The American cranberry (Vaccinium macrocarpon Ait.) is a perspective and marketable crop both in Latvia and foreign markets, but berries are affected by rot in storage. The aim of the study was to detect the incidence level of cranberry fruit rot at the beginning of storage period in different places in Latvia. In 2007 - 2011, two hundred sound berries (out of 1000) were randomly collected by hand along a diagonal from five different cranberry plantations from locations all over Latvia. Berries were kept in plastic bags for a month and refrigerated at +7 °C. At the end of November, berries were sorted and rotten berries were separated from the sound ones. Over the period of 2007 - 2011, the incidence of storage rot reached 12 - 15% at the end of November, with an upwards trend observed every year, but the hot and rainy summer of 2010 significantly reduced the quality of fruit in storage, peaking on the average 33% of decayed berries. The incidence of fruit rot varied among the inspected cranberry plantations, but a tendency was observed that older plantations produced more rotting fruit and incidence of the disease was 12 - 50% after a month’s storage in the oldest plantation. The application of fungicides during the vegetation season did not affect development of post-harvest rot. Storage rot was a problem in the cranberry samples from all inspected plantations in Latvia, and in future the incidence of fruit rot is expected to increase.

Production of cereals is mostly processed by operating the machinery. Operation of machinery influences the yield, i.e. also the income on one side, but it is also one of the biggest sources of expenses from the other side. Increasing the yearly operation time and amount of work of the machinery leads to decreasing costs per unit. Increasing the yearly amount of work is limited by agrotechnical terms. The crop yield depends on the time and duration of field work, and affects the farm income. The methods and formulae to prognosticate the averageoptimum yearly operation time of farm's machinery, i.e. also farm's cereal-growing area was composed by the author, concerning biological, technical and economical factors and relations, affecting cereal production. Farm profit and profitability were used as optimization criteria.

The phenomenon of global climate change holds utmost importance in its impact on forest ecosystems. To mitigate the effects of this phenomenon, several European countries have introduced non-native tree species into their forests. However, comprehensive ecological analysis is needed to assess the suitability of these non-native species. Pinus strobus is often considered a potential substitute for native species. Tree-ring analysis is a useful methodology for evaluating the relationship between tree growth and meteorological conditions, given the significant impact of these conditions on tree development. In this study, 25 core samples were collected from an experimental plantation of Pinus strobus located in the western part of Latvia for analysis. The plasticity of the tree-ring width of Pinus strobus was evaluated using a multiple additive regression model. The analysis revealed that the previous summer precipitation was a significant factor, indicating the drought sensitivity of the increment. Additionally, the temperature in the previous July and August was also found to be a significant meteorological parameter, suggesting some tradeoffs between growth and the formation of nutrient reserves. The estimated growth responses suggest that the radial increment of Pinus strobus growing outside its native range is highly weather-sensitive, implying uncertainty in its growth with anticipated climatic changes. These findings emphasize the need for further ecological analysis to determine the suitability of non-native tree species and their ability to withstand the climatic changes.

The topic of this article is relevant because in Lithuania the assessment of the area occupied by plantations and green spaces has shown that the area standards do not meet the requirements and recommendations of the World Health Organization. Green spaces are regulated differently in different countries of the European Union. Lithuania has also developed a legal framework for the protection, management and establishment of new plantations and green spaces. However, this legal framework is improving and new laws are being added to it. Comparative, analytical, as well as statistical, and logical analysis methods were used for the investigation. The data of the Land Fund of the Republic of Lithuania for 2002–2022 were used for comparative investigation. The aim of this article is to perform an analysis of the change in the trees and shrubs greenery area of Lithuania in 2002–2022. In Lithuania, for example, trees and shrubs occupied 84,687.48 ha in 2002. In 2022, the plantation area amounted to 208,609.48 ha. From 2002 to 2022 the area of tree and shrub plantations in Lithuania increased by 123,922.00 ha or 146.33%. The analysis shows that in the period between the years 2002 and 2022 the biggest increase in the area of shrubs and plantations took place in Utena County (32,715.83 ha or 395.27%), but the smallest increase in Tauragė County (2,642.93 ha or 37.69%) and Marijampolė County (4,581.39 ha or 72.25%). The development of plantation areas has been positively influenced by the creation of an appropriate legislative framework and the implementation of plantation programs in counties and municipalities.