An experiment was carried out to examine the forecrop value (weight of post-harvest residue and accumulation of total nitrogen, phosphorus and potassium) of spring wheat, spring triticale, field pea, and spring wheat-field pea and spring triticale-field pea mixtures in the respective proportions of 80 + 20% and 40 + 60%. An impact of these forecrops on winter wheat was determined. The field experiment was set up at the Experimental Farm in Zawady over 2001-2004. The soil was the rye very good complex. The largest and the smallest amounts of post-harvest residue were produced by spring triticale and field pea, respectively. The weight of post-harvest residue of the spring triticale-field pea mixture was significantly higher and the accumulation of total nitrogen, phosphorus and potassium was also higher than the accumulation by the post-harvest residues of spring wheat-field pea mixture. Winter wheat grain yield, yield structure components and grain total protein content were significantly impacted by weather conditions and forecrop. Field pea and spring wheat- and spring triticale-field pea mixtures more beneficially influenced the yield level of spring wheat than the cereals which were mixture components. An increased share of field pea in the spring wheat- and spring triticale-based mixtures from 20 to 60% significantly increased grain yield and total protein content in winter wheat grain. Choosing grain yield as an assessment criterion, field pea and the mixture of spring triticale and field pea in the respective proportions of 40 and 60% were found to be the best winter wheat forecrop under the soil and climatic conditions of central-eastern Poland.

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