how the animals could stand in rows grazing primarily these stripes of herbs.
Farmers perceived herbs as contributing to good animal health
The farmers were asked whether they had noticed any effect from use of herbs on the health of their cows. Since there had not really been a before-after situation for many years, they were not able to see any difference. They all stated that they generally perceived their cows to be very healthy.
Cows which had taken part in the herb-silage project only got the pure herb-silage for 3-4 weeks, which was not enough to observe any difference on their health. Several farmers were convinced that the herbs contributed to the mineral supply of the cows. One interviewed farmer had not given other supplementary minerals to the cows the last six years – and had not experienced any negative effects. One farmer had many years ago a high prevalence of ruminant bloat in his herd. He solved that problem by exchanging red clover by alsike clover and adding caraway to the herb-seed mixture. In general the believed health-related effects on the cows and the fact that the cows seemed to enjoy the herbs were the main reason for the farmers to continue sowing herbs in the grass fields.