New locations of Persian walnut (Juglans regia L.) in valleys of selected right-bank tributaries of the Warta River in Poznan, part 3

Krzysztof Janku, Mostefa Mana, Ewa Arczynska-Chudy


Studies on the occurrence of Persian walnut (Juglans regia L.) in the valleys of the analysed watercourses confirmed that this species grows along all of the tributaries of the Warta River within the Poznan city limits. The specimens were most commonly found in lines of trees (267 pcs) and in forests. Total number of observed trees reached 348 pieces. Authors suppose that it is significant that no specimens of Juglans regia were found next to the Czapnica watercourse bed, but 1 7 pcs were recorded on the slopes and along the shoreline ofCzapnica Lake. The distribution pattern of the species could be associated with the presence of gardens in the vicinity of the lake. Entering forest associations by this species (74 pcs) is new and very different from previous studies in this area. The recorded diameters at the breast height (DBH) of trees growing next to Główna and Cybina watercourses indicate the ongoing expansion of walnut in the valleys of these watercourses.

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Persian walnut, river valleys, urban area

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Forestry Letters  eISSN 2450-4920

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