The time within which, accordingly to its application, machine works, and an object of work and working groups are under load, is the effective active time. The purpose of the research was the order statistics of effective active time of limbing and conversion at chainsaw use. The removed trees were moderately diversified from the point of view of effective active time of limbing and conversion. The negative skewness coefficient qualified the distribution of effective active time of limbing and conversion as weak left-side asymmetry in variant 1 (the limbing included cutting of trees’ crowns and all branches). The positive skewness coefficient qualified the distribution of effective active time of limbing and conversion as weak right-side asymmetry in variant 2 (limbing included cutting of tree crowns and only thicker branches).

The paper presents the results of laboratory research on the effects of different soil compaction caused by varying unit pressure and its impact on germination and growth parameters of common beech. Soil for the research was taken from the forest stand, and then poured into prepared PVC cylinders. Pressure was exerted on the soil with use of the stamp, on a specially prepared static stand. Unit pressure ranged from 50 to 300 kPa with 50 kPa resolution. Each variant of the exerted unit pressure and control without pressure was repeated three times. 21 seeds of common beach were sown into a single cylinder. The cylinders were then placed in controlled conditions and after 2.5 months all seedlings parameters were measured. 234 seedlings were analysed (sown 441). It was found that the seeds were influenced by the place of sowing. There were significant correlations between the exerted unit pressure and the length of root system of plants sown away from direct exposure to the stamp, as well as all the plants together. With the increased unit pressure the length of root system decreased. Sowing place turned out to be important for the root neck diameter, root dry weight and whole plants.

The essence of conducting a forest nursery production is high quality planting material. Its essential element is rational fertilization of plants grown and conscious use of available methods and fertilizer application. Studies on the effects of fertilization on the growth of Norway spruce (Picea abies (L.) Karst.) can be used by foresters to properly choose the fertilizer needed to achieve the target of production. In the research foliar fertilization was applied, by the following means: “EM Naturally Active” (EM Naturalnie Aktywny – Greenland EM Technology) – liquid organic fertilizer with soil microorganisms, “Bioekor for conifers and ericaceous plants” (Bioekor dla iglaków i roślin wrzosowatych) – mineral foliar fertilizer in the form of a liquid concentrate trace elements and natural growth substances, “Ekolist standard” mineral foliar fertilizer in the form of a liquid concentrate. The study was conducted in 2009-2010 in the forest nursery situated in the Forest District Spychowo. Spruce seedlings transplanting was used. Experiments consisted of four objects repeated in four blocks. The fertilization was performed six times – 2009, and four – 2010. The measurements were performed three times. Annual growth of seedlings taken, from height of measurement was calculated. Analysis of the results obtained, did not show statistically significant differences for any of the applied methods of fertilization.

The paper presents an analysis of surveys conducted in companies using willow Salix Viminalis for energy production in the Podkarpacie province, it shows that companies are interested in the production of energy from biomass. The use of willow as a renewable energy source for the production of energy from biomass is a very good solution. The respondents claim that insufficient number of producers of willow, and thus, insufficient amounts of product delivered, is a barrier, inhibiting the development of their companies. To increase the amount of biomass purchased from farmers, the companies intend to encourage biomass producers to keep and expand existing plantations by awarding them permanent contracts to provide energy willow. All companies prefer biomass in the form of wood chips, but are aware of the lack of appropriate harvesting machinery and drying equipment. These factors affect the quality and price of wood chips, which is quite high from the viewpoint of manufacturers.