With the trend in agriculture to more extensive systems of production it is likely that less productive grasslands with lower inputs of fertilizer nitrogen will be used. However, there is a need to marry conservation orientated policies with profitable farming. It is therefore necessary to study the nutritional quality of forage from extensive pastures which will be used for animal production. The objectives of this experiment were to measure the digestibility in vivo of silages made from extensive pastures containing grasses, clovers, wildflowers and herbs and to investigate the feeding value of big bale silage from these pastures for feeding dairy heifer replacements for calving at two years of age.