Emerald Ash Borer (EAB), Agrilus planipennis, is a beetle that originates from East Asia. Upon invasion to North America in the early 2000s, it killed untold millions of ash trees. In European Russia, EAB was first detected in Moscow in 2003 and proved to have the potential to also kill native European ash (Fraxinus excelsior). The beetle has since spread in all geographic directions, establishing itself in eastern Ukraine by 2019 and possessing potential for further westward spread towards the EU. Apart from the approaching EAB, F. excelsior is currently threatened by the dieback disease (ADB) caused by the invasive ascomycete fungus Hymenoscyphus fraxineus. The infestation by EAB combined with ADB infection is expected to be more lethal than either of them alone, yet the potential consequences are unknown. To date, eastern Ukraine represents the geographic area in which both invasions overlap, thus providing the opportunity for related investigations. The aims of the study were to investigate: (i) the EAB expansion range in Ukraine, (ii) the relative susceptibility of F. excelsior and American ash (Fraxinus pennsylvanica) to EAB and ADB, and (iii) the combined effect/impact on ash condition imposed by both the pest and disease in the area subjected to the invasion. The results have demonstrated that (i) the invasion of EAB is currently expanding both in terms of newly infested trees and invaded geographic area; (ii) F. excelsior is more resistant to EAB than F. pennsylvanica, while F. excelsior is more susceptible to ADB than F. pennsylvanica; and (iii) the infection by ADB is likely to predispose F. excelsior to the infestation by EAB. It was concluded that inventory and mapping of surviving F. excelsior, affected by both ADB and EAB, is necessary to acquire genetic resources for the work on strategic, long-term restoration of F. excelsior in devastated areas, thereby tackling a possible invasion of EAB to the EU.

The Emerald ash borer (EAB), Agrilus planipennis Fairmaire, 1888 (Coleoptera: Buprestidae), an invasive phloem-boring beetle, was first detected in the Luhansk Region of Ukraine in 2019. Subsequently, it rapidly expanded its presence to encompass a significant portion of the Kharkiv region and the parks of Kyiv. Previous research has established that the climatic conditions in Luhansk and its neighboring regions are conducive to the EAB, and the absence of a host plant (Fraxinus sp.) does not act as a deterrent to the pest’s expansion in Ukraine. Recognizing the urgency of identifying infested trees, our current research aimed to identify the most attractive EAB forest subcompartments based on forest site conditions and stand structure. Utilizing the MaxEnt model, we achieved an average performance in predicting the potential distribution of the EAB (AUC = 0.842). The six most impactful variables, contributing to 88.2% of the model, include “age of trees, years”, “area of forest subcompartment, ha”, “mean height of trees, m”, “proportion of Fraxinus excelsior in the stand composition, %”, “hygrotope index (humidity level), point”, and “number of neighboring-non-forest subcompartments”. Most likely, EAB occurrence is expected in the driest forest site conditions; the well-lit and warmed-up parts of stands, in particular; small subcompartments surrounded by non-forest landscapes; and forest shelter belts near roads and fields. However, the data obtained can be considered preliminary. To enhance the accuracy of our forecasting, it may be imperative to consider data on road localization, along which the pest can spread passively, as well as dominant wind speed.

Досліджено основні переваги та проблеми екосистемних послуг, які надають полезахисні лісові смуги (ПЛС). Здійснено економічну оцінку екосистемних функцій ПЛС за двома групами послуг: забезпечення; регулювання та обслуговування. За попередньою еколого-економічною оцінкою, в Україні вартість корисних функцій, які надають ПЛС, становить 39,8 млрд грн / рік. Частка послуг забезпечення становить 0,3%, послуг регулювання та обслуговування – 99,7%. Встановлено, що вартість матеріальних ресурсів ПЛС становить близько 117,3 млн грн/рік. За умови впровадження сучасних економічно-рентабельних практик створення ПЛС, вартість матеріальних ресурсів потенційно можна збільшити на 60-70%. Вартість кисню, що виділяють ПЛС, оцінена за гуртовими цінами і становить 16,7 млрд грн/рік. Внаслідок впливу ПЛС, збільшення вартості сільськогосподарської продукції щорічно становить близько 17,3 млрд грн/рік. Компенсаційні механізми запровадження заходів зі створення та утримання полезахисних лісових смуг можуть містити прямі державні виплати та податкові стимули, а також прямі приватні виплати. Схеми оплати таких заходів можуть містити компенсацію вартості поглинутого вуглекислого газу, зниження податкового навантаження, пільгове кредитування проєктів створення та реконструкції ПЛС, які охоплюють використання рослин-медоносів або лікарських рослин, відшкодування вартості садивного матеріалу тощо.

Poplars (Populus spp.) are of significant ecological and economic importance. Long-term breeding efforts were aimed mainly at obtaining fast-growing and productive plants and less considered resistance to pests. This study aimed to identify patterns of susceptibility or resistance to Saperda carcharias (Linnaeus, 1758) (Coleoptera: Cerambycidae) infestation among clones of Populus hybrids and pure species, focusing on the influence of their placement, seasonal development, stem diameter, height increment, and crossing combinations. Among 34 clones of poplar species and hybrids of Ukrainian and foreign selection, in 2019–2023 S. carcharias infested 14 clones every year. Six clones (‘Ivantiivska’, ‘Kytaiska × pyramidalna’, ‘Volosystoplidna’, ‘Novoberlinska-3’, ‘Robusta’, and ‘Lada’) were the most susceptible to the infestation by S. carcharias. The clones of all presented poplar sections and their crossing combinations, except the Tacamahaca and Leucoides cross, were infested. Greater height increment promoted the infestation by S. carcharias. Ambiguous results were obtained regarding the susceptibility of Populus hybrids compared to pure species to S. carcharias infestations. Considering infestation by S. carcharias and plant placement in the site, it can be concluded that the clones ‘Sakrau45-51’, ‘Deltopodibna’, ‘Rosijska’, ‘Slava Ukrayiny’, ‘Lubenska’, ‘Rohanska’, and ‘Nocturne’ are resistant to this pest. Selecting native species clones or creating mixed clone plantations could enhance the resilience of poplar plantations to pest threats.

The wide ecological range of Scots pine ( Pinus sylvestris L.) demonstrates its ability to adapt to different environments. This study aimed to assess the dynamics of growth and productivity of Scots pine stands growing on soils with crystalline parent rock outcrops. The study area is located in the north of Ukraine in the Central Polissya within 50°15’ and 50°06’ north latitudes and 29°22’ and 29°86’ east longitudes. The base of the geological structure is granite. The depth of the parent rock bedding ranges from 15 to 86 cm. In total, 18 research plots were laid out on soils with crystalline rock outcrops and 18 research plots on sites with deep bedding of crystalline rocks (> 60 cm). To test the difference in stands growth within and outside sites with the crystalline outcrops, we used the Welch t-test. Pine forests on areas with deep bedding of parent rocks are systematically higher than those growing on sites with crystalline outcrops. With an increase of stand age, the difference between specified groups tends to be more significant. Stands growing on sites with and without crystalline rocks outcrops have similar dynamics, however, the latter ones accumulate more growing stock volume due to higher relative stocking, site index, mean diameter, and the number of trees. Our findings indicate the feasibility of establishing Scots pine stands in sites with different depths of the crystalline parent rocks bedding in Central Polissya, Ukraine.

We analysed the quantity and quality of Quercus robur L. acorns after years with a very poor yield under the canopy of natural oak stands of various compositions, ages and stock densities in the northeastern part of Ukraine. We determined the mass of 1,000 healthy and damaged acorns of the current year. The levels of variability were estimated for the number and mass of acorns under the canopy of the studied stands. The dependences of the number of acorns on the age of oak stands and their stock density were studied. The total number of acorns under the canopy of natural oak stands was 9,900–19,000 seeds per hectare with a total mass of 26.8–54.1 kg per hectare in 2020 and 8,600–17,200 seeds per hectare with a total mass of 22.7–48.4 kg per hectare in 2021. The proportion of damaged acorns was about 70% both in 2020 and 2021. The largest number of acorns was concentrated under healthy trees (without signs of decline) that had a well-developed crown and, therefore, received more sunlight and heat. The identified quantitative and qualitative estimates and acorn spreading pattern need to be considered when selecting sites for further natural seed regeneration in old-aged oak stands.