Size and vitality characteristics of bilberry (Vaccinium myrtillus L.) populations in the Central Bohemian region of the Czech Republic: A case study of non-timber forest products

Bilberry (Vaccinium myrtillus L.) is a key non-timber forest product that plays an important role in forest biodiversity and ecosystem function. This study evaluated the vitality levels of eight bilberry populations in the Central Bohemian region of the Czech Republic, examining whether their vitality depends on the habitat type. Morphometric analyses were conducted, measuring 13 static metric and 16 static allometric morphological parameters of bilberry shoots. Statistical methods, including correlation, factor analysis, and ANOVA, were employed to determine the vitality index and population vitality structure based on the algorithm developed by Y.A. Zlobin. The results indicated that bilberry plants exhibit significant morphological variability based on forest conditions, forming plants with specific habitus traits. High positive correlations were found between many morphological characteristics, which were grouped into five clusters, each comprising 2–4 parameters. Among these, phytomass, total leaf surface area, and plant height were identified as the key determinants of vitality levels. Bilberry populations in Central Bohemian forests were classified into three vitality categories: prosperous, balanced, and depressed. The study found that the most vigorous populations, with Q-index values between 0.3333 and 0.4375, were located in associations such as Pinetum (sylvestris) vaccinio (myrtilli)-oxalidosum (acetosellae) , Pinetum (sylvestris) vaccinio (myrtilli) , and Pineto (sylvestris)-Piceetum (abietis) vaccinio (myrtilli)-oxalidosum (acetosellae) . These populations are also of high economic value due to their bioresource potential. The study underscores the importance of habitat type in influencing bilberry vitality and offers insights into future research on bilberry populations as a vital component of non-timber forest products.