Part I : Reflection on research methods in organic grassland and animal production at the Louis Bolk Institute, The NetherlandsKey words: organic agriculture, anthroposophy, methodology, research strategy, experiential science, multidisciplinary science, Goethean scienceThis dissertation focuses on the research question: what is peculiar to agricultural research when its purpose is to support the conscious development of organic agriculture? What approaches, designs and methods are used for such research? Since the 1990s the Louis Bolk Institute has become one of the important actors (...) in the field of organic research and development. The author analysed the methodological aspects of seven case studies, each following the same format: background of the project, methods used, a reflection on the methods and, to a limited extent, agronomic results. Each of these sheds light on an aspect of the Louis Bolk Institute's approach to research.Organic farming is experienced as a new paradigm and its research methods need to do justice to it. Three criteria were formulated for this purpose: the self regulation of farming systems, the involvement of farmers and the respect for the integrity of life. Two conceptual frameworks are used to analyse the research methods: (1) a four-quadrant matrix. Epistemological, ontological and methodological changes in the way of thinking are relevant in discussions about holism versus reductionism and positivism versus constructivism. The second framework is (2) a triangle which can show the relationship between the underlying values, the involvement of the actors and the nature of the scientific process.The scientific position which is defended in this dissertation can ultimately best be described as a 'radical holistic research strategy'.Research approaches applied in the case studies are: interdisciplinary research, experiential science and mutual learning, farmer-to-farmer learning, exploring tacit knowledge, bio-ethical evaluation, Goethean science and systemic development. In the four quadrant matrix two new additional research methods are positioned: (1) Goethean science is included as a holistic counterpart to multidisciplinary system ecology; (2) experiential science is included for comparison with mono-disciplinary experimental research. The constructivist character of both Goethean science and experiential science particularly distinguishes these methods from mainstream science.The meta-reflection on the research showed some important new elements of research. There was a systemic orientation in terms of a cohesive set of management measures and actions. This systemic orientation also encompasses holism in terms of Goethean science. In addition there is the experiential science based on intuitive action and pattern recognition. The reflection on the methods made it clear that their acceptance was influenced by the underlying scientific philosophy.The entire research strategy is thus based on two different interpretations of knowledge. Experiential science focuses on the actions of the farmer and is based on the epistemology of action. In addition there is an epistemology of knowledge, where it relates to interdisciplinary research and Goethean science. There are barriers to the acceptance of these scientific methods in the current lack of suitable statistical evaluation methods, and also in the absence of accepted methods for explicitly exploring reality as constructed by people.Part II : Effects of manure types and white clover (Trifolium repens) cultivars on the productivity of grass-clover mixtures grown on a humid sandy soilKey words: organic agriculture, grass-clover, white clover cultivars, animal manure, potassium, nematodes, earthwormsThis Part describes the agronomic results of the multidisciplinary grassland study. This project concerned the effects of clover varieties and spring applications of animal manure on the yield of grass-white clover mixtures on a moist sandy soil (1993-1996). To be aware of the context of the findings in a multidisciplinary approach, attention was paid to: chemical soil fertility, damage to clover by slugs and soil borne nematodes. To increase the understanding of soil fertility, earthworm dynamics were also measured. At the end of the period the botanical composition of all plots was assessed. Factors measured besides total yield and clover yield were N, P and K yield. It was found that these 'context'- measurements were important for the overall explanation of the scientific results. Data were used for modelling several relationships between yield parameters. The overall findings of this project led to an understanding and description of the main aspects of manure with regard to grass-white clover growth on a moist sandy soil.It was concluded that on a moist sandy soil the amount of inorganic and organic N, the N release and the K input were the main manure factors relating to fluctuations in total yields on white clover development and on N yields in the first six years after sward establishment. The inorganic N component in manure can be used strategically to improve the growth of the herbage in spring. Maintenance of soil fertility in terms of P, K and Ca levels is an important key factor for a successful organic grass-clover sward.Carbon rich FYM derived from a deep litter stable and composted before application increased the earthworm population, reduced the number of nematodes and maintained the highest level of soil pH, all factors which might positively affect white clover growth in the long term. FYM applied in spring resulted in the typical extended growth season in the second part of the growing season. On a sandy soil the high concentration of K in the FYM positively affects the potential white clover growth.The choice of a persistent white clover cultivar is another important factor affecting herbage and N yields of an organic grass-clover sward. However, winter losses were not found to be the main cause of white clover reductions over the years. Losses in the growing season were related to slugs which reduced white clover leaf area. The literature shows that the cyanide concentration in DM herbage affects the susceptibility of white clover to pests. (shrink)