Assumption that forest reproductive material is better adapted to local conditions is the basis of current forest policy that promotes the use of local material. Genetic diversity and structure of two approved seed stands and three non-approved stands of Fraxinus excelsior L. were analysed with nuclear microsatellites to get genetically based support for the use of its reproductive material in Slovenia. Genetic diversity was high (H E = 0.80) and diff erentiation between populations measured as

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... F ST (F ST = 0.018) low to nonexistent when measured with genetic distances. Calculated al-lelic indices for seed stands were the same or a bit above the Slovenian average with two exceptions. Based on the analysis of fi ve microsatellite loci, no restrictions for transferring forest reproductive material within the studied range can be presented. However, collection of forest reproductive material from seed stand Rodik should follow good seed collection practices to ensure high genetic diversity of reproductive material.