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1

Zmiany w normalizacji wad drewna okrągłego w działalności Państwowego Gospodarstwa Leśnego Lasy Państwowe

100%
Wieruszewski M., Malinowski Z.
Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria
|
2018
|
tom 17
|
nr 2
2
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Nowoczesne wykorzystywanie drewna Quercus cerris (dąb burgundzki) niskiej jakości opałowej

100%
Jeno K.
Zeszyty Problemowe Postępów Nauk Rolniczych
|
1986
|
nr 296
3
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Jakość drewna topól wprowadzonych w ramach rekultywacji leśnej na zwałowisko skał towarzyszących wydobyciu węgla brunatnego

84%
Pajak M., Michalec K., Wasik R., Urban O., Vitek P., Wos B., Krzaklewski W., Pietrzykowski M.
Sylwan
|
2019
|
tom 163
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nr 10
The aim of the study was to determine quality of wood of 40−year old poplar cultivars introduced onto the external spoil dump of the Bełchatów Field and subjected to various reclamation systems. The research was carried out on the 1/78 trial plot located on the northern slope of the external spoil dump of the Bełchatów Field (central Poland). The dump was the result of the rock (predominantly sand) overlay storage accompanying lignite deposit. On the trial plot two blocks were established: one called ‘Humus’ where sandy sediments were covered with approximately 20−centimeter layer of fertile soil, and the other named ‘Piasek’ (sand) with only sandy sediments. To set up the experiment 9 poplar varieties were used (I−214, Robusta, Gerlica, H−194, Grandis, Oxford, Androscoggin, Geneva, H−275). Their wood quality was assessed in 2017, 40 years after their introduction on the spoil dump. The results indicate that poplars growing in the ‘Humus’ variant were characterised by higher volume in comparison to wood of poplars from the ‘Piasek’ variant. The latter however had a larger share of better wood quality classes (WB, WC). The results also showed that wood classification of all investigated varieties were significantly influenced by curvature in the case of the ‘Humus’ variant and knots in the ‘Piasek’ one. The influence of other wood defects such as galls, grain slope, multiple pith and knobs was insignificant. In order to obtain the higher volume of poplar raw material the reclamation treatments should be carried out on afforested areas with fertile outer layer whereas the better quality raw material can be obtained on less fertile sediments.
4

Ocena jakości wyrabianych sortymentów drzewnych w technologii maszynowej

84%
Kusiak W., Sliwinski K.
Przegląd Leśniczy
|
2015
|
tom 25
|
nr 01
5
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Zmienność rozkładu wad drewna okrągłego w dojrzałych drzewostanach sosnowych

84%
Mirski R., Wieruszewski M., Malinowski Z.
Sylwan
|
2019
|
tom 163
|
nr 11
The aim of the research was to determine the impact of selected habitat and age features on the qualitative properties of Scots pine (Pinus sylvestris L.). The research was carried out on forest stands from the Olesno, Wymiarki and Kalisz Pomorski forest districts (western Poland). The collected data provided information on technical and dimensional properties as well as quality classes for logs from Scots pine stands. The severity of the occurrence of seven basic wood defects, identified on the perimeter and length of the model log was identified and described. The collected data was used to determine the distribution of defect groups. For distributions of defect groups, normal distribution criteria were met. For the Scots pine assortments, the ANOVA showed that the hypothesis of the occurrence of an equal number of defects on the side of the logs in three separated classes of WA0, WB0 and WC0 of the quality of the raw material should be rejected. For the Tukey test, the results indicate that there is no reason to reject this hypothesis. The obtained p−value in this case is 0.09 for WB0 and WC0. There was no influence of the diameter of the logs and the habitat on the number of defects. Number of defect groups is correlated with the distance from the butt in Kalisz Pomorski and Wymiarki forest districts but not in Olesno. In that case the increase in the number of defect groups has its maximum in the zone of 6−8 m of the log length.
6
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Jakość surowca sosnowego pochodzącego z terenów rekultywowanych dla leśnictwa na przykładzie zwałowiska odpadów po wydobyciu siarki w Piasecznie

84%
Pajak K., Michalec K., Wasik R., Koscielny M.
Sylwan
|
2016
|
tom 160
|
nr 04
The research was conducted on the external spoil heap of the 'Piaseczno' Sulphur Mine (southern Poland). This paper aimed to determine the quality of wood in 40−year−old Scots pine trees planted onto the external spoil heap of the mine, in the scope of forest reclamation, depending on the soil substrate and employed reclamation treatments. The investigations were carried out at one−are circular trial plots. A total number of 17 study plots was established, located on: Quaternary loose sands (PL), mixed Quaternary sands and Tertiary Krakowieckie clays (PI), and mixed Quaternary sands and Tertiary clays after an intense initial fertilisation (PIN). Measurements performed at the study plots included determination of diameter at breast height of every tree with a diameter ≥7 cm and height of every tree. We classified the wood of standing trees, including a specification of class or quality and dimension group of the butt−end part of the trunk, identifying types and variants of defects that determined the results of quality classification of raw wood. We found significant differences in trees dimensions between soil substrates. No significant difference was found for fertilised substrates, therefore it may be assumed that fertilising of more fertile soils was an unnecessary treatment. The quality of pine wood was mostly affected by knots and curvatures. An impact of knots on the results of wood classification increased with fertility of soil substrate. With regard to curvatures, the opposite trend was recorded. The frequency of occurrence of the above−mentioned defects was determined not only by the habitat type, but also by the manner of forest management. To reduce the frequency of occurrence of the defects in question in the reclaimed areas, an appropriate closure of stands should be maintained and adequate tending treatments should be performed competently and skilfully, as this is done in commercial stands.
7

Słowniczek terminów drzewnych: Co widać na korze drzew?

83%
Kimbar R.
Drwal. Pismo Przedsiębiorców Leśnych
|
2013
|
nr 05
8

Lipa z sosną lepiej rosną

67%
Kostuch R.
Wieś i Doradztwo. Pismo Małopolskiego Stowarzyszenia Doradztwa Rolniczego
|
2015
|
nr 3
9
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Zakres wykorzystania pnia i jakość sortymentów pozyskanych harwesterem w drzewostanie sosnowym II klasy wieku

67%
Mederski P. S., Werk K., Bembenek M., Karaszewski Z., Brunka M., Naparty K.
Leśne Prace Badawcze
|
2019
|
tom 80
|
nr 1
10

Ile waży drewno? ITD już wie...

67%
Drwal. Pismo Przedsiębiorców Leśnych
|
2012
|
nr 01
11
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Klasyfikacja surowca wybranych gatunków według norm polskich i Unii Europejskiej

67%
Michalec K., Wasik K., Barszcz A., Gron A.
Sylwan
|
2016
|
tom 160
|
nr 06
The aim of this paper was to perform a comparative analysis of the quality and the value of beech, oak, fir and spruce wood classified according to the Polish and the EU standards. The research was carried out in Lesko and Baligród forest districts (south−eastern Poland). The measurements of the investigated raw wood were taken at the upper landings. With regard to fir, spruce and beech 50 specimens per species were measured, while in the case of oak only 25 pieces were examined. Each specimen was classified in respect of its quality and size according to the Polish standards (PN) and the European Union (PN−EN) standards. Then, the results of both classifications were compared in terms of the share of volumes of particular wood quality classes, the impact of wood defects on the raw wood classification results, and the value of wood determined by the means of both standards. With regard to the beech wood, the share of the poorest class D upon applying PN−EN was smaller than that for PN norms. This decrease was in favour of other classes, due to which the value of the entire beech wood increased by ca. 16%, when classified with the use of the EU standards. The oak wood revealed a slight increase in the share of wood volume in the class C and a decrease in the class D of PN−EN when compared with the Polish norms. The value of the oak wood classified with the use of the EU standards was merely by 2.3% higher than that of the Polish norms. With regard to the softwood (fir and spruce), a decrease in the share of wood of the class C in PN−EN was recorded, which was in favour of the classes B and D. The value of raw wood classified by means of the EU standards was lower for both of the coniferous species. The decrease for fir accounted for 13.3%, while for spruce it was only 1.5%. For the evaluation of the softwood, Polish classification was more profitable, whereas for hardwood the EU standards were more favourable.
12

Wysokość położenia sęków oraz lokalizacja i wielkość martwic u świerka pospolitego [Picea abies (L.) Karst.] pochodzącego z głównych ośrodków i zasięgów jego występowania w Polsce

59%
Michalec K.
Acta Agraria et Silvestria. Series Silvestris
|
2011
|
tom 49
The research presented below analyses the differences in the location of knots and injuries as well as the size of injuries on the stems of Norway spruce from different regions of Poland. The research was conducted on 32 plots located within two ranges of the occurrence of spruce in Poland: the north-eastern range and the south-western one. On the selected spruce trees, the researchers measured the height of location of knots and injuries as well as injury sizes. The analyses revealed significant differences in: the height of location of knots and overgrown injuries and the size of injuries in trees from different regions and ranges of occurrence while no such differences were found in the height of location of open injuries.
13

Nie rób dymu (1)

59%
Drwal. Pismo Przedsiębiorców Leśnych
|
2017
|
nr 11
14

Wlasciwosci drewna jodly [Abies alba Mill.] pochodzacej z drzewostanow o strukturze przerebowej

59%
Niedzielska B.
Acta Agraria et Silvestria. Series Silvestris
|
1992
|
tom 30
63-73
Tbc crops of structure depleted by partial felling creates specific conditions for growth and development of trees. The characteristic rhythm of growth of these crops, as well as morphological features of trees, especially оf their long and well developed crowns, have undoubtedly influence on wood structure and its properties. The scope of these studies was, therefore, to determine physical and mechanical wood properties of firs, grown in the crops of multifloar structure. The studies were carried out on 3 areas, established in lower mountain forest zone of Beskid Sądecki (Tab. 1), On each area 15 tentative trees were analysed. The material for studies was represented by boles taken at the level of 1.5 m of tree height. The analysed wood characteristics, of the trees from all 3 areas, do not showed essential differences. The following mean values characterize the wood: the annual ring widths 2.2 mm, the late wood part 30,8%, density 0.407 g/cm3, volumetric proportion 12.7%, compression 44,7 MPa, tension 73.3 MPa, statical bending 70,0 MPa, hardness 40.7 MPa (Tabs. 3, 4). The studies showed that the wood originating from the multifoar crops, in comparision to the wood originating from onefloar crops, is characterized by of about 13% larger annual ring width, whether density and the mechanical properties are lower of more than 10%.
15

Nie rób dymu (2)

59%
Drwal. Pismo Przedsiębiorców Leśnych
|
2017
|
nr 12
16

Charakterystyka przyrostowa oraz ksztaltowanie sie zaleznosci pomiedzy wybranymi cechami drzew a przyrostem promienia na piersnicy swierka i modrzewia

51%
Skrzyszewski J.
Acta Agraria et Silvestria. Series Silvestris
|
1995
|
tom 33
141-158
W pracy oceniono tendencję przyrostową badanych drzewostanów. Określono wpływ wybranych cech morfologicznych korony, żywotności, jakości pnia oraz masy systemu korzeniowego na wielkość 10-letniego przyrostu pola powierzchni przekroju pierśnicowego świerka i modrzewia.
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