EN
The objective of study conducted in 1994-97 was to determine white clover and birdsfoot trefoil, with perennial ryegrass and meadow fescue suitability for simple mixtures used on temporary grassland in Olsztyn Lakeland conditions and study of possibilities of considerably reduction and even elimination nitro gen fertilisation of legumes - grass mixtures. The results showed, that tested species showed high useful in simple mixtures in share of 50% grass + 50% legume plant enabled to obtain high yields without necessity of using nitrogen fertilisers. Legumes improved contents of total protein, crude fibre and Ca, also Mg and Na, K: (Ca+ Mg) and K: Na ratio, but more profitable chemical content characterised white clover.