The aim of the study was to compare the growth parameters and the indicators of seedlings' breeding usefulness assessment depending on their quality class, which was determined on the basis of the requirements of the Polish standard PN-R-67025 (1999). The research material consisted of European beech seedlings grown in controlled conditions, which were divided into three quality classes ("class I", "class II", and "classless"). The seed lings belonging to individual classes differed

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... y in their growth parameters, with the exception of the length of the root system, and the highest values were characteristic of quality class I. The breeding usefulness assessment indicators did not fully confirm this rule. The average value of the Dickson quality index (DQI) indicated that class I seedlings would be the most suitable for planting, but for the sturdiness quotient (SQ) no significant difference was obtained, and the classless seedlings had the best root-shoot ratio (S/R). The obtained results indicate that some classless seedlings can be used for planting in a forest plantation despite the failure to meet the minimum values of growth traits contained in the PN-R-67025 standard used by the State Forests. Our research also suggests that in the assessment of the quality of planting material, as an element complementing the dimensional classification, we can include indicators of breeding suitability (SQ, S/R, and DQI).