Evaluation of the degree of healthiness of the pedunculate oak (Quercus robur L.) acorns in the Włoszczowa– Jędrzejów Nature Park and its neighbouring area

Abstract The aim of the study was to demonstrate the degree of healthiness of the pedunculate oak (Quercus robur) acorns found in the Włoszczowa-Jędrzejów Nature Park (abbreviation: W-JOChK) and in the neighbouring area. It was dealt with by making the analysis of health of the acorns (total 3,600). The research material included the samples of fallen down acorns, collected under the pedunculate oaks in Kurzelów (W-JOChK), as well as Żelisławice. The study was conducted from late September 2014 to early October 2015. The analysis of acorns demonstrated that over 50% of the acorns were damaged by insects. The ‘perpetrators’ of the damage proved to be Curculio glandium (Coleoptera: Curculionidae - acorn weevil) and Cydia splendana (Lepidoptera: Tortricidae - chestnut tortrix). It was stated that acorns from the pedunculate oak trees, which were found on the protected area, were twice less frequently inhabited by Curculio glandium than those originating from the trees in Żelisławice - near the industrial firm. The damages caused by Cydia splendana in both study sites were similar in number. The results indicate that the acorns of oaks in more polluted environment are probably more vulnerable to infestation by insects.