Warsaw, Poland
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Mederski P.S.,Katedra Uzytkowania Lasu | Karaszewski Z.,Zaklad Badania i Zastosowan Drewna | Rosinska M.,Katedra Uzytkowania Lasu | Bembenek M.,Katedra Uzytkowania Lasu
Sylwan | Year: 2016

In recent years, rapid changes related to forest operations have been observed in the forestry sector in Poland. A growing number of harvesters, an increased volume of harvested timber and a larger proportion of broadleaved species are considered the most important. The objective of this paper was to recognise the dynamics of harvester fleet change in Poland. In particular, there was an emphasis on finding out: 1) the total number of harvesters currently used in Poland (with respect to regions), 2) where and what type of machines were bought, and 3) which main factors influence the occurrence of these machines. In January 2014, a survey was sent to all forest districts. Questions related to harvesters and relevant for this paper included information about: 1) the number of harvesters in use, 2) the serial number of each harvester, 3) place of purchase (within the country or abroad), 4) status of the machine when bought (new or used), and 5) the forest district, in which an open tender was won for 2014. To avoid double counting the same harvester working in two or more forest districts, the serial number of each machine was used for identification. There were 368 harvesters reported in the survey in early 2014, although at the end of 2015 this number rose to 530 machines. The Central-West, North-West and North of Poland had the highest number of harvesters. Most of the harvesters were bought as used, though there may be a growing trend towards the purchase of new machines. A strong correlation was observed between the number of machines used in a region and the total area of lowland coniferous sites and forests, as well as the volume of harvested merchantable softwood. Currently, private forests and broadleaved species are the main factors limiting the application of harvesters in Poland.


Karaszcwski Z.,Instytut Tcchnologii Drewna | Lacka A.,Katedra Mctod Matematycznych i Statystycznych | Bcmbcnck M.,Katedra Uzytkowania Lasu | Mcdcrskl P.S.,Katedra Uzytkowania Lasu
Sylwan | Year: 2016

The delimbing and bucking of timber using a harvester head is very productive in comparison with a chainsaw operations, however it can cause damage to the outer layer of round wood. This damage can originate from the delimbing knives or from the feed roller spikes. As a consequence, grey fungi can develop on coniferous species, and faster wood drying is also observed (with no regard to the species). Feed roller spikes create cuts and dents on the outer layers of the wood. When plywood is processed, the cuts and dents are recognised as damage as a consequence, they lower the wood quality and value. The objective of the presented research was to find out: 1) the depth of cuts, 2) the potential loss of volume, and 3) product value loss due to damage to plywood caused by feed roller spikes. The research was carried out on alder (Alnusglutinosa Geartn.) plywood logs harvested by a Valmet 911.4 with a 360.2 head. Measurements were taken using an electronic calliper with an accuracy of 0.01 mm. 16 plywood logs were considered, on which 384 measurement points (depth of spike cuts) were selected on different areas along the length of the log: 1, 2, 3 and 4 m from the butt end. The maximum depth of the spike cut was observed on the bottom part of the logs (1 m from the butt end) and amounted to 3.9 mm. This damage depth was statistically different to those at the 2nd, 3rd and 4th metre points, amounting to 1.9,1.9 and 2.1 mm, respectively. The biggest volume losses were on the lsl metre of the plywood assortments: 0.004 m3 (4% of the volume), while on the further parts (2nd, 3rd and 4th metres) only 0.002 m3 of the plywood had damage (2% of the volume). In addition, the highest product value loss was on the butt end logs and amounted to 302 PLN/€72 per 100 m3. The following plywood assortments (2nd, 3rd and 4th metres) had a loss of 76 PLN/€18 per 100 m3. Therefore, when plywood assortments are processed using a Valmet 911.4 harvester with a 360.2 head, it is recommended that after cutting and felling a tree, the plywood section of the alder tree trunk is cut off without feeding it through the harvester head.


Uczak L.M.,Zespol Skladnic Lasow Panstwowych w Stargardzie Szczecinskim | Jakubowicz P.-P.,Katedra Uzytkowania Lasu
Sylwan | Year: 2013

Paper evaluates the conditions that affect the functioning of the timber market and its role in the development of forestry and timber industry during the ninety-year-history of the State Forests. Four periods were distinguished, which, according to the authors, correspond to the key stages of development of the Polish State: the interwar period (1918-1938), the period of the Second World War (1939-1945), the post-war period (1946-1989) and the period after the change of the political system in Poland (1990-2008). Data concerning both forestry and the timber industry in these periods were collected, processed and compared to the general conditions of functioning of the Polish state.


The results presented in the article are a part of the research project on the variation in pure density of pine material in Poland. The aim of this work was to examine the variability in pure density of Scots pine wood along the trunk height depending on the type of the forest site, age range and geographic area of forest stand. The tests were carried out in four forest regions of Poland: Knyszyn, llawa, Tuchola and Zielona Góra. One model tree was cut down in each region, in live forest stands, in site of fresh forest of II, III, IV and V age range and fresh mixed forest of III age range. Twenty trees were collected in this way. The samples in a torm of wood slices were taken from tree trunks, every one meter. After being debarked and roughly polished, the3-4 cm high samples were used to determine pure density of wood in the intire trunk cross section. It was found that the pure density tested along the total trunk length ol model trees in all the regions, torest site types and age ranges was strongly correlated with a position on the trunk. Along with the growing height, the pure density was decreasing. In over 50% of cases lower wood density was found at saw cut than at the height of one meter. I was found that the pure density grows with age. In Knyszyn, Itawa and Tuchola in the III age range in the site ol Iresh forest, the pure density ol Scots pine wood reached higher values than in fresh mixed torest, excluding Zielona Góra forest, where the tendency was reverse.


Paper presents analysis of differences in conventional wood density of Scots pine measured at breast height regarding the geographical location of stands, forest habitat type, stand age and associated parameters such as density in the mid-length of the stem, density in the upper end of the stem and diameter at breast height. To investigate the impact of these factors, an analysis of covariance was used in accordance with two models specifically developed for this purpose. We found dependence of conventional wood density on the type of forest habitat and geographical location of the stand. The highest density was detected in dry coniferous forests, while the smallest in fresh mixed coniferous forests. Scots pine wood from Zielona Góra Forest (western Poland) characterised with the highest density, while from the Knyszyn Primeval Forest (eastern Poland)-with the lowest.


Poplawska D.,Zespol Panstwowych Ogolnoksztalcacych Szkol Muzycznych I i II st. nr 3 im. Grazyny Bacewicz | Lachowicz H.,Katedra Uzytkowania Lasu
Sylwan | Year: 2014

The article describes twelve recorders excavated from archaeological sites dating back to the Mediaeval times and the Renaissance. Three of them are in the museums in Germany, two in the Netherlands and one in Estonia. Six are in Polish museum collections. The flutes from five locations (Puck, Nysa, Płock, Toruń and Warsaw) are described in this paper for the first time. All the instruments from the Polish territory have been accurately measured and identified for the kind of wood from which they were made. All the flutes were made from one piece of wood of the following tree genera: lilac (Nysa, Płock), plum (Dordrecht, Göttingen), cherry (Würzburg), maple (Elblag, Toruń, Tartu), boxwood (Esslingen, Amsterdam) and spruce (Puck, Warsaw). The oldest known recorders were primarily made of fruit tree wood (Würzburg, Dordrecht, Göttingen). Interesting was the use of spruce wood (softwood) for making aerophones, absent in the later preserved instruments of this type.


Variation of wood strength coefficients was determined for the silver birch trees coming from north-eastern Poland which is the main source of raw material of this species. Samples were taken for measurement from twelve sample plots with trees at the age of 45 and 70 years growing in the fresh forest habitat. Strength coefficients were subjected to statistical analysis for compression parallel to grain, static bending, tensile strength parallel to grain and the modulus of elasticity in static bending. The research confirmed a significant effect of the location and age of trees on the mean values of coefficients of compression strength and modulus of elasticity in static bending. Moreover, a significant influence of location on the mean values of coefficients of tensile strengrh parallel ro grain and static bending strength without the effect of tree age on these coefficients was found. Also a simultaneous influence of the location and age of trees on the mean values of all studied coefficients was demonstrated.


Paper presents the methodological assumptions of assessment of the attractiveness of the forest landscape in the vicinity of the municipal road Kup - Radomierowice (SW Poland). Landscape attractiveness was determined by the means of diversity of landscape units expressed by quotient of the sum of structural and stand units and the length of the landscape unit. The results allow determining the possibilities of landscape formation along the roads. Decisions about shaping of the road vicinity should be based not on the assessing the visual attractiveness of the landscape, but rather on detailed analysis of scenic variables and especially spatial relationships that occur among them.


Moskalik T.,Katedra Uzytkowania Lasu | Sadowski J.,Katedra Uzytkowania Lasu | Zastocki D.,Katedra Uzytkowania Lasu
Sylwan | Year: 2016

As the access to the fossil fuels is limited, renewable energy sources have been especially intensively promoted in recent years, namely biomass. A comparatively large amount of biomass can be obtained from forests. This refers to round wood characterized by low technical quality, small-sized wood, and logging residues. Under Polish conditions, the potential amount of logging residues is estimated at 3-5 Mio. m3 per year, depending on different scenarios of their ulitization. Intense development of technologies for energy acquisition from the forest biomass has provided conditions facilitating the use of logging residues on an industrial scale. One of the possible solutions is bundling. In this process slash is compacted into cylindrical log-like units with diameter of ca. 65-75 cm and length of 2.5-3.0 m. The bundles can be forwarded to the roadside landing with standard forwarders and transported to the terminal or end-user with trucks utilized, first of all, by a round wood hauling. The John Deere slash bundler 1490D was the subject of the study. The basic unit of the bundling device was an eight-wheel forwarder. The study area was located in north-eastern Poland and comprised 10 selected plots. They represent coniferous stands, dominated by Scots pine with various fraction of Norway spruce and scattered birches. The aim of the paper was to estimate the basic technological and economic parameters of the bundling machine, working in clear cuts with two variants of logging residues concentration. In the first variant they were not especially accumulated, evenly distributed over the area. In the other one they were gathered into piles. The structure of a working day, work productivity rates, and the costs were determined. The bundler productivity rate depends largely on the extent the slash is prepared. When it is concentrated in piles, the machine does not have to travel over the entire work area to gather scattered material. In this case, the average productivity was 21.85 bundles/h. In the variant with scattered logging residues, work efficiency equaled 15.19 bundles/h. The hourly-cost of the bundler use reached 289.42 PLN. The unit costs were at the level of 52.91 PLN/m3 (variant 1) and 38.54 PLN/m3 (variant 2).


Development of innovative solutions in forestry requires also that students of forestry would understand in greater extend the complex system of changes in the environment and the way the man controls these changes. It is also another challenge (innovation?) for the forest education at all levels. At the level of university education, forestry in the first half of the XXI century needs to find appropriate proposals for the methods and techniques of training, involving not only the transition from 'teaching' to 'learning'. To evaluate the level and depth of knowledge, and above all, the ability to solve problems is also the task of the future employer. These require both a corresponding adjustment of ongoing educational programs and curricula or creation of a completely new approach, which will be also accompanied by new methods of checking the effectiveness of the applied solutions.

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