Hurricanes, high temperatures and drought have caused damage to forests in the Żywiec Beskids. The effect of extreme weather events on the population of Ips typographus was examined in the damaged spruce stands in the period of 2005-2007, using pheromone traps for catching beetles. The daily average number of trapped beetles in a single pheromone trap ranged between 32 and 72 in subsequent growing seasons. It was proved that thermal conditions at different altitudes affected the beginning and the course of I. typographus swarming. Three swarming peaks were observed in each of three consecutive growing seasons. Extremely high temperatures in 2006 did not increase the number of swarming peaks. In 2007 the number of beetles in pheromone traps was twice higher than in the first year of the study.

There were formulated two general approaches to the problem under consideration indicating the experimental data sources. Mathematical symbols were introduced to denote each plant part and describe its function. There was constructed a discrete two – dimensional dynamical system that depicted Scots pine growth process followed by making suitable assumptions on its components. It has been found that this system is an iteration sequence of certain area transformation which served as the basis for the dynamical system development. Consequently, several important results like theorems, comments and charts were obtained. The obtained research results are related to variations of total dry weight M_n that grows exponentially, while linearly for n large enough. It was also demonstrated that the proportion of assimilatory to non assimilatory parts λ tends to the calculated stationary point λ₁ .

Various activities are undertaken worldwide in order to counteract the visible climate changes. One of them is promotion of renewable energy sources. Aims established by the European Commission with respect to increasing the share of energy obtained from RES assume an average increase of up to 20% by the year 2020. Poland, as an EU member state has been obliged to increase the share of energy from RES to 15%. Promoting renewable energy sources contributes to diversification of supplies, thus providing conditions for the development of energetics at a local level. Taking into account Polish conditionings it is believed that biomass, including forest biomass, can be an important renewable energy source. The present study focuses on the problem of efficiency of energy wood chip production from forest biomass utilizing a Bandit 2090 wood chipper. Chipping efficiency, depending on the condition of particular tree stands, ranged from 14 to 17 m³·h^-1.

The basic purpose of this study was to determine a working-day structure and work productivity rate during the process of timber harvesting in mountain conditions. The parameters were determined on the ground of data collected during field studies. The aforesaid working-day structure was defined on the ground of time study observations. The areas included in the survey were typically mountain stands, in which cutting was applied by means of a cutting method IVd. Work teams assigned approximately 50-70% of their work-shift time to technological operations, whose greatest part was taken by delimbing and slashing. A significant portion of the day was taken by preparation of a workstand (approx. 10%), as well as cutting and felling. This was caused primarily by the necessity of snow coat removal. Technological work productivity rates amounted to some 3 to 14 m³ per day per one worker. During the skidding process, a significant percentage of trees remaining along the skidding path was being injured. On the ground of the obtained results and their analyses, an attempt was made to evaluate and suggest possible changes in timber harvesting organization, in order to improve work productivity rates.

This article presents new technological and technical solutions for forest nursery, which were developed recently in Department of Forestry Mechanization at Agricultural University in Krakow and implemented in forest nursery. Fertilizer dispensers equipped with mechanism to mix, loosen, and initial soil thickening were made, in order to enrich the ground with mycorrhizal fungi, fertilization and presowing preparation of soil. Thick seeds spot seeding section of Agricola Italiana type PK seeder was modified in order to use in spot seeding, so now it can sow thick seeds like beech or fir and tiny seeds in double rows which make it a universal seeder to sowing forest trees seeds. Sections, up to 5, mounted on construction can spot sow seed perches in field conditions. In order to use in corridor, sowing field seeder arm was modified by extending it, so it was possible to mount sideways seeding units and tractor can be driven next to corridor. Electrical tool holder was constructed for spot seeding under cover, to which you can mount equipment for soil preparation (sowing fertilizer, mycorrhizal biopreparate dosage, loosing and rolling ground), spot seeder sowing sections or constructed saddle for performing weeding.

Civilizational development requires seeking for more and more modern methods of satisfying growing needs of the society. Living standards grow together with economic growth and, as a result, demand for energy grows as well. This fact is tantamount with the necessity to look for alternative energy sources. Otherwise, our civilization will soon have to face degradation of natural environment and shortage of conventional energy resources. Under Polish conditions, crucial role in utilizing renewable energy is played by biomass, and its importance is going to grow over the years. The present study has assessed productivity of three willow clones: Tur, Ekotur and Turbo, grown in short rotations on farmland.

In Poland, the demand and availability of high efficiency machines such as harvesters and forwarders has been increasing in the last decade. On the one hand, forestry needs technologies safe for the environment, soil, water, and people. On the other hand, Polish forestry investors and service companies are constantly buying both new and second-hand harvesters and forwarders. The main aim of this paper was to determine the actual number of machines currently used in Poland. The secondary objective was to describe the ownership structure of these machines. Information on the number of forest machines is very important for economic reasons. The Key Performance Indicator (KPI) informs us “where we are” and what tendency and trends we may expect. The number of forest machines needs to be monitored on a regular basis.

Costs are the most important indicators of profitability in any business activity. The forest logistics chain consists of wood, the supplier, the buyer and the producer. Costs arising from the use and operation of forest machines such as forwarders and harvesters should not be forgotten here. The aim of this study was to define and describe all elements of costs. In such an analysis conducted for the most popular machines, costs were assessed in terms of fixed and variable costs. The purpose was to estimate the degree to which the total cost structure is influenced by servicing costs and spare parts costs. Innovation of this study is connected with the collection of actual accounting data.