Short rotation forests (SRF) can be used for biomass production for energy applications in Latvia. Establishment of plantations could be one of possibilities how to reach targets of renewable energy resource (RES) consumption of 40% in 2020. In Latvia’s conditions, one of most suitable species that could be used for SRF is willow (Salix sp.). Abandoned agricultural lands are suitable for establishment of plantations. Productivity of 8 oven- dried tons (ODT) ha-1 year -1 can lead to Rate of Return (IRR) of 17.1% and Net Present Value (NPV) 1099 Latvian Lats (LVL) if the biomass price is 33 LVL ODT-1. Establishment, harvesting and transporting costs account for 88% of the total cost of production. Price of wood chip and fuel plays the most important role in economics of plantation.

It is essential to have information on the tree biomass due to the fact that it is an important ecosystem pool for reporting changes in carbon stocks of forests and increased attempts to diversify the energy sources. In Latvia, comparatively few studies have focused on this topic so far. Our study was conducted on two 36 - 38 years old Norway spruce plantations. Detailed stem analysis of 39 trees was performed, and biomass of the above-ground tree components was determined. We analyzed tree and clone-level biomass distribution, biomass relations with tree dimensions and dependence on the genetic factors. The mean total biomass (kg d.w.) of all analyzed sample trees was 131.4 ± 10.58 kg, the mean biomass of stem 85.9 ± 6.98 kg, the mean biomass of dead branches 8.3 ± 0.82 kg, the mean biomass of living branches 23.5 ± 2.34 kg and the mean biomass of needles 13.7 ± 1.22 kg. On average, 66.1% of biomass was allocated to the stem, 6.4% to the dead branches, 17.4% to the living branches and 10.1% to the needles. The biomass of the analyzed trees positively correlated with all tested tree parameters - DBH, tree height, stem volume. Typically, with increasing tree parameters total biomass and stem biomass increased rapidly but branch and needle biomass increased slowly. Significant differences of tree dimensions were detected between the clones, and the differences in total biomass and stem biomass were clearly correlated with the differences in tree dimensions over clones. No significant impact of the clone was found specifically on the tree biomass or its distribution.

The paper covers analysis of pre-commercial thinning performed in private forests over the period of 2007–2017. Since 2007, permanent and considerable European Union subsidies for pre-commercial thinning have been available; resulting in a significant increase in area of thinned young stands in private forests. The aim of this research is ascertain pre-commercial thinning activity depending on the type of forest owner (individuals, legal persons or local municipality), forest stand type (forest stand or plantation) and origin (natural or artificial) as well as the forest owner’s intention to apply for European Union subsidies. Data analysed were obtained from Forest State Register – national data base, managed by state authority State Forest Service and continued analysis comprise two main topics – ascertain amount and type of young stands owned by different type of private forest owners and amount and type of conducted pre-commercial thinning. In comparison with other type of forest owners, legal persons have significantly higher amount (47%) of young plantation forest and forest stands from the total forest stands area. The highest intensity of thinning was conducted in plantation forests of artificial origin owned by legal and physical persons, also forest stands with artificial origin owned by physical persons. The current period for European Union Rural development programme will be over in 2020; therefore, it is important to analyse the existing approach of granting subsidies to forestry and find the improvement necessary for the planning period from the year 2021.

Main factors raised interest about biomass as the source of energy increase renewable resource demand in the context of Green house gases emissions decrease and the problem of environmentally friendly and efficient waste utilization. Legislation of waste water sewage sludge use is becoming stricter now. After cutting away top peat layer of peat quarry, the owners have two alternatives: the first, to flood the fields and transform them into bogs, the second, to carry out some economic activities - one of which must be field afforestation with traditional or fast growing tree species. Before planting trees it is necessary to fertilize the fields, and waste water sewage sludge will be one of potential fertilizers. Aims of research were to determine the impact of waste water sewage sludge fertilization 10 t haE-1 on tree growth and soil properties. Concentration changes of N, P, K, and Ca, Mg in different depth and concentration of S and total C and heavy metal in soil top layer during the year 2006 were determined. The effect of fertilization on tree growth and stock was determined by the non-destructive method, data were calculated by height and root core diameter of trees. Fertilization stimulates tree growth as weed growth too. On peat areas observed soil acidity decreasing. Despite of sufficient amount of nutrients willows were not suitable for peat fields. To avoid increasing of heavy metals content in soils, only qualitative waste water sewage sludge or waste water sewage sludge composts is acceptable for fertilization.

Turkey is a mountainous country with many high mountains. Recent estimations show that there are approximately 20.7 million ha of forested area in Turkey, covering 25.8% of the total land area. However, little over half of this forested area is classified as unproductive (51.7%). Artvin is located in the North Eastern Black Sea part of Turkey and is the home of a very rich biological diversity. Forests in Artvin region are in different climatic zones - from temperate climate to continental climate zone - and there are several vegetation zones in the region which ranges from sea level to the altitude of 3500 m. A Scotch pine (Pinus sylvestris L.) plantation, planted in 1996 in the alpine zone in Artvin-Ardanuc region, was investigated. The size of study area was 40 ha and this research was done on 12 sample plots. There were 50 Scotch pine seedlings on each sample plot. Height and root collar diameter of the seedlings were measured. The mean slope was the same (60%) on the sample plots, and the effects of exposure and altitude significantly affected the height and root collar diameter growth of the seedlings (P is less than 0.05). It was determined that increased altitude is associated with decreased height growth and root collar diameter of the seedlings.

More than 17,5% of Latvian agricultural land is abondoned, therefore effective use of this land is a significant issue in national economics. One of the alternatives of how to use abandoned agricultural land is its afforestation by birch. The present research is based on the Scandinavian experience. Calculations have been made on the necessary investments and management costs. The recovery and possible impact on price changes in raw birch materials are analysed as well.