PROTECTION OF PINUS SYLVESTRIS L. STANDS FROM CURCULIONIDAE DAMAGE

Abstract

One of the long-term goals of the certification systems (FSC (Forest Stewardship Council) and PEFC (Program for the Endorsement of Forest Certification)) of sustainably managed forests that provide both social, environmental, and economic benefits is to completely phase out the use of chemical pesticides to protect planting material. It is in the interest of both nurseries and forest owners to find successful alternative, environmentally friendly solutions to safeguard pine saplings against Curculionidae. The studied two-year-old pine stands are located in the Hylocomiosa forest type with a total area of 4.27 ha. In 2016 clear-cutting was carried out, and in the spring of 2018, containerized seedlings were planted in areas with partial soil scarification in three repetitions in each area. Six plots with three variants in each of the repetitions were prepared. The work aims to evaluate the effectiveness of the use of P.sylvestris protection against damage Curculionidae while comparing untreated (control) lots with the ones treated with the systemic insecticide Actara or wax based on the number of damages and growth of seedlings. The intensity of tree damage and the incidence of damage over two years, depending on the type of seedling treatment, was assessed, and the average tree heights were measured and compared. With an increase in the incidence of weevil damage, the intensity of damage is also observed. At the same time, a significant (p>0.05) difference in lesions between the types of treatment of seedlings has not been established. Within two years, the death of trees due to weevil damage is insignificant - 2 % of all seedlings treated with the systemic insecticide Actara, 5 % of seedlings treated with wax Kvaae, and 6 % of untreated seedlings or control. The treatment of seedlings significantly affected their growth in the first and second years after planting (p less than 0.05). The use of wax Kvaae resulted in higher costs and similar protection effectiveness as the use of chemical means.