Strip roads serve to enable silviculture operations, maintain biodiversity, and decrease damages to the soil and environment. At the same time, strip roads decrease the productive area. The aim of this study is to evaluate the influence of strip roads on the productivity of spruce plantations growing in different density regimes. Five trials, each of 0.234 ha area, with different density regimes and two replications in an experimental spruce plantation were used for this study. The permanent plots were established in the plantation of 15 years of age and were remeasured every 4–5 years over 24 years. Differences in tree growth between outer rows bordering strip roads and inner rows, 1.75 and 3.5 m from the strip road, were estimated using t statistics. The gross annual increment of trees in outer rows at age 39 years exceeded the increment of trees in inner rows by up to 60%–78%. Increase of productivity occurred primarily due to the more intensive diameter growth and higher density of trees in the outer rows. In general, the influence of strip roads on the total productivity of plantation depends on the ratio of the growth intensity of trees between outer and inner rows as well as ratio of the width of treed strips to the width of the strip road.

Background and Objectives: Significant progress in developing European national forest inventory (NFI) systems could ensure accurate evaluations of gross annual increment (GAI) and its components by employing direct measurements. However, the use of NFI data is insufficient for increasing the efficiency of forest management and the use of wood, as well as for meeting sustainable forestry needs. Specification of forest characteristics, such as GAI and its components, identification of the main factors that impact forest growth, accumulation of wood, and natural losses are among the key elements promoting the productivity of forest stands and possibilities of rational use of wood in large forest areas. The aims of this research were (a) to validate the quality of forest statistics provided by a standwise forest inventory (SFI) and (b) to reveal the potential benefits of rational wood use at the country level through the analysis of forest management results, which are based on GAI, including its components derived from the NFI. Materials and Methods: SFI and NFI data from 1998–2017 were collected from 5600 permanent sample plots and used to evaluate the main forest characteristics. Potential wood use was estimated based on the assumption that 50–70% of the total GAI is accumulated for final forest use. Results: Mean growing stock volume (GSV) is underestimated by 7–14% on average in the course of SFI. Therefore, continuous monitoring of the yield changes in forest stands, detection of factors negatively affecting yield and its accumulation, and regulation of these processes by silviculture measures could increase potential forest use in Lithuania. Conclusions: Implementation of sample-based NFI resulted in an improvement of forest characteristics and led to an increase in GSV and GAI. Continuously gathered data on GAI and its components are a prerequisite for efficient forest management and control of the use of wood.